Macro nutrients Flashcards
1
Q
What are macro nutrients?
A
Macronutrients are large families of molecules that makes up the food we eat. and are required in relatively large amounts to maintain the health and funciton of the body. Macronutrients include carbohydrates, proteins, and fats.
2
Q
What are carbohydrates?
A
Carbohydrates are macronutrients made up of long chains of smaller units called saccharides, or sugars and are composed of carbon, hydrogen, and oxygen arranged into chains of sugar molecules.
Depending on their structure, they can be classified as simple or complex.
Simple carbohydrate molecules (aka simple sugars) have a basic ring structure of carbons and hydrogens.
• One ring is called a monosaccharide (mono = one).
• Two rings joined is a disaccharide (di = two).
• A few rings joined are called oligosaccharides (oligo =
few).
As carbohydrates link together in more intricate structures (hence the term “complex carbohydrates”), they become glycogen, starches, and various types of
soluble and insoluble fibers. We often call these polysaccharides (poly = many).
In order for the body to use carbohydrates they need to first be broken down into simple sugars.
3
Q
What is the difference between simple and complex carbohydrates?
A
Simple carbohydrates (simple sugars) contain one or two sugar molecules (monosaccharides and disaccharides, respectively), while complex carbohydrates are composed of a number of monosaccharide molecules (three or more) linked together
4
Q
Name two monosaccharides as well as their sources
A
Glucose: Honey, syrup, root vegetables
fructose: honey, syrup, fruit
5
Q
Name two disaccharides
A
Lactose: cow, sheep and goat’s milk,
Sucrose (common sugar): Mainly from Cane sugar and beet
6
Q
Which enzyme is required to digest lactose?
A
Lactase
7
Q
How is lactase related to lactose intolerance?
A
Lactase production declines as we age and so when people do not have enough lactase, they cannot properly digest lactase, which results in lactose intolerance
8
Q
What are oligosaccharides?
A
Oligosaccharides are comprised of three to nine monosaccharide units linked together The two main oligosaccharides are fructo-oligosaccharides (FOS) and galacto-oligosaccharides (GOS).
9
Q
What are the benefits of oligosaccharides?
A
Both fructo-oligosaccharides and galacto-oligosaccharides pass through the upper digestive system undigested and ferment when they reach the large intestine, exerting a prebiotic effect that promotes beneficial bacteria in the gut. However, this fermentation may cause flatulence and can be problematic for those with irritable bowel syndrome
10
Q
Which plants are rich in oligosaccharides?
A
fructooligosaccharides: Jerusalem artichokes, alliums (leeks, onions, and garlic), asparagus, banana, burdock root, and chicory root
Galactooligosaccharides (GOS) are found in pulses such as lentils, chickpeas, and beans
11
Q
name three different kinds of polysacharides and where each is found
A
starch: Vegetables such as corn, potatoes, beans
pectin: Mainly fruit, some vegetables, pectin in apples
used as a gelling agent
musolage: Found in demulcent herbs and plants like comfrey, slippery elm etc.
12
Q
which macro nutrient is commonly used as a thickener or gelling agent?
A
pollysacharides
13
Q
Which macro nutrient is commonly found in immuno modulating herbs?
A
pollysacharides
14
Q
Protein are broken down into …
A
Amino Acids
15
Q
Carbohydrates are broken down into…
A
Sacherides like glucose
16
Q
Fats are broken down into …
A
fatty acids
17
Q
What are the macros ratios of a balanced meal?
A
30% Protein
40 % Carbs
30% Fat
18
Q
What happens when we change the macros ratio?
A
It changes the physiological outcomes
19
Q
Why is it important to understand macros?
A
To discover the energy intake as well as the optimal ratio of protein, carbohydrate, and fat that will help you (or your clients) look, operate, perform, and recover as well as possible.
20
Q
Why is only looking at macros not suffienct when planning a diet?
A
It doesn’t tell us exactly:
- what types of macronutrient molecules are in it; nor
- the quality of that diet.
21
Q
What is an energy balance?
A
energy balance measures the amount of energy in vs the amount of energy out.
22
Q
Why should we consider the energy balance when planning meals?
A
Energy balance strongly affects our health, body composition,and performance.
23
Q
How does energy balance affect weight?
A
More in than out -weight gain
More out than in -weight loss
Same in as out -Weight stays the same
24
Q
What does the abreviation CICO stand for
A
Calories in/Caloreis out
25
What is the primary criticism of CICO?
These critics say it doesn’t account for hormone imbalances, insulin resistance, polycystic ovary syndrome (PCOS), and other health problems that affect metabolism. They often claim certain diets and foods provide a “metabolic advantage,” helping you lose weight without worrying about CICO.
26
Which variable can change body weight independend from energy balance?
water
27
What is meant by Body stores
Body stores refers to all the tissues available for breakdown, such as fat, muscle, organ, and bone
28
What is the energy balance equation?
[Energy in] – [Energy out] = Changes in body stores
29
What regulates the internal and environmental factor of energy balance?
The brain
30
What factors influence "energy in"?
Appetite : influenced by hormones that regulate hunger
and satiety
Food Consumed: influenced by Palitibillity, Energy
density, Socio-Economic status,
Education and culture
Calories absorbed: influenced by Macro nutrient intake,
age, food prep, microbiome, health
and energy status
Psycological factors: Stress, mindset, self-control, self
esteem, sleep quality
31
What factors influence "energy out"?
Energy burned at rest: influence by age, hormonal status, dieting history, genetic factors, health status, sleep
quality
Energy burned during exercise: influenced by abillity, type, frequency, duration, intensity, environment, sleep
quality and hormonal status
Energy burned by non exercise activity: influenced by occupation, leisure activities, hormonal status, health
status, energy levels, genetic factors
Energy burned by metabolizing food: influenced by macronutrient makeup and by how processed teh food
is.
32
Why is "eat less, move more" a big oversimplification?
Because it does not account for the factors, such as hormones and metabolism, that influence both intake and output
33
What are some of the problems with estimating the "exact" amount of calories in?
We don’t absorb all of the calories we consume. And
Calorie information on Food lables are not always correct and can be off by as much as 20%
Calorie information in Restuarants can be of by as much as 100 to 300%
absorption rates vary across food types. (Example: We absorb more calories than estimated from fiber-rich foods, and less calories than estimated from nuts and seeds.)
We all absorb calories uniquely based on our individual gut bacteria.
Food prep, such as Cooking, blending, or chopping food generally makes more calories available for absorption than may appear on a nutrition label.
34
what is the problem with using calory calculators to calculate calories out?
They provide an output based on averages, and can be off by as much as 20-30 percent in normal, young, healthy people. They may vary even more in older, clinical, or obese populations.
35
What are two alternative approaches to calorie counting?
hand portions and intuitive approaches
36
What are some common hormonal issues that impact energy balance and weight gain?
Menopause, Diabetes, Hypothyrodism, insulin resitance, Polycistic Ovary syndrome
37
Are results diet dependent or are they behavior dependent?
Maintaining a healthy body (including a healthy body weight) is about developing consistent, sustainable daily habits that help you positively impact “energy in” and “energy out.”
38
What is body composition?
the ratio of lean muscle vs body fat
39
What influences body composition?
Body composition is influenced by factors such as our:
• hormones (such as testosterone, estrogen, or growth
hormone);
• exercise (e.g., how often, how intensely, how long,
what type of exercise,and so on);
• age;
• medication use;
• genetic predisposition; ,
• macronutrient intake (especially protein).
40
How does energy balance affect physiological function, performance and recovery?
• Hormonal health and balance can be disrupted by
either too much or too little energy, especially over a
long period of time.
