Nutrition Flashcards
Essential vs Non-Essential Nutrients
45 essential nutrients (macro and micro nutrients) supplied by diet
Non-essential -phytochemicals, antioxidants
6 main classes of nutrients
- Carbohydrates
- Fats
- Proteins
- Water
- Vitamins
- Minerals
Macronutrients
Energy-yielding nutrients that we need in large quantities
- proteins
- carbohydrates
- fats
Why is alcohol not considered a macronutrient?
It is energy yielding but is not required by the body
Why is water considered a macronutrient?
Our body requires it in large amounts but it is not energy yielding
What are energy needs in humans based on?
Age, height, weight, and sex
ex. energy needs increase with age and peak around 18-25 years and then declines
Calculating Total Energy Expenditure (TEE) - “Energy Out”
BMR (basal metabolic rate) x PAL (physical activity levels)
What is BMR?
Basal metabolic rate - lowest amount of energy our bodies need to survive
- different for males and females
- calculated using age, height, weight, and sex (different for females and males)
How many calories per gram do carbohydrates provide?
4 kcal/g
Types of carbohydrates
- Simple Carbohydrates
- monosaccharides (gluctose, fructose, galactose) and disaccharides (maltose, sucrose, lactose) - Complex carbohydrates
- polysaccharides (glycogen - form of energy storage found in human muscle) & (starch - form of energy storage in plants) & the grain & fibre
Whole grain?
The Grain
- bran
- endosperm: starch found in endosperm only
- germ
Whole grain: endosperm + germ + bran
Refined (“white flour”): endosperm
Fibre and Types
Non-starch polysaccharide
Soluble fibre (i.e apples)
- viscous (forms gels in intestine), fermentable
- lowers GI, decreases cholesterol, feeds gut bacteria (prebiotic)
Insoluble fibre (i.e wheat bran)
- non-viscous, bulking
- relieves constipation, increases fecal bulk
Functional Fibres
- fibres added to foods
Glycemic Index
Assesses HOW a standard amount (50g) of different carbohydrate foods affect our blood glucose levels after eating them compared to a reference (50 g of glucose/white bread)
High vs Low GI
High GI - body digest sugar quickly and glucose enters bloodstream right away
- useful for athletes
Low GI - body takes longer to digest sugar and glucose is released into bloodstream over a longer period of time
- useful for individuals with diabetes
Health Canada’s “Nutrients to Limit”
Maximum 100g total sugars/day (natural + added)
W.H.O and FDA Sugar Limit
Free sugars < 10% of the total calories/day
Added sugar < 5% of the total calories/day
Maximum 50 g/day free sugar
How many calories per gram does fat provide?
9 kcal/g
Fat stored as…
triglycerides (glycerol + fatty acids)
Fatty acids
- saturated vs unsaturated (monounsaturated vs polyunsaturated)
Essential Fatty Acids
Linoleic acid (omega 6)
- LA:18:2 n-6
- plant seed oils: safflower, sunflower, corn
- associated with increased disease
Alpha-linoleic acid (omega 3)
- ALA: 18:3 n-3
- plant seed oils: canola, flax, green vegetables, walnuts
- associated with decreased blood clots, inflammation, and blood pressure
Need balance of both
6 syllables - omega 6
Non-Essential Omega 3 Fatty Acids
- Docosahexaenoic acid (DHA)
- Eicosapentaenoic acid (EPA)
- Fish oils (salmon, trout, seafood)
Health benefits:
- decreased blood clots, inflammation, blood pressure
- brain health
Two types:
Trans Fatty Acids
Unsaturated fats (trans configuration) - behave like saturated
- Naturally occuring Trans FAs (meat and milk)
- Artifical Trans FAs (partially hydrogenated oils)
Used in ultra processed foods to improve shelf life, taste & texture
Increases risk of heart disease
How many calories per gram does protein provide?
4 kcal/g
What are proteins made up of?
