Nutrition Basics and Food Labels

Study Notes

Food consists of plants and animals consumed by organisms.
Nutrients are essential molecules for sustaining life, categorized into macronutrients (carbohydrates, proteins, lipids) and micronutrients (vitamins, minerals, water).

FDA mandates that all packaged foods have labels indicating calories and nutrients.
Food identity must display a common name or a descriptive term; ingredients are listed by abundance.
Daily values indicate the contribution of each nutrient per serving.
Serving sizes reflect typical consumption rather than recommended intake and are regulated based on Reference Amounts Customarily Consumed (RACCs).

Nutrient content claims (e.g., "low fat") and health claims (e.g., "can help lower cholesterol") are regulated.
Qualified health claims require specific disclaimers and scientific backing.
Generally Recognized as Safe (GRAS) status applies to substances deemed safe by experts, although some GRAS ingredients may be banned elsewhere due to safety concerns.
Substances like TBHQ, BHA, and shellac are commonly used food additives, with varying degrees of safety recognition by the FDA.

USDA published dietary recommendations in 1894; Recommended Daily Allowances (RDAs) were established in the 1940s.
Dietary guidelines are updated every five years by USDA and DHHS.
The Center for Nutrition Policy and Promotion (CNPP) established in 1994 provides nutritional guidance.

MyPyramid was introduced in 2005, emphasizing exercise; it has since been replaced by MyPlate.
MyPlate promotes increased vegetable and fruit intake, which together occupy half the plate, reducing grain portions.

DRIs provide nutrient reference standards for healthy individuals, covering calories, macronutrients, and micronutrients.
They aid in developing the % Daily Value and assess average health metrics by age and sex.
Macro and micronutrients are crucial for energy, growth, and enzyme functions.

Six key DRI categories include Estimated Energy Requirement (EER), Acceptable Macronutrient Distribution Ranges (AMDR), Estimated Average Requirement (EAR), Recommended Dietary Allowance (RDA), Adequate Intake (AI), and Tolerable Upper Intake Level (UL).

EER estimates average caloric needs to maintain weight based on age, sex, weight, and height.
AMDR specifies energy intake proportions from each macronutrient, calculated from an individual's EER.
Energy contributions from macronutrients are: fats provide 9 kcal/gram, while carbohydrates and proteins each provide 4 kcal/gram.

To assess energy value from food, multiply the weight of each macronutrient by its caloric value, then sum the totals.
EER calculators can help determine daily calorie needs and appropriate macronutrient distributions.