• If we don’t eat enough energy, our physical and mental
performance may decline.
• People recovering from surgery or major injuries (such
as broken bones) may need more energy than healthy
people, as energy is going to tissue repair
and rebuilding.
41
The body regulates the energy balance via the hypothalamus and a complex network of feedback loops: What happens when energy intake is consistently too low?
• If energy intake is consistently too low for a person’s needs, that person may eventually start to:
- struggle with hunger, appetite, and food cravings.
- They may also feel cold or have sluggish digestion. -----
- Their bodies are slowing metabolic rate and increasing
- the desire to eat, in order to compensate.
42
The body regulates the energy balance via the hypothalamus and a complex network of feedback loops: What happens when energy intake is consistently too high?
• If energy intake is consistently too high for a person’s needs, that person will likely store the extra energy as fat. However, depending on the person, excess energy can also be used for recovery, repair, and growth (for instance, in building muscle); or thrown off as heat.
43
What is the difference between Calories and Joules?
Calories are a measure of heat, while joules (J) are a measure of work.
44
How much energy is released by each macronutrient when burned in a lab, as measured by a bomb calorimeter?
* 1 gram of fat = 9.44 kcal
* 1 gram of starch = 4.18 kcal
* 1 gram of sucrose or glucose = 3.94 kcal
* 1 gram of protein = 5.65 kcal
* 1 gram of alcohol = 7.09 kcal
45
what are four important considerations when planning a macros diet?
weight/composition goals
physical activity
recovery
metabolic health
46
how many calories in one pound of body weight?
3500
47
What are predicitive equations?
equations that attempt to predict a client's future energy requirements?
48
What is the margin of error when predicting energy requirements?
When being very precise there is still a 5% margin of error.
49
What are the 5 main functions of protein in the body?
production and maintanance of structural proteins: colagen, elastin, kerotin, myosin, actin that maintain the strength and integrity of muscles, connective tissues (ligaments and tendons), hair, skin, and nails
Production of enzymes and hormones: All of the enzymes, which are compounds that catalyze chemical reactions in the body, are made from protein. In addition, the hormones involved in blood sugar regulation (insulin and glucagon), well as the thyroid hormones are synthesized from proteins.
Production of transport proteins: Certain proteins are used by the body to carryvarious substances to body tissues. These transport proteins include hemoglobin (carries oxygen), transferrin (carries iron), ceruloplasmin (carries copper), retinol-binding protein (carries vitamin A), albumin and transthyretin (both carry other proteins).
Lipoproteins participate in the transportation
of fat and cholesterol.
Production of immune cells and antibodies: Antibodies, such as immunoglobin IgA, IgC, IgE, which are proteins, play an important role in the immune system by attaching to antigens (viruses, bacteria, or other foreign invaders), thereby inactivating the antigens and making them more visible to the immune cells (called macrophages) that destroy antigens.
Water regulation: Maintenance of proper fluid balance: Proteins participate in the maintenance of osmotic pressure, which controls the amount of water that is found inside of cells.
50
What is protein turnover?
The ongoing process of breaking down and building
| up proteins in the body
51
What are amino acids made from?
An amino acid is so named because it has an amino, or nitrogen group (with the chemical formula NH2), on one end of its molecule, and an acidic carboxyl group (COOH) on the other. Amino acids also have what is called an “R group”, or side chain, which can
vary from amino acid to amino acid. Branched-chain amino acids (BCAAs) are so named because they have a branched side chain.
52
What is protein synthesis?
Protein synthesis is the building of new proteins. Following instructions from our DNA, proteins are built from amino acids into peptides; from peptides into
polypeptides, and from there into increasingly complicated structures, some of which can be incredibly intricate.
This complex sequence, structure and shape determines what a specific protein does, much like a puzzle piece. For instance, one type of protein might become an antibody; another might become a neurotransmitter.
53
what is protein breakdown?
the opposite of protein synthesis. Breaking proteing down to amino acids
protein -polypeptides -peptides -amino acids
54
how much nitrogen does protein contain?
16% by weight
55
How many proteinogenic amino acids are there in the human body?
20
56
where do amino acids get their names from?
From the foods they were first discovered in
57
What are the three main catagories of amino acids acording to their role?
Non-essential amino acids: We can make these amino acids in our body, so we don’t need to eat them in our diets (although, of course, we can).
Essential amino acids: We need to get these essential amino acids (aka EAAs) from food. We can’t make these ourselves.
Conditionally essential amino acids: We can make these amino acids ourselves, but not always effectively, particularly when we’re under physical stress (such as from hard athletic training, or when we’re sick). Having
extras around helps us rebuild tissues when those tissues are damaged.
58
Name the 9 essential amino acids?
```
Essential amino acids (EAAs):
Lysine
Methionine
Phenylalanine
Threonine
Tryptophan
Histidine1
```
Branched chain amino acids (BCAAs)
Isoleucine
Leucine
Valine
59
Name the 4 conditional amino acids?
Arginine
Cysteine
Glutamine
Tyrosine
60
Name the 7 non essential amino acids?
```
Alanine
Asparagine
Aspartic acid
Glutamic acid
Glycine
Proline
Serine
```
61
What are stereoisomers?
Many molecules, such as amino acids as well as sugars, exist as mirror images of each other, like right and left hands. These molecular mirror images are called stereoisomers.To differentiate between these mirror images, scientists use an L (or a minussign) or D (or a plus sign).
• L stands for laevus (left in Latin).
• D stands for dexter (right in Latin).
62
Which amino acid isomer is used for nutrition?
The L isomer.
63
What is an enzyme?
Proteins that facilitate chemical reactions (e.g.,
| breaking down molecules)
64
What is a Chiral Center?
The chemical “middle” of a mirror-image molecule;
an atom that’s bonded to four different chemical
components
65
What is deamination and why is it nescesary?
The removal of an amino group (nitrogen containing group) from an amino acid molecule in order for it to be metabolized.
66
What is the toxic byproduct of deamination?
Amonia (NH4)
67
How does the body remove amonia?
the ornithine or urea cycle, to remove ammonia by converting it into urea ((NH2)2CO). We then excrete the urea in our urine
68
What is another name for the urea cycle?
ornithine cycle
69
What is GLUCONEOGENESIS?
The process of creating glucose from noncarbohydrate sources
70
What is the difference between glucogenic and ketogenic amino acids?
glucogenic amino acids are transformed into glucose and ketogenic amino acids are transformed into ketones
71
What are ketone bodies?
Compounds made in the liver from fatty acids (and sometimes protein) when there is not enough carbohydrate for energy.
72
what are peptides?
A peptide is made of two or more amino acids bonded together
73
what is ATP?
Our body’s energy currency. Abreviation for adenosine
| triphosphate.
74
Concerning amino acids, what is meant by Primary Structure?
The sequence of amino acids in a peptide
75
Concerning amino acids, what is meant by Secondary Structure?
Formation of protein helixes or sheets from peptides
76
What are polypeptides?
Chains of amino acids longer than 25 amino acids; also
| known as proteins
77
What are antibodies?
Immune signalling protein that combats a specific
| pathogen such as a virus
78
What are neurotransmitters?
Nervous system signalling chemical
79
What is Nitrogen balance?
Ratio between nitrogen consumed and excreted;
| a measure of protein adequacy in the body
80
What is TRANSAMINATION?
Transfer of an amino group from one molecule to another, particularly from an amino acid to a keto acid
81
What is insulin?
A hormone that helps transport nutrients, particularly glucose, into cells
82
What is IGF-1?
insulin-like growth factor 1, a hormone similar to insulin that has anabolic effects and promotes growth
83
What is cell signalling?
