Food & Nutrition

The Atwater factors (physiological fuel values): Carbohydrates — 4 kcal/g. Proteins — 4 kcal/g. Fats — 9 kcal/g. Alcohol — 7 kcal/g. These are the most directly tested nutrition facts in IBPS AFO and FCI exams. Fat provides more than double the energy of carbohydrates or proteins per gram — which is why high-fat diets are calorie-dense.

Key deficiency diseases: Kwashiorkor — protein deficiency (edema, distended abdomen, skin lesions). Marasmus — protein-energy malnutrition (wasting, extreme thinness). Scurvy — Vitamin C deficiency (bleeding gums, poor wound healing). Rickets — Vitamin D deficiency (soft bones, bow legs in children). Osteomalacia — Vitamin D deficiency in adults. Night blindness — Vitamin A deficiency. Pellagra — Niacin (B3) deficiency (3 Ds: Dermatitis, Diarrhoea, Dementia). Beriberi — Thiamine (B1) deficiency. Anaemia — Iron deficiency (most common globally).

FSSAI (Food Safety and Standards Authority of India) was established under the Food Safety and Standards Act, 2006. It sets standards for food quality, safety, labeling, and additives across all food categories. Key FSSAI standards for exams: milk fat content (toned milk ≥ 3% fat, ≥ 8.5% SNF; double toned ≥ 1.5% fat; standardized milk ≥ 4.5% fat), adulteration detection standards, pesticide MRLs (Maximum Residue Limits), and food additive permitted levels.

Food preservation principles: Heat treatment — canning (>100°C kills spores), pasteurization (63°C/30min or 72°C/15sec kills pathogens). Low temperature — refrigeration (4°C slows microbial growth), freezing (–18°C halts microbial activity). Dehydration — removes water, reduces water activity below 0.6 (safe from most pathogens). Chemical preservation — salt (osmosis), sugar (osmosis), vinegar (pH < 4.0), SO₂ (antioxidant). Irradiation — gamma rays destroy DNA of pathogens without heating food.

The PDS is India's food security system — it distributes subsidized food grains through Fair Price Shops (FPS) to Below Poverty Line (BPL) and Above Poverty Line (APL) households. Commodities: wheat, rice, sugar, and kerosene. Under the National Food Security Act (NFSA) 2013, eligible households receive 5 kg of food grain per person per month at ₹2/kg (wheat) and ₹3/kg (rice). The Targeted PDS (TPDS) replaced the universal PDS in 1997.

Food fortification is the addition of micronutrients to food during processing to address widespread deficiencies. India's key programs: FSSAI has made fortification of rice, wheat flour, oil, milk, and salt voluntary with '+F' logo system. Staple programs: Salt iodization (iodine + iron — double-fortified salt), Vitamin A in milk and oil, Iron and folic acid in wheat flour (mandatory in some state programs). The PM POSHAN (Midday Meal) scheme provides fortified meals to school children.