2 Essential Nutrients 45 – 50 molecules must be ingested. This includes representatives from the 4 major organic molecule groups, plus a number of inorganic substances such as including water, vitamins and minerals (Na, Fe, etc.)The USDA Food Pyramid
3 Nutrient – A substance in food used by the body for growth, maintenance, energy and repair. Carbohydrates: 55 – 60 % of daily calories. 125 – 175 g.Lipid: < 30% of daily calories. 80 – 100 g.Protein: 0.8g/kg body weight.Nucleic acids: not establishedWater: 1500 ml (average) per day.
4 Uses of nutrientsCarbohydrate: Primary energy molecule. Also found on cell membranes and as part of structure of connective tissue matrix moleculesLipid: Energy storage, plasma membrane structure, cushioning, steroid hormones.Proteins: Enzymes, receptors, hormones, structures of all kinds. Must be “complete” or “complimentary” in order to supply essential amino acids.
6 Energy Metabolism Metabolism = catabolism + anabolism Cellular respiration is a series of catabolic reactions that provide energy for the production ofThis energy is used to generate ATP from phosphorylation of ADP.It is a series of Redox reactions.ATP