Cells’ communication internally, or externally with other cells and their environment
84
What is translation?
The decoding of genetic information from RNA to protein
85
What is an isomer?
Molecules that have the same molecular formula, but
| different arrangements of the atoms.
86
What are stereoisomers?
Molecules that are mirror images of eachother
87
Concerning amino acids, what is meant by Tertiary Structure?
```
Three-dimensional shape of a structure built from
complex peptides (i.e. polypeptides)
```
88
Concerning amino acids, what is meant by Quartenary Structure?
Arrangement of many subunits within a large
| protein
89
What are conjucate proteins?
Proteins with non-protein parts
90
Name three different conjucate proteins?
glycoproteins (carbohydrates + protein),
| lipoproteins (fat or cholesterol + protein) and phosphoproteins (phosphate+protein).
91
What is immunoglobulin?
Antibody glycoproteins in the
| immune system such as IgA, IgG, IgE
92
What is C-reactive protein (CRP)?
A glycoprotein associated with low-level chronic
| inflammation and insulin resistance?
93
What is low density lipo protein (LDL)?
One of five major lipoprotein groups that transport
| triglycerides, fatty acids, phospholipids, and cholesterol to the body; sometimes refered to as “bad cholesterol”
94
Name 4 different kinds of glycoproteins?
Immune sytem: Immunoglobulin like IgA, IgG, IgE
C-reactive protein (CRP) is a well known glycoprotein associated with lowlevel inflammation and insulin resistance.
Hormone stimulating: Thyroid stimulating hormone (TSH), follicle stimulating hormone (FSH) and luteinizing hormone (LH) are hormones that are glycoproteins.
Cholesterol: Low-density lipoprotein (LDL) and high-density lipoprotein (HDL) are themost well-known lipoproteins that allow lipids to move around in a bodythat’s mostly water.
95
What is High density lipoprotein? (HDL)
One of five major lipoprotein groups that transports
cholesterol to the liver as a part of reverse cholesterol
transport; sometimes referred to as “good cholesterol”
96
What is Collagen?
Collagen is made up mostly of a repeating primary amino acid sequence of glycine-proline-4-hydroxyproline. This creates a special type of tightly twisted and packed helix structure, which makes collagen very strong. In fact, collagen has more tensile strength than steel wire of comparable size.
Collagen is found in connective tissue like tendons, cartilage, the non-mineral component of bone, and pretty much anywhere you need cells to stick together.
97
What can you take 1 hour before exercise to help synthesize Collagen in muscle tendons and ligaments?
Gelatine and 48mg of vitamin C
98
What improves the conversion of proline to hydroxyproline?
Vitamin C
99
Which amino acids produce creatine?
glycine and arginine
100
What is creatine?
An amino acid that is a component of phosphocreatine, a compound needed to quickly make more ATP under
intense energy demand.
101
What is creatine stored as?
Phosphocreatine
102
What is coline?
An essential nutrient involved in synthesizing and
transporting lipids, as well as methyl group metabolism
Choline is made from serine and is essential for neurotransmitters (such as acetylcholine), cell membrane components (phosphocholine), the myelin sheath, and even epigenetic modifications.
103
Describe the process by which protein is digested and absorbed
Stomach: Protein digestion really gets started in the acidic environment of the stomach.Hydrochloric acid and the enzyme pepsin (the active form of pepsinogen) begin to break down proteins. Then, the resulting
peptides and single amino acids are passed along to the small intestine.
small intestine: Once in the small intestine, enzymes from the pancreas (such as trypsin, chymotrypsin, arboxypeptidases, aminopeptidases, and collagenase) further break down proteins. Peptides must be short — fewer than 4 amino acids long — to be absorbed. The cells that line the small intestine (enterocytes) break down peptides even further, so that nearly all former proteins enter the bloodstream as single amino acids.
The liver: Most amino acids go to the liver via the portal vein. For every 100 g of amino acids taken in, about 80 g will go to the liver. Of that:
* About 20 g will be used for protein synthesis in the liver.
* About 60 g will be broken down, or catabolized, in the liver.
* About 20 g will be exported by the liver into systemic circulation.
104
What is protein denaturation?
Denaturation is the change in the threedimensional structure of the protein. Scientists sometimes call this “unfolding” of the protein, becauses key bonds that keep it folded are broken (usually hydrogen and
sulfide bonds).
protein gets denatured in the stomachs acid which has a ph of 2, so that it is easier for the pepsin to break it down.
105
Explain how the liver metabolizes and uses protein
For every 100g of amino acids consumed, 80% or 80g will go to the liver, only 20% is used for protein synthesis.
* About 20 g will be used for protein synthesis in the liver.
* About 60 g will be broken down, or catabolized, in the liver.
* About 20 g will be exported by the liver into systemic circulation.
Of the 20 g of protein synthesized in the liver:
• 14 g will remain in the liver
• 6 g will be exported to the plasma in the form of
plasma proteins (albumin, globulins, lipoproteins, etc.),
glutathione, carnitine, creatine, and other compounds.
Within the liver, proteins can be turned into enzymes
and nitrogen-containing chemicals for the liver to use.
Of the 60 g of proteins broken down in the liver:
The liver will remove the amino group (NH2) from about 60 g of protein to produce energy, glucose, ketone bodies, or fatty acids. Exactly what happens
here will depend on factors like:
• which amino acid is being broken down (e.g., some amino acids can only be used to make glucose);
• what other nutrients are available;
• how much energy is available (i.e., are we fasted or fed?); and
• what our body needs
of the 20g of Proteins exported from the liver:
Whatever the liver doesn’t use, it sends out to the plasma amino acid pool(i.e., our body’s stores of amino acids) and other cells of the body. Our body’s
cells can then extract amino acids from the plasma for various tasks, such as
synthesizing:
• muscle proteins
• skeletal and connective tissues (e.g., bones, tendons,
ligaments, cartilage)
• neurotransmitters
• enzymes
• immune system chemicals (e.g., immunoglobulins,
antibodies, cytokines)
• transport proteins (e.g., carrier proteins, lipoproteins)
Where new proteins end up depends on:
• genetic signalling;
• which amino acids are involved; and
• how much energy is available in the body.
106
What is the plasma amino acid pool?
The body’s stores of
available amino acids
circulating in blood
107
What are some of the consequences of protein deficiency?
Protein deficiency can lead to anemia,physical weakness, edema (water retention and swelling), vascular dysfunction,
and impaired immunity
108
Why do we need a constant supply of protein?
Because protein turnover is constantly occuring and because...
Proteins are crucial for nearly every aspect of cell function (as enzymes, transporters, and hormones)
and they are the major structural component of all cells in the body.
There are several essential and conditionally essential amino acids that we can’t make ourselves.
We lose some amino acids in various metabolic processes.
109
When do our protein requirements go up or increase?
• we’re training hard frequently (e.g., as athletes) or have
a heavy physical job;
• we want to gain lean mass and/or strength;
• we’re injured or sick, or are recovering from surgery;
• we’re older (because we digest protein less well, so
we need more to meet requirements);
• we’re losing protein for some other reason (e.g., chronic physical stress).
110
What are some coditions that require a lower protein intake?
* kidney disease
* certain metabolic diseases (e.g., PKU)
* liver disease
* problems with gastric emptying
* homocystinuria
111
What is PKU or PHENYLKETONURIA ?
An inherited metabolic disease that causes a
| build-up of the amino acid phenylalanine
112
What is HOMOCYSTINURIA?
An inherited metabolic disease that causes a
| buildup of homocysteine and its metabolites
113
What is the optimal protein intake for a sedentery lifestyle?
