Essential Nutrients
a chemical, required for metabolism, cannot be synthesized or cannot be synthesized rapidly enough
Nutrient is essential if…
- removing nutrient causes deficiency and deline in health
- puttong nutrient back into diet corrects problem and health returns
deficiency
prevention of disease
nutritional requirement
ensure optimal health
daily values
based on 2,000 Calorie a day diet, made using Dietary Reference Intakes (DRIs)
Dietary Reference Intake (DRI)
umbrella term, set of reference values for nutrients, scienctific basis for developing food guidelines
1. Estimated Average Requirement (EAR)
2. Recommended Daily Allowance (RDA)
3. Adequate Intake (AI)
4. Tolerable Upper Limit (UL)
Estimated Average Requirement (EAR)
the needs of 50% of population are met
Recommended Dietary Allowance (RDA)
needs of ~97.5% of population are met, RDA = EAR + 2 * STD DEV
Tolerable Upper Limit (UL)
the highest level of continuous daily nutrient intake that causes no risk of adverse effects
excess nutrients, above UL, increased risk of adverse effects = don’t go above UL
Adequate Intake (AI)
when sufficient evidence is not available to establish EAR and RDA, expected to meet or exceed the needs of most
Nutrient Class: Organic
Macronutrients: carbohydrates (and fibre), lipid, protein
Micronutrients: vitamins
Nutrient Class: Inorganic
Micronutrients: Minerals
Water
Water
essential nutrient, needed for many biological processes
Water Toxicity
Water Intake»_space;> kidney’s ability to process (too much water), leads to hyponatremia
Hyponatremia
hypo = low, natremia = sodium
water/sodium imbalance
can occur from excessive food intake and/or under-replacement of sodium
typically avoided with urination
causes CNS edema (cells swell + burst) and muscle weakness
