Normal Nutrition Across the Lifespan

I.A.31,012 words5 min readCore preview

Learning objectives6

Explain the physiologic functions, digestion, absorption, and energy contribution of carbohydrate, protein, and fat.
Relate vitamins, minerals, water, and dietary fiber to body functions, food sources, deficiency risk, and excess risk.
Differentiate prebiotics, probiotics, nonnutritive sweeteners, and sugar alcohols by function, evidence, tolerance, and labeling implications.
Evaluate herbals, botanicals, and dietary supplements for indication, dose, evidence, quality, interactions, and safety.
Apply Dietary Reference Intake categories and life-stage modifiers to estimate energy and nutrient needs without treating population values as prescriptions.
Match developmentally appropriate feeding patterns, textures, and responsive feeding practices to infancy, childhood, adolescence, adulthood, and aging.

Function comes before a food list

Carbohydrate supplies glucose, supports glycogen stores, and spares some protein from oxidation. Digestible carbohydrate generally yields about 4 kcal/g. Protein supplies amino acids for structural proteins, enzymes, transporters, hormones, antibodies, and tissue turnover and also yields about 4 kcal/g. Nine indispensable amino acids must come from the diet, but protein quality depends on digestibility and the pattern relative to need, not whether a food is labeled complete. Fat supplies about 9 kcal/g, essential fatty acids, cell-membrane components, signaling molecules, insulation, and transport of fat-soluble vitamins. Digestion reduces these macronutrients to absorbable units; storage capacity and metabolic fate differ. Energy balance reflects intake relative to expenditure over time, not one nutrient in isolation.

Reference list