0.8 - 1.2 g/kg of bodyweight
114
What is the optimal protein intake for a person who is active but overweight or obese?
1.2 - 1.6 g/kg of bodyweight
115
What is the optimal protein intake for a person who is active with a healthy body composition?
1.6 - 2.2g/kg of bodyweight
116
What is the optimal protein intake for a person who is active with a healthy body composition who are looking to change body composition?
1.6 - 3g/kg of bodyweight
117
Why is it easier for the body to metabolize carbohydrates than protein in processes that transfer energy within our bodies.
Because Carbohydrates do not contain Nitrogen
118
Why does the body lose water when we cut out carbohydrates?
The chemical description of carbohydrates is Cn
(H2O)n or, in English, one carbon for one water, giving carbohydrates their name (carbon + hydrate, aka water).
The ratio of water to carbon has to be 1:1 for a molecule to be a carbohydrate.
Carbohydrates’ water-binding effect means that we’ll store about 3-4 grams of water per gram of stored carbohydrate in our bodies, and that
if we cut out carbohydrates, we’ll quickly lose body water (which leads to the dramatic initial weight loss on a low-carbohydrate diet)
119
Name the 5 different kinds of monosacherides
```
Glucose
Fructose
Galactose
Mannose
Ribose
```
120
Name the 4 different kinds of disacherides
Sucrose
Maltose
Lactose
Trehalose
121
Name 2 different kinds of oligosacherides
fructoligosacheride
| galactoligosacheride
122
Name 3 different classess of polysacherides
Digestible
- Starch and dextrins
- Glycogen
Partially digestible
- Inulin
- Raffinose
Indigestible
- Cellulose
- Pectin
123
Which sacheride isomer is used for nutrition or energy
The d or right isomer. Our bodies can’t metabolize L-monosaccharides
124
What is the chemical formula for monosacherides
CH2On. with n having to be equal to or more than 3, and range from 3 to 9 carbons in size. For example, both glucose and fructose, key monosaccharides in human metabolism, share the
formula C6H12O6.
125
how many units or molecules of monosacherides do monosacherides consist out of?
1
126
how many units or molecules of disacherides do monosacherides consist out of?
2
127
how many units or molecules of oligosacherides do monosacherides consist out of?
between 2 and 29
128
how many units or molecules of polysacherides do monosacherides consist out of?
between 30 and thousands
129
What are some common disacherides and what do they consist out of?
mannose: 2 glucose units
lactose: 1 glucose unit + 1 galactose unit
sucrose: 1 glucose unit + 1 fructose unit*
isomaltulose (found in honey): 1 glucose unit + 1 fructose unit*
130
What are sacherides?
Sugar molecules
131
What are monosacherides?
A single, simple sugar
132
What are disacherides?
Two simple sugars joined together
133
What are oligosachides?
A few simple sugars joined
| together
134
What is glygogen?
The storage form of a complex starch in muscle
| and liver tissue
135
What are polysacherides?
Complex carbohydrates
136
What are plysacherides used for?
energy storage: starches in plants and glycogen in humans
structure: cellulose in plants or chitin in fungi, crustaceans and insects.
mucus/joining fluid such as sanovial fluid in joints
137
what is cellulose?
A type of fiber that gives cells a rigid cell wall
138
what is chitin?
A polysaccharide that helps make up the exoskeletons of insects and crustaceans as well as the cell walls of fungi
139
What are MUCOPOLYSACCHARIDES and
| GLYCOSAMINOGLYCANS?
Polysaccharides are found
in mucus, and fluids
surrounding the joints
140
What fibers are the cell walls of plants made up out of?
The cell wall is mostly cellulose (a structural plant fiber), pectin (more fiber), hemicellulose (yet more fiber), and a little protein. Cellulose is also made up of glucose units, but it has a long, straight structure with no
coiling or branching.
141
Name two forms of starch
amylose and amylopectin
142
What is the difference between Amylose and Amylopectin
Amylose is a single helical coil — think of it as a spring.
Amylopectin has helical coils that branch off from each other, with about 20 glucose per branch. This increased branching for amylopectin means it’s easier for enzymes to get to it and break it down quickly.
143
What is fibre?
A type of carbohydrate that can’t be digested, and which
| gives plants their structure.
144
What is Pectin?
A type of soluble carbohydrate that becomes
| gelatinous (hence used in jams). Pectin cannot be digested by the body.
145
What is Hemicellulose?
A type of fiber that gives cells a rigid cell wall;
similar to cellulose but with a different chemical
composition
146
Which genes influences salivary amylase production?
AMY1, AMY2. The more copies of these genes the more amylase is produced and the better a person is able to digest carbohydrates.
147
What are the three catogories of starch according to their digestibillity?
Rapidly digesting starch Easily and quickly digested; because of this, tends to raise blood glucose quickly, and tends to have a higher glycemic index (GI) (see below)
Slow digesting starch Relatively slowly and painstakingly digested; tends not to raise blood glucose quickly; and thus tends to have a lower glycemic index (GI) (see below)
Resistant starch Difficult or impossible for humans to digest; though it can feed our gut bacteria
148
What are the different kinds of Resistant Starches?
```
RS1 is a starch that is physically
protected from digestion by being part
of a cell wall, such as in whole grains,
legumes, or seeds. Enzymes that break
down the foods can’t penetrate the
surface of the cell, which means that
only a fraction of the food’s energy and
nutrients can be accessed and absorbed.
(This is why whole nuts tend to yield
only about 70-80% of their total energy
during real-life digestion, and one reason
why minimally-processed whole foods
tend to help us lose weight.)
```
```
• RS2 has a particular type of structural
configuration, which also makes it more
difficult for digestive enzymes to access
and break down the starch. Two common
examples are green bananas and raw
potatoes. When ripened or cooked,
respectively, this starch becomes much
less resistant.
```
• RS3, or retrograded starch, occurs when
starchy foods containing amylose are
cooked and then cooled, which changes
their structural matrix to make them
more like RS2. (You’ll notice this if you cook oatmeal and then leave it in the
fridge — it becomes somewhat gelatinous
and rubbery.)
• RS4 are starches that have been
chemically modified during food
processing.
```
• RS5 are starches that are part of a larger
complex bonded to fats (like RS4, often
created during food processing), which
also makes it more difficult for enzymes
to break down the starch
```
149
How do Resistant Starches promote weight loss and healthy gut biome?
```
• less energy being absorbed overall,
compared to more bioavailable starch of
comparable volume (in other words, you
can eat the same amount of food, but get
less energy from foods high in RS);
```
• RS’s ability to absorb water and swell
up, adding bulk and volume in our
gastrointestinal tract, which in turn helps
us feel full;
```
• offering food for our gut bacteria, which
can help keep our gut microbiome
healthy and increase the production of
other beneficial substances (such as
short-chain fatty acids); and
```
• the fact that foods naturally rich in RS
are minimally-processed whole foods that
are relatively lower in calories, higher in
water, and contain a plethora of vitamins,
minerals, and phytonutrients that
promote overall health and well-being.
150
What is Glycemic index?
A measure of how quickly a carbohydrate containing
food increases blood glucose post-meal.
The GI tells us how much blood sugar goes up when we consume 50 g of usable carbohydrate from a particular food. It’s a relative measure, determined against a specific reference food — 50 g of carbohydrate from pure glucose — which is given a GI value of 100. Each food’s GI score is then calculated relative to this value of 100.
In general, the less processed and higher-fiber a food is, the more complex its carbohydrate molecules usually are. Because of this, those foods will usually take longer to digest and have a lower GI.
151
What is a resistant starch?
A type of starch with a molecular configuration that
| makes it difficult to digest
152
Explain how carbohydrates are digested?
Mouth: As soon as we take a bite of carbohydrate, salivary amylases (enzymes that break down starch) help to hydrolyze, or break down, saccharides into smaller carbohydrate chains. Salivary amylase, however, can only help with about 20% of carbohydrate breakdown, depending on how long food stays in our mouth. The less we chew, the faster we swallow, and the less salivary amylase has a chance to work on our
food. Conversely, if we eat slowly and chew well, we digest our food better with the help of these salivary enzymes. (A good reason to eat mindfully.)
Stomach: After the carbohydrate-containing food is swallowed, it travels down the esophagus to the stomach. In the stomach, carbohydrates (and all other swallowed food) get mixed into a homogenous mixture known as chyme. No further digestion of carbohydrates
happens here, as stomach acid designed to destroy potentially harmful pathogens temporarily stops the action of salivary amylase.
Small intestine: Once the carbohydrate is passed on to the small intestine, pancreatic amylases
take over, turning these smaller carbohydrate chains into disaccharides.
• The enzyme maltase breaks down maltose into two monosaccharide units
of glucose.
• The enzyme lactase breaks down lactose (milk sugar) into glucose andgalactose monosaccharides. If you lack this enzyme, the lactose in dairy will cause indigestion.
• The enzyme sucrase breaks down sucrose (table sugar) into glucose and fructose monosaccharides.
Remember, starch is made up exclusively of glucose molecules joined together into long chains. Thus, the end products of starch digestion are always glucose
monosaccharides.
All of these monosaccharide end products pass through the intestinal cells into blood vessels that take them to the liver (via the portal vein) before they enter
general circulation.
The liver: The liver takes what it needs for energy transfer and glycogen storage and then
ships the rest out as glucose monosaccharides.
You may have noticed that we can absorb galactose and fructose from our diet, but they don’t usually end up in the bloodstream. Why not?
• First, they’re both mostly converted to glucose by the liver. If there’s any
leftover glucose that the liver doesn’t think we need, it’ll turn that into
triglycerides (especially in times of caloric excess).
• Second, our liver actually prefers to use fructose rather than glucose for
energy and liver glycogen replenishment (though it can use glucose too).
Again, once the liver takes what it needs and does the appropriate chemical alchemy, the glucose units released into circulation work their way through the blood until they’re taken up into our cells.
153
How many grams of glucose do we move through the blood every hour?
20 g
154
How much glygogen can the liver store?
80 - 100g
155
How much glygogen can the muscles store?
300 - 600g
156
what does the liver do with excess glucose?
turns it into triglycerides
157
What are short chain fatty acids?
Special types of fatty acids that are shorter than 6
| carbons long, made by our gut bacteria
158
Why is Glycemic Index not the "whole story"?
Because High GI Carbs are consumed with other nutrients, such as fiber, fat and protein, all of which can alter the effect of the high GI carb on blood sugar levels.
159
What is Glycemic Load?
The glycemic load of a food is based on the glycemic index multiplied by the serving size of the food.
While this gives a better picture of how fast or significantly blood sugar may go up after a meal, GL still has some of the same problems as GI. And it too
doesn’t take into account the other elements the food may have to offer (fiber, water, phytochemicals, macronutrients, etc.).
160
What is Insulin Index?
the insulin index (II), measures the amount of insulin the body produces in response to a particular food.
161
What is the main function of Carbohydrates?
To provide energy
162
How much glucose does the brain consume?
Our brain, the most energy-greedy of all our organs, consumes about 20% of our total daily resting energy expenditure, and its preferred energy source is
glucose
163
How much glucose are required daily to meet the brains need for glucose?
The daily Recommended Dietary Allowance (RDA) for carbohydrates to meet the brain’s energy needs is about 125-130 grams (500-520 calories) per day for adults and children.
164
Where does the body get energy from in the absence of carbohydrates?
40% of that glucose would come from fat (via a component of triglycerides known as glycerol, which we’ll look at in the section on fat), and about 60% would come from gluconeogenic amino acids.
165
What is anabolic signalling?
Cellular communication that encourages nutrient
| storage, growth, and repair
166
When should we increase carbohydrate intake?
When recovering from trauma or sepsis
When we want to increase muscle mass (anabolic signaling)
When we want to increase performance
167
What is the function of fiber in our diets?
* Fiber delays stomach emptying rates, and expands in the small intestine slowing absorption. Both of these help us feel fuller, longer.
* Fiber can bind to substances such as cholesterol or hormones, helping excrete excess from the body.
* Fiber can increase gastric motility in the small and large intestine, adding bulk, absorbing water, and moving food through. Result: Good, regular poops!
• Fiber, along with resistant starches, are fermented by the microbiota in your large intestine, to make short chain fatty acids (SCFA), carbon dioxide (CO2),
CH4 (methane), H (hydrogen) and heat. SCFA are then absorbed by the large intestine, where the cells of the large intestine (colonocytes) use SCFA for energy. Having healthy, diverse, and thriving gut bacteria is closely linked to our overall health and function.
168
How much fibre do we require in our diets?
Adults up to age 50: 25 g for women and 38 g for men
Over the age of 50: 21 g for women and 30 g for men
169
What are some of the health benefits of fibre and Resistant starches?
```
increases Fecal bulk
Decreases Cholesterol and Triglyceride levels
improves gut Bacteria health
improves large intestine health through SCFA production
reduces NH3 levels
Increases Mineral absorption
Decreases Urea
Increases B vitamin synthesis
Improves Immune function
```
170
What are the estimated daily requirements of carbohydrates for normal people and athletes?
Lightly active or sedentary (e.g., regular people) 0-3.5 g/kg)
Athletes
Most strength athletes (e.g., powerlifters, weightlifters) 3.5-5.5 g/kg
Most intermittent, team-sport athletes (e.g., soccer, rugby, volleyball) 4.5-6.5 g/kg
Most endurance athletes (e.g., marathon runners) 6.5-9 g/kg
Ultra endurance athletes*(e.g., Ironman, ultramarathon)
10-12 g/kg
171
When in Ketosis, which ketones can the body use for energy?
We can use two types of ketones as energy sources, acetoacetate and D-β-hydroxybutyrate. (The β sign means “beta”.)
172
When does the body go into ketosis?
during fasting, starvation or when restricting carbs to less then 50g a day
173
How long do you have to fast for the body to go into ketosis?
approx 72 hours
174
What is ketoacidosis?
is a potentially dangerous metabolic situation of uncontrolled ketosis.
175
How does the body naturally buffer ph
If it senses acid levels rising (as happens in ketosis), it responds by buffering with more alkaline molecules (such as bicarbonate), changing blood levels of CO2, absorbing hydrogen ions, or telling the kidneys to excrete more dihydrogen phosphate and ammonium ions.
176
When the blood ph drops below _____ and our bodies are unable to regulate it we are in trouble?
7.35
177
what is the name of the process that changes fat into ketones for use as energy?
Ketogenesis.
178
Why is measuring blood ketone levels with ketosticks not a reliable indicator of wether the body is in ketosis or not?
Because it measures the amount of excess ketones excreted in the blood which is not always a reliable indicator
Ketostix also only measure the presence of excreted acetoacetate, not the presence of D-β-hydroxybutyrate
Over time, our body’s excretion of ketones can change, even if we’re still in ketosis. Therefore, you may see different readings on the Ketostix, regardless of what is actually happening in your body. .
179
When supplementing ketones, which stereo isomer should one take?
The Right stereo isomer D-β-hydroxybutyrate
180
Why is ketosis or ketones beneficial for cancer sufferers?
because most cancers have a highly anaerobic metabolism, and cannot metabolize fat which is aerobic, thus ketosis starves cancer cells.
181
Which conditions could benefit from a ketogenic diet?
Epilepsy and neurodegenerative diseases.
Cancer
Metabolic diseases: Type 2 diabetes
182
How does ketosis help metabolic disorders?
Ketones may help, in part, because they decrease oxidative stress, boost antioxidants and scavenge free radicals.
Oxidation is a natural part of cellular metabolism, but too much oxidation, too fast, without the balance of antioxidants, contributes to many metabolic and other diseases.
Many metabolic disorders are related to this process of oxidation, in which our cells essentially “rust” from the inside. If we can slow and regulate oxidation, it may improve our health and longevity.
183
What is the effect of ketosis on athletic performance?
Ketosis lets you avoid glycogen depletion (aka bonking, hitting the wall), because you aren’t using glycogen as your energy source, so you don’t need to take in carbs as you compete. Instead you’re using fat and ketone bodies. You increase fat oxidation, spare glycogen, produce less lactate and use less oxygen at submaximal rates.
All this sounds great, but the exercise physiologists’ consensus is that while all these adaptations are true, the problem is that with fat and ketone bodies as fuel, you’re not going to go as fast as you can when using with glucose and carbohydrates.
184
how do people lose weight on keto diets?
initially there is the depletion of glycogen and water loss. approx 2.5 kg
then fat and protein makes people feel fuller for longer and so the tend to eat less and therefore reduce calory intake.
There is also a small initial increase in metabolism but this is short lived.
185
Does ketosis help to build lean muscle?
NO
Ketosis reduces insulin levels
For the most part, we need insulin—along with other hormones, such as growth hormone and testosterone—to create an anabolic, muscle-building environment.
Trying to build muscle while in ketosis is like stepping on the gas and the brake at the same time.
186
Do ketosis provide an advantage in lower bodyfat over other diets?
No!
187
What are hydrocarbons?
A particular type of carbonhydrogen molecule in a
| chain structure
188
What are lipids?
A large class of water insoluble molecules
Lipids include:
• fats and oils;
• waxes;
• some vitamins (fat-soluble);
• some hormones (steroid hormones, cholestorol); and
• compound lipids (phospholipids, glycolipids, and lipoproteins).
189
What are fatty acids?
Chains of hydrogen and carbon that are the building
blocks for fats
The simplest unit of a lipid is a fatty acid.
Fatty acids are made of simple hydrocarbon chains with special chemical groups at each end:
• a methyl group (CH3) on one end (often known as the “omega” end, and
written as ω); and
• a carboxyl group (COOH) on the other (often known as the “alpha” end and
written as ɑ).
The carboxyl group is hydrophilic (or “water-loving”, i.e., can be dissolved in
water), while the methyl group is hydrophobic (or “water-fearing”, i.e., does not
dissolve in water). However, most fatty acids don’t dissolve in water, because
the methyl groups are repeated within the structure more often.
190
What are the functional/structural groupings of lipids?
1. Fatty acids
2. Triglycerides (also known as triacylglycerols),
diglycerides, and monoglycerides
3. Sterols (cholesterol, bile salts, and phytosterols)
4. Phospholipids
5. Sphingolipids
191
What are triglycerides?
Three fatty acids joined together by a glycerol
| molecule; the main storage form of fats in the body
192
What are sterols?
Lipids that have a steroid nucleus (a center with 4
| separate carbon rings) and a hydroxyl group
193
what is cholesterol?
A type of fat-based molecule found in most tissues;
| crucial in metabolism
194
what are bile salts?
A substance found in bile (produced by the
| gallbladder) that helps us digest fats
195
What are phytosterols?
Plant-based sterol compounds with potential health benefits
196
What are Sphingolipids?
```
A class of lipids with particular activity in our
nervous system
```
197
What are Phospholipids?
Lipids (diglycerides) with a phosphate group attached
198
In which ways can fatty acids vary?
```
Fatty acids can vary in:
• length (number of carbons);
• saturation of hydrogen (saturated, monounsaturated,
polyunsaturated); and
• isomerization (trans or cis).
```
199
What group is found at the alpha end of a fatty acid?
COOH -carboxyl group
200
What are the different lengths of faty acids?
Fatty acids range in size from four to about 24 carbons, most commonly 16 and 18 carbons long.
Fatty acids can be named based on length:
• Short-chain fatty acids (SCFA): Fewer than 6 carbons long (as we saw in
the section on carbohydrates, our gut bacteria can make these for us).
• Medium-chain fatty acids (MCFA): Between 6 and 12 carbons long.
Medium-chain triglycerides (MCTs) are a specific type of triglyceride (more
about those below) that have two or three MCFAs as their fatty acids.
• Long-chain fatty acids (LCFA): Between 13 to 21 carbons long.
• Very long-chain fatty acids (VLCFA): 22 or more carbons long.
201
What group is found at the omega end of a fatty acid?
CH3 -Methyl group
202
What is meant by "saturation" in regards to fatty acids?
Hydrogen bonding to a hydrocarbon chain. The more hydrogen bonded the more saturated the fat.
if all the available bonds are taken up by hydrogen it is said to be fully Saturated
if only one hydrogen atom is missing, it is said to be monounsaturated
Where more than one hydrogen atom is missing, it is said to be polyunsaturated.
203
What are saturated fatty acids?
Fatty acids with a complete set of hydrogens bonded to
the carbons and no double bonds in the hydrocarbon
skeleton
204
What are monounsaturated fatty acids?
Fatty acids without a complete set of hydrogens
| and one double bond between two carbons
205
What are polyunsaturated fatty acids?
Fatty acids without a complete set of hydrogens
| and two or more double bonds between carbons
206
Why is saturated fat solid at room temperature and unsaturated fat is not?
Because unsaturated fats tend to have a double bond where they’re missing hydrogens, there’s a “kink” or a bend in their physical shape. They can’t pack together as tightly, which means they’re usually liquid at room temperature. The less saturated the fat, the more fluid it is.
(Indeed, polyunsaturated omega-3 fatty acids act like “natural antifreeze” for cold water fish, preventing their cells from stiffening up in icy temperatures.)
Conversely, saturated fats are straight, and can pack tightly together. Given this chemical structure, saturated fats (such as butter, coconut oil, or cocoa butter)
207
What is the fatty acid makeup of an egg?
39% of the fat in eggs is saturated, while 43% comes from monounsaturated fat and 18% from polyunsaturated fat.
208
What is the difference between a cis and a trans configuration of a fatty acid?
Most naturally occurring unsaturated fatty acids have what is called a cis configuration that causes the fatty acids to bend into a U like shape around the
double bond between carbons. However, some unsaturated fatty acids can take a trans configuration, which straightens the molecule so that it looks (and acts)
more like a saturated fat.
209
What is hydrogenation?
takes an unsaturated fat (soft or liquid at room temperature) and bubbles hydrogen ions through it until it’s solid at room temperature. This is known as hydrogenation
210
What is the difference between Full and Partial hydrogenation?
Full hydrogenation makes a saturated fatty acid from a polyunsaturated fatty acid.
Partial hydrogenation makes a trans-fatty acid from a polyunsaturated fatty acid.
211
What is the main reason for industrial hydrogenation?
Polyunsaturated fats are normally reactive — they quickly oxidize and go rancid, because other things such as oxygen can bond to their hydrocarbons.
But since hydrogenated fats are polyunsaturated fats that have been artificially “filled up” with hydrogens, these fats now have a longer shelf life.
212
What are some of the effects of trans fat on the body?
This physical configuration changes how fats are
processed in our body. For instance, eating a lot of artificially produced trans fats can:
* lower HDL;
* suppress the excretion of bile acids;
* increase our own cholesterol production;
* compete with essential fats for transport into the cells;
* create and worsen essential fatty acid deficiencies
Over time, this can add up to a higher risk of many chronic diseases. Even one meal with a high trans fat content can diminish blood vessel function and elasticity
213
What is CONJUGATED LINOLEIC ACID (CLA)?
A type of naturally occurring trans-fatty acid that may
| have health benefits
214
What are essential fatty acids?
Fatty acids that are needed for healthy physiological functioning, but that can't be produced by the body.
215
What are the 5 different kinds of Omega-6 fatty acids?
Linoleic acid (LA) (18:2n-6)
Gamma linolenic acid (GLA) (18:3n-6)
Dihomo gamma linolenic acid (DGLA) (20:3n-6)
Arachidonic acid (AA) (20:4n-6)
Docosatetraenoic acid (22:4n-6)
216
What are the 5 different kinds of Omega-3 fatty acids
ɑ-Linoleic acid (ALA) (18:3n-3)
Steridonic acid (SDA) (18:4n-3)
Eicosatraenoic acid (ETE) (20:3n-3)
Eicosapentaenoic acid (EPA) (20:5n-6)
Docosahexaenoic acid (DHA) (22:6n-6)
217
What are the parent omega 3 and 6 fatty acids?
In mammals, the omega-6 fatty acid linoleic acid is considered the “parent” omega-6 because it can be converted to other omega-6 fatty acids (such as
other forms of linolenic acid, eicosatriaenoic acid, and arachidonic acid [AA]).
ALA is considered a “parent” omega-3. That’s because ALA has to be converted to eicosapentaenoic acid (EPA; 20:5 ω-3) and docosahexaenoic acid (DHA; 22: 6 ω-3).
218
How are essential fatty acids named?
Essential fatty acids are named by counting the carbons from the omega end (methyl end) to the first double bond.
219
What are the most important Omega 3 fatty acids for humans?
The most important omega-3 fatty acids for us are α-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA).
220
Which sources of Omega 3 are high in ALA?
Plant sources such as flax, chia, hemp, and walnuts are rich in ALA.
221
Which sources of Omega 3 are high in EPA and DHA?
Marine sources such as fatty cold-water fish (and fish oil) and algae (the original omega-3 sources for fish) are rich in EPA and DHA, which are widely recognized as the most beneficial omega-3 fats.
222
What is an important source of EPA and DHA for infants?
Human breast milk is also an important source of EPA and DHA for developing infants.
223
Why can't we only consume ALA?
We don’t convert ALA to EPA / DHA very well, so wherever possible, look for direct dietary sources of EPA / DHA.
224
Why are omega 3 fatty acids important for cell membrane health?
Cell membranes are fat-based. One reason omega-3 fats are soimportant is that they keep our cells’ membranes more “fluid”, which provides several benefits.
• When brain cell membranes are relatively fluid,
messages from neurochemicals such as serotonin can
be transmitted more easily.
- Getting enough EPA / DHA early in life helps with brain
development; getting it later in life helps prevent or
slow neurodegenerative disorders.
• When muscle cell membranes are more fluid, it
increases insulin sensitivity.
- These essential fats also play a role in many other
areas, including cardiovascular function, nervous
system function, and immune health.
225
What are EICOSANOIDS?
Signaling molecules that help regulate processes such as immunity or inflammation
226
How do Omega 3's and 6's influence inflamation in the body?
By regulating Eicosanoid production
Omega-3 fats are considered anti-inflammatory. They tend to promote eicosanoids that do things like:
• dilate (open up) our blood vessels to improve blood
flow;
• lower inflammation;
• prevent blood coagulation and clumping;
• decrease pain;
• dilate our airway; and
• support our immune system.
```
Omega-6s are considered pro-inflammatory. They promote eicosanoids that do the opposite of omega-3 eicosanoids, such as:
• constrict blood vessels;
• increase inflammation;
• cause blood clotting;
• increase pain; and
• constrict our airway.
```
227
What are the important omega 6 fatty acids?
linoleic acid (LA);
gamma-linolenic acid (GLA);
arachidonic acid (AA)
228
What is the omega three index?
The omega-3 index is the percent of EPA and DHA combined in the membranes of your red blood cells. This measure gives a picture of your overall omega-3 status; the fluidity of your cell membranes; and your potential risk for sudden cardiac death. For example:
• Below 4% on the omega-3 index = High risk
• Between 4-8% = Intermediate risk
• Over 8% = Low risk
229
What is Lipolysis?
The breakdown of triglycerides into fatty acids
| and glycerol
230
What are triglycerides?
Built from three fatty acids plus a glycerol backbone, triglycerides (tri = “three”) are the storage form of lipids in humans. Similarly, diglycerides (diacylglycerols)
have two fatty acids, while monoglycerides (monoacylglycerol) have one fatty
acid attached to a glycerol backbone.
231
Where in the body are triglycerides stored?
Triglycerides are stored in adipocytes (fat cells) in the body.
232
What is triglycerid synthesis?
The formation of triglycerides from fatty acids and glycerol
233
When does lipolysis occur?
during digestion and when we need to retrieved stored fat for fuel
234
What are phospholipids?
Phospholipids are lipids (diglycerides) with a phosphate group attached (PO4)
235
Why are phospholipids special?
Phospholipids are special because they are amphipathic (both hydrophilic and hydrophobic). When phospholipids are arranged with their fatty acid “tails” positioned against each other and the phosphate “heads” on the outside, it creates either a single layer micelle or a double layer (bilayer). Our cells use this phospholipid bilayer to form their membranes — semi-permeable barriers that regulate what gets in and out of the cell and the structures, known as organelles, inside it.
236
What does amphiphatic mean?
Being both hydrophilic and hydrophobic, as in the case
| of phospholipids that make up cell membranes
237
What doe Micelle mean?
Lipid molecules that arrange themselves in a spherical
| form in aqueous solutions
238
What is a phospholipid bilayer?
A double-layered formation of phospholipids that
| provides the basis for cell membranes
239
What are organelles?
Structures inside cells with particular functions
240
What are sterols?
Sterols are yet another class of lipid; they’re the most structurally different compared to the others. Sterols have a steroid nucleus (a center with 4 separate carbon rings) and a hydroxyl group.
241
What role do phytosterols play in the human body?
Plant sterols (aka phytosterols) also likely play a key role in health and function (particularly in lowering our risk of cardiovascular disease).
242
What are 3 types of sterols produced by the human body?
cholesterol;
• bile acids;
• steroid hormones (such as our sex hormones and
corticosteroids)
243
What are phytosterols?
Plant-based sterol compounds with potential health benefits; phytoestrogens are an example
244
What are steriod hormones?
A large group of sterol-based hormones, primarily our sex hormones (e.g., estrogen, testosterone) and corticoid
hormones (e.g., cortisol)
245
What is glycolosis?
A process that creates ATP from glycogen, glucose, and
| glycerol
246
What are CHYLOMICRONS?
Lipoproteins that transport fats from the small intestine
| to the liver
247
```
NON-ALCOHOLIC FATTY
LIVER DISEASE (NAFLD)
```
Aka hepatic steatosis, a buildup of fat in the liver,
usually due to a poor diet, metabolic syndrome, or
other non-alcohol-related causes
248
What is NON-ALCOHOLIC FATTY LIVER DISEASE (NAFLD)
Aka hepatic steatosis, a buildup of fat in the liver,
usually due to a poor diet, metabolic syndrome, or
other non-alcohol-related causes
249
What is LIPOPROTEIN LIPASE?
An enzyme that breaks down lipoproteins
250
What is ß-OXIDATION?
