Food, Nutrition and Dietetics: Nutrients, Balanced Diets and Diet Planning
This domain tests nutrient functions, food sources, deficiency diseases, food groups, balanced diets, recommended allowances, and simple diet calculations. UPMSP expects exact terminology and the ability to modify a diet for age, activity, pregnancy, or disease.
Core rules
- Energy yields: carbohydrate 4 kcal/g, protein 4 kcal/g, fat 9 kcal/g. Alcohol yields 7 kcal/g but is not a nutrient.
- Macronutrients (carbohydrate, protein, fat) are needed in grams; micronutrients (vitamins, minerals) in milligrams or micrograms.
- Proteins supply essential amino acids. Cereal proteins are limited in lysine, pulse proteins in methionine; combining cereal and pulse improves protein quality.
- ICMR-NIN 2020 gives an adult protein RDA of 0.83 g/kg/day; energy depends on age, sex, body weight and physical activity level.
- Food groups: cereals and millets; pulses and legumes; milk and flesh foods; fruits and vegetables; fats and oils; sugars. A balanced diet includes all groups in proportion, plus fibre and safe water.
- Deficiency signs: vitamin A-night blindness, xerophthalmia; vitamin D-rickets, osteomalacia; iron-microcytic anaemia; iodine-goitre, cretinism; thiamine-beriberi; niacin-pellagra (diarrhoea, dermatitis, dementia); vitamin C-scurvy.
Worked example
Plan a 2,000 kcal diet with 15% energy from protein and 30% from fat. Protein = 0.15 × 2,000 ÷ 4 = 75 g. Fat = 0.30 × 2,000 ÷ 9 = 66.7 g. Carbohydrate supplies 55% = 1,100 kcal ÷ 4 = 275 g. Check: 300 + 600 + 1,100 = 2,000 kcal. Reasoning: 75 g protein is not 75 g of pulse; pulses are roughly 20–25% protein, so cereals, pulses, milk and a small amount of flesh food must be combined to reach the target.
Traps
Confusing percentage of energy with grams; treating RDA as a minimum for everyone; ignoring that vitamin C enhances non-heme iron absorption while phytates, tea and excess calcium inhibit it; assuming more protein is always better; forgetting that prolonged boiling destroys water-soluble vitamins.
Exam focus
Calculations, deficiency matching, balanced-diet justification and therapeutic modifications.