Nutrition Science and Public Health Nutrition
This domain tests the science of nutrient requirements and the programme logic of public health nutrition - what to recommend, to whom, and on what evidence.
Requirements and assessment
- The ICMR–NIN 2020 revision gives estimated average requirements (EAR) and RDAs built on total energy expenditure and physical activity level; the RDA is set above the EAR to cover nearly everyone.
- Fat should supply roughly 20–30% of energy, with visible fat used sparingly; protein requirements are set per kg of reference body weight.
- BMI for Asian Indians: underweight below 18.5, normal 18.5–22.9, overweight 23.0–24.9, obese 25 and above; abdominal obesity at waist ≥90 cