This topic will cover the fundamentals of nutrition including macronutrients (carbohydrates, proteins, fats), micronutrients (vitamins, minerals), water, and their roles in the body.
Basics of Nutrition – Quick‑Reference Notes
| Category | Primary Functions | Key Sources | Recommended Daily Intake* |
|---|---|---|---|
| Carbohydrates | • Main energy source (4 kcal/g) • Spare protein for tissue repair • Provide fiber for gut health |
Grains, fruits, vegetables, legumes, dairy, sugars | 45‑65 % of total calories |
| Proteins | • Build/repair muscles, enzymes, hormones (4 kcal/g) • Provide amino acids for cell functions |
Meat, fish, eggs, dairy, legumes, nuts, soy | 10‑35 % of total calories (0.8 g/kg body weight for adults) |
| Fats | • Concentrated energy (9 kcal/g) • Essential fatty acids (omega‑3, omega‑6) • Fat‑soluble vitamin absorption |
Oils, butter, nuts, seeds, fatty fish, avocado | 20‑35 % of total calories (focus on unsaturated fats) |
| Vitamins | • Co‑enzymes & regulators of metabolism • Antioxidant protection |
Fruits, vegetables, dairy, fortified foods | Varies by vitamin (e.g., Vitamin C 75‑90 mg, Vitamin D 600‑800 IU) |
| Minerals | • Structural (Ca, P) • Electrolyte balance (Na, K, Cl) • Enzyme cofactors (Fe, Zn) |
Dairy, meat, whole grains, nuts, leafy greens | Varies by mineral (e.g., Calcium 1000 mg, Iron 8‑18 mg) |
| Water | • Solvent for biochemical reactions • Temperature regulation • Transport of nutrients & waste |
Water, soups, fruits, vegetables | ≈2.7 L (women) / 3.7 L (men) total water intake |
*Percentages refer to total daily caloric intake; absolute gram/ milligram values depend on age, sex, activity level, and health status.