```
The oxidation (“burning”) of fat that allows for energy
release, aka fat oxidation
```
251
Where does most of the cholesterol in our body come from?
It is manufactured by the liver. Cholesterol in the food we consume does not have a significant impact on our serum cholesterol levels.
252
Why do cholesterol need lipoproteins?
because fat is not water soluble and so in order to be transported through our water based blood, it needs t be carried by lipoproteins.
253
What are the different kinds of lipoproteins that carry fat around the body?
Chylomicrons carry fats from the small intestine to the liver. They’re the largest, and contain much more triglyceride than cholesterol.
• Very low-density lipoproteins (VLDLs) are
packaged in the liver to be sent elsewhere
in the body.
• Low-density lipoproteins (LDLs) carry
what people often call “bad” cholesterol,
because they travel in the bloodstream,
carry fat to our cells, and can oxidize in
blood vessels, forming plaques that can
lead to heart disease. We need them, but
don’t want too much cholesterol in them.
• High-density lipoproteins (HDLs) are
the smallest particles, and contain the
most cholesterol relative to triglyceride.
They carry what’s often thought of as
“good cholesterol”. Generally, we want
the cholesterol in these particles to be a
little higher, as they’re like the “cholesterol
cleanup crew” that shuttles cholesterol
back to the liver for recycling.
254
What can be done to lower LDL and increase HDL?
A diet high in omega 3 and whole unprocessed food
255
What increases LDL and lowers HDL?
A diet high in saturated fats and processed foods
256
What are the 6 major roles of dietary fat?
1. It provides us with energy (indeed, it’s the most
energy-dense macronutrient).
2. It helps make and balance hormones, particularly our
steroid hormones (such as sex hormones and
corticosteroid hormones).
3. It forms our cell membranes.
4. It forms our brains and nervous systems.
5. It helps transport the fat-soluble vitamins A, D, E, and
K.
6. It gives us two fatty acids that we can’t make on our
own: a. linoleic acid (an omega-6 fatty acid), and
b. linolenic acid (an omega-3 fatty acid)
257
What are CHYLOMICRONS?
A type of lipoprotein (the largest type) that carry fats
| from the intestines to other parts of the body
258
What are VERY LOW-DENSITY LIPOPROTEINS (VLDLS)?
A large lipoprotein made in the liver that carries
| triglycerides to our cells
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What are LOW-DENSITY LIPOPROTEINS (LDLS)?
A type of lipoprotein that carries fats to our cells; can
cause plaque leading to heart disease, often called
“bad” cholesterol
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HIGH-DENSITY LIPOPROTEINS (HDLS)?
A type of lipoprotein that shuttles cholesterol back to
the liver for recycling; acts as the “cholesterol cleanup
crew”; often called “good cholesterol”
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What are fat soluble vitamins?
Vitamins (such as A, D, E,and K) that cannot dissolve
| in water, and require fat for transport and absorption
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How much fat do we need everyday?
Lightly active ~0.3-0.5 g of fat per lb of bodyweight (~0.65-1.1 g/kg)
Moderately active ~0.5-0.7 g/lb (~1.1-1.5 g/kg)
Highly active ~0.7-0.9 g/lb (~1.5-2 g/kg)
Note: Fat intake could be as low as 0.2 g/lb (0.4 g/kg) on low-fat diets, or as high as 2.0 g/lb (4.4 g/kg) for ultra-endurance athletes on ketogenic diets.
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What are the daily essential fatty acid requirements for men and woman
Omega 6: men 17g/day , woman 12g/day
| Omega 3: men 1.6g/day, woman 1.1g/day
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What are the key steps in calculating macros?
Step 1: Identify key variables in calculations.
Step 2: Estimate energy needs.
Step 3: Calculate macronutrient needs based on your
goals and activity.
Step 4: Determine your macronutrient ratio, or split.
Step 5: Choose the types of foods and meals you’ll
include.
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What are the 7 key variables that affect our energy and macros requirements?
1. Goals
2. Body weight
3. Body composition
4. Sex
5. Age
6. Activity level
7. Activity type
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How does body weight affect energy and macros requirements?
It takes energy to keep a body alive, warm, and moving around. The bigger the body, the more energy it usually needs for activity and basic functions (aka the basal metabolic rate [BMR] or resting metabolic rate [RMR]).
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How does body composition affect energy and macros requirements?
Along with body weight, how much lean or fat-free mass (FFM) we have will affect our energy needs.
• FFM such as muscle, bone, and connective tissue is metabolically active and costly to maintain. (It also requires more protein as well.)
• Having a lot of adipose (fat) tissue often lowers insulin sensitivity (i.e., our cells’ ability to respond to the hormonal signal of insulin, which is another
way of saying increases insulin resistance), which makes it harder for people’s bodies to effectively process and store carbohydrates.
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How does biological sex affect energy and macros requirements?
Biological sex, or the collection of physiological characteristics that can be divided into male and female, affects our need for energy through factors such as:
* resting metabolic rate (men’s is typically higher than women’s at the same body size)
* fat-free mass (men typically have more than women)
• hormones (testosterone, of which males have about
10-12 times more than women, increases lean mass
and metabolic rate, while estrogen and progesterone
tend to increase body fat)
• energy use and nutrient sensing (for instance, omen’s
bodies tend to defend energy balance, and resist
losing body fat, more than men’s)
These are just average tendencies, and there’s quite a lot of variation between individual males and females (for instance, a 20-year-old female Olympic wrestler will likely be much more muscular than a 60-year-old sedentary male office worker).
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What is Basal Metabolic Rate or BMR?
How much energy we use at total rest; the
| barest minimum energy required to keep us alive
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What is Resting Metabolic Rate or RMR?
Slightly higher than BMR; the energy we would use while lying down doing nothing?
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What is insulin sensitivity?
How well our cells can respond to the effects of
| the hormone insulin
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What is insulin resistance?
The inability of our cells to respond to insulin
| which results in more circulating blood glucose
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How does age affect energy and Macros requirements?
As we get older, our resting metabolic rate goes down (about 1-2% per decade after age 20), even if we’re active. This decrease is due to different factors at
different ages; for instance, ceasing to grow in your 20s, or losing lean mass
in your 50s and beyond. Age related muscle loss is known as sarcopenia. (Of course, if we’re inactive and/or eat poorly, this decline happens sooner and
faster.) Many people also do less physical exercise as they age.This means older people generally need less energy than younger ones.
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How does activity levels affect energy and macros requirements?
All movement contributes to our total daily energy expenditure (TDEE). Thiscan include:
• purposeful exercise (aka a “workout”); sport training
and/or competition
• an active job, such as construction or farming
• daily-life movement, such as housework, playing with
children, going up and down stairs, etc.
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How does activity type affect energy and macros requirements
Different activities have different levels of intensity and use different energy systems
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What is intersex?
Having biological characteristics (e.g.
chromosomes, reproductive or sexual
features, etc.) that cannot easily be divided
into typical male or female sex categories.
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What is outcomes based decision making?
Making decisions based on data and results
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What is SARCOPENIA?
A condition characterized by loss of skeletal muscle
mass and function. It is primarily a disease of the
elderly
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What is TOTAL DAILY ENERGY EXPENDITURE (TDEE)?
The total amount of energy we expend with
| metabolism plus activity
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What are Energy Systems?
Physiological processes that help us get energy
from food to power our activities; different
activities use a different mix of energy systems
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What is ATP?
Abbreviation of adenosine triphosphate; our body’s
| energy currency
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What is the electron transport chain?
A relatively slow process of energy transfer that
requires oxygen (aka aerobic) but provides a
near-limitless amount of energy
