Lipids Flashcards
tell me about dietary fats - brief overview
Have 9 calories/gram
Can give us more energy per gram but we break carbs
should be kept under 30% of your caloric intake
Only 10% of total daily calories should be from saturated fats
Oils are fats, not plant based oils so much
Butter is the main saturated fat, solid at room temperature
Keep dietary cholesterol intake under 300 mg/day
Specific type of fat, circulates in blood
what are the 4 functions of fat?
Promotes healthy skin and normal cell growth
Carries fat soluble vitamins (A,D,E,K) to where they are needed
Cushions vital organs like heart & liver
Provides a reserve of energy in the Adipose tissue: (stores fat under the skin to insulate the body)
What is the difference between fats and lipids?
Fats are part of a larger group known as lipids
Fats are a type of lipid, as are oils, lecithins, and cholesterol
Lipids are compounds of hydrogen, carbon and oxygen atoms called fatty acids.
Lipids include fats, oils, lecithin, and cholesterol
what are the classes of lipids?
Lipids are grouped into 3 main classes:
Triglycerides saturated, unsaturated (mono/poly), trans fats
Phospholipids lecithin
Sterols cholesterol, vitamin D, can be made by the body
Triglycerides - three fatty acid chains on a glycerol molecule (CHO, but not rings, are chains!)
- major type of fat in foods & the body
- 3 fatty acid chains attached to a glycerol molecule
Fatty acids: Organic compounds made up of C, H and O - most of the molecule consists of a chain of carbon and hydrogen atom
what are monounsaturated fatty acids? MUFA
Monounsaturated Fatty Acid “MUFA”
lowers LDL cholesterol (the bad cholesterol) while increasing HDL cholesterol (the good cholesterol)
Good boys, take away bad guys and bring in more good guys :)
Cholesterol circulates in our blood, raises cholesterol that takes fat away from our cells
Are liquid at room temp.
Nuts & their oils, avocado, olive oil, flax seed, canola oil, are high in “MUFAs”
what are polyunsaturated fatty acids? PUFA
Polyunsaturated Fatty Acids (PUFA) (Unsaturated - easier to break down)
Lowers LDL cholesterol. *Do not add good cholesterol or HDL
Are liquid at room temp.
Fish (eg. salmon, tuna and fish oil,)
Corn, soybean, safflowers and sunflowers and their oils (contain oils)
Omega-3 fatty acids belong to this group.
Are essential fatty acids:
roles in - brain function,
- memory,
- growth and development.
2 essential fatty acids not made by the body, must be in diet:
- linoleic acid “Omega-6”
- linolenic acid “Omega-3”
what are saturated fatty acids?
Saturated Fatty Acids
total blood cholesterol as well as LDL cholesterol (the bad cholesterol)
Solid at room temp.
Found in animal products - meat, dairy, lard (pig fat), butter, and seafood
Some tropical plant oils -such as palm oil, palm kernel oil. (Watch out for movie theatre popcorn!)
*New evidence suggests coconut oil is healthy, b/c of lauric acid
what are trans fatty acids?
Trans Fatty Acid (these are the worst, technically illegal)
unsaturated fatty acids are hydrogenated - to become trans fatty acids
Hydrogenation:
- changes the molecular structure by adding hydrogen atoms
makes the unsaturated fat (usually liquid) more solid
“keeps” longer
gives products like crackers, cookies, snacks, their crunch and, commercially baked goods etc. a longer shelf life)
BUT…
Trans fats…
-act like saturated fats
-Clog arteries,
- Raise LDL levels,
-are in the process of being banned
what are emulsifiers?
Emulsifier: a substance that allows for fat and water to mix.(which do not normally mix)
used in sauces, bread, baked goods, chocolate
Sterols - most important is cholesterol
- Have a complex chemical structure
- Eg. Cholesterol, hormones (steroids), vitamins (ex. vitamin D)
Cholesterol - no fats dissolve in water, doesn’t dissolve in blood/arteries & clogs it
- fat like substance present in all body cells
- needed for many body process, to make hormones, and bile acids
- are highest in animal organs (kidney, heart, liver)
what is cholesterol?
Cholesterol
Some cholesterol circulates in the blood in chemical packages called lipoproteins (combination of fat and protein) that help transport fats in the body (remember from the protein ppt.?)
Help proteins move in blood
The liver produces cholesterol naturally, we need small amounts of it
difference between LDL and HDL
LDL low density lipoprotein “Bad” Carries lipids in blood Takes lipids/cholesterol from liver to other tissues like muscles and fat Larger, lighter Less healthy Like a big styrofoam ball
HDL high density lipoprotein “Good”
Carries lipids in blood Carries to liver to be removed Smaller, denser More protein filled, healthier Like a small marble
Both travel through blood but do different things. We don’t need fat in our blood!!
Blood Lipid Profile of Serum cholesterol
Healthy serum cholesterol = less than 200mg/dL (dL=deciliter)
LDL = under 130mg/dL
= under 100mg/dL with heart disease or diabetes
HDL = over 40 mg/dL
Triglycerides = under 150mg/dL
Our body fat/fatty acids moving through blood
how are lipids digested and absorbed
Lipid Digestion & absorption Triglycerides reach stomach and float on top of watery contents In the small intestine, bile emulsifies the fat into droplets suspended in the liquid Pancreatic enzymes (lipases) break down fats into glycerol, fatty acids and monoglycerides These products are absorbed into the bloodstream through the villi in the small intestine to be used as energy, build structures or be stored as triglycerides
heart health
Cardiovascular disease : disease of heart & blood vessels.
Coronary heart disease: disease of arteries that lead to the heart
Atherosclerosis - (hardening/narrowing of arteries due to plaque buildup) leads to…
Hypertension - (high blood pressure) are 2 most common forms of CHD
plaque
Plaque
Cholesterol = invader and body makes plaque
Plaque buildup can lead to blood clots forming, which can cause serious health issues
Plaque breaks off and flows through arteries
This triggers the body to form a blood clot, which blocks the artery
If this occurs in arteries leading to the heart, it can cause a heart attack
If this occurs in arteries leading to the brain, it can cause a stroke
uncontrollable risk factors
Uncontrollable Risk Factors
Age - risk of heart attack increases with age (65+)
Processing cholesterol gets less effective
Gender - males are at greater risk of CHD b/c of female hormones like estrogen which protect the heart
Women have more organ cushioning
Heredity - a blood relative having CHD - genes and stuff
Race - CHD is higher among hispanic & Black populations
Genetic predispositions, socioeconomic reasons, etc.