Polypeptides which are made up of amino acids (20)
- 9 essential and 11 non-essential
Proteins required for
- growth
- maintenance and repair of the body
- regulation of body processes (enzymes and hormones)
- fluid balance
- pH balance
Amino acid
- amino group
- carboxylic acid group
- central carbon and hydrogen atom
- side chain (“R”) - group that gives amino acids different properties
Functions of Water
- lubricant
- transport fluid
- regulates body temperature
- aqueous medium for most biochemical reactions
Micronutrients
- required in small amounts
- provide no energy but are necessary for proper functioning (regulating metabolism, cofactors/coenzymes, antioxidants)
Types of Micronutrients
Vitamins
- organic molecules
- fat soluble: Vitamin D, A, K, E
- water soluble: Vitamin C, B
Minerals
- inorganic molecules (do not contain carbon)
- 6 major minerals (Na, P, Cl, Mg, K, Ca)
Fortification
Process of artificially adding nutrients to foods because some foods naturally lack certain vitamins
ex. vitamin D in milk, B vitamins/folate in grains
Anti-nutrients
Some foods decrease absorption of nutrients
- affects bioavailability
ex. vegetables & grains
Calcium is found in milk and vegetables but it is more bioavailable from milk
Dietary Reference Intakes (DRIs) vs Canada’s Food Guide
DRIs
- Designed to prevent nutrient deficiencies
- Nutrient-based
ex. adult should have 1000mg of calcium per day
Canada’s Food Guide
- Designed to promote a balanced diet
- Food based
- Based on DRIs
Both: promote health
Estimated Average Requirement (EAR)
Average daily nutrient requirement for 50% of the population
- evidence based/scientifically derived
Recommended Dietary Allowance (RDA)
Recommended daily target intake of a nutrient to meet needs of most people (2SD > EAR)
- mathematically derived
- most accurate respresentation of what we should be eating
Adequate Intake (AI)
Estimate of what RDA should be, insufficient evidence
- nutrients required in such small amounts, assumed we are always reaching adequacy
- replacement of EAR and RDA when there’s not enough evidence to make EAR and therefore create RDA
Tolerable Upper Intake Level (UL)
Maximum daily intake of a nutrient unlikely to create adverse health effects
- increasing intake of nutrient doesn’t cause risk of excess, but at point if more than upper limit –> risk of excess
Dietary Reference Intakes (DRIs)
4 sets of values
- Estimated Average Requirement (EAR)
- Recommended Dietary Allowance (RDA)
- Adequate Intake (AI)
- Tolerable Upper Intake Level (UL)
Estimated Energy Requirement (EER)
- used to calculate total energy intake needed to maintain body weight
EER = TEE if in energy balance
Acceptable Macronutrient Distribution Range (AMDR)
- range for healthy intake as a percent of total calories
ex. carbohydrate (45 to 65%)
4 Food Groups Displayed as Rainbow
1992 - Canada’s Food Guide
- unequal portion sizes
- culturally specific items
Which years had food rules?
First Dietary Guideline for Canadians
1942 - Canada’s Official Food Rules
- rules to prevent nutritional deficiencies during war time
- organ meats and other foods as available
1944
- more indulgent (portion sizes increased, more variety of meats)
- vitamin D reccomendation
First Canadian Food Guide with Food Groups
1961 - Canada’s Food Guide
- food groups created
1977 - Canada’s Food Guide
- 4 food groups created (fruits and vegetables combined)
- eat a variety of foods from each group every day
2007-2018 Food Guide
Rainbow
- greatest portion is fruits and vegetables
- dietary references intakes: more prescriptive
- eating the recommended foods promote health and reduce risk of disease
Also discussed:
- physical activity
- food labels
- intake of unsaturated oils/fats
2019 Canada’s Food Guide
3 Food Groupings (removed milk and meat & alternatives)
- not prescriptive
- focuses on mindful eating
- water is drink of choice
- emphasis on plant based foods
Canada’s Healthy Eating Strategy
- Canada’s Food Guide
- Restrictions on Marketing to Kids
- Front-of-Pack (FOP) Labelling
- Nutrition Facts Panel & Ingredient List
Health Canada amends…
Restrictions on Marketing to Kids
Health Canada amends Food & Drug Regulations
- restricts advertising of foods to children under 13 years that contribute to excess intakes of sodium, sugars, and saturated fat
Includes;
- no use of cartoonish characters, animals, creatures, mascots, or celebrities
- cannot offer vouchers or coupons for free or discount food or beverage that meets the nutrient criteria
Applies to:
- stores, schools, restaurants, public transit, recreation centres, television and online
W.H.O
Obesogenic Environment
Environment that makes unhealthy choices the easy choices
W.H.O concerned about obesogenic environment
- expresses there is unequivocal evidence that the marketing of unhealthy foods has a negative impact on childhood obesity
Front-of-Pack Labelling
Warnings on packaged foods that indicate high saturated fat, sugar, and sodium
Exemptions to Front-of-Pack Labelling
- foods that have a recognized health-benefit
- technical (no package/nutrient facts table)
- practical (redundant foods such as honey)
Nutrients of Concern
Saturated fats, sugars, sodium
- associated with increased disease (hypertension, diabetes, heart disease, obesity)
Shortfall Nutrients
Nutrients typically under-consumed
Nutrition Labelling
- health claims
- nutrient content claims
- nutrition facts table
New vs Old Nutrition Facts Table & Ingredients List
- serving size better designed for comparison (stands out more and is more similar on similar foods)
- calories is larger and stands out more
- new % daily value for total suagrs
- new % daily value footnote
- includes shortfall nutrients (public health concern)
- new labels group all similar ingredients together to prevent decieving consumers
- greatest weight of ingredient appears first
% Daily Value
5% or less is a little (not good source of nutrient)
15% or more is a lot (good source of nutrient)
Nutrient Content Claims
- calorie free
- low in calories
- fat free/no fat
What is an organic product?
Product grown and processed using environmentally and animal friendly farming methods
Foods labelled organic are regulated by CFIA
Regulations by Canadian Food Inspection Agency (CFIA)
Only products with >95% organic content can use this logo
Multi-ingredient products with 70%-100% organic content may say “contains x% of organic ingredients” but cannot use the logo
Do organic foods still contain pesticides?
Yes
- rotenone and pyrethrin
- less harmful to food and planet but toxic to aquatic life and have been associated with cancer
Organic foods cannot…
- be genetically modified (GMO)
- be grown with synthetic pesticides
- be grown with chemical fertilizers or composted plant and animal material that contains a prohibited substance
- contain chemical/synthetic processing substances
- contain synthetic growth regulators
- be cloned animals
Are organic foods better?
There is no evidence to suggest that organic products provide health benefits that are different from conventionally produced foods
eg. milk in canada is already produced with a high standard (aritifical growth hormones are not permitted & strict measures for antibiotic use)
Pros & Cons of Gentically Modified Foods
Pros
- increased crop yield (bacteria resistant)
- help meet global food challenges
- decrease chemical use (less pesticides)
- better shelf life
- increased nutritional value
Cons
- don’t know long terms effects
Common GMO’s
- alfalfa
- canola oil
- corn
- cotton
- papaya
- milk (not in Canada, EU, Aus/NZ)
- meat is not (feed can be)
- soy
- sugar beets
- zucchini/squash
Carrots…
Selective breeding vs Genetic Engineering
Selective breeding
- modifying the characteristics of living things in order to enhance one or more desirable traits
- does not introduce foreign DNA
eg. farmers selectively bread for the mutation that concentrated carotenoids in the carrot
Genetic Engineering
- deliberate modfication of the characteristics of living organisms by manipulating its genetic material
- introduces foreign DNA
Complimentary & Alternative Medicines & Supplements include…
- ergogenic aids (sport supplements)
- amino acids (protein) and fatty acids
not drugs or food even though we ingest them
True or False: Althletes are responsible for any prohibited substance found in their biological samples
True - despite if the violation was committed unintentionally or deliberately
Sport Ergogenic Aids Examples
Beneficial Ergogenic Aids
- sodium bicarbonate
- beta-alanine
- caffeine
- creatine
- BCAAs
- protein supplementation
- sports drinks, gels, bars
- beetroot juice (nitrate)
- antioxidants
Errogenic Aids
Substances proven to improve performance/athletic capability
- evidence/studies
IOC Consensus Statement
Define Dietary Supplement
Food, food component, nutrient, or non-food compound purposefully ingested in addition to regular diet with the aim of achieving a specific health and/or performance benefit
Does nutrition contribute to successful performance?
Nutrition has a small but potentially valuable contribution to successful performance in elite athletes
Can result in…
Risk of sport supplement use
Contamination of supplements
- contaminations with hormones, stimulants, and other prohibted substances
- can result in doping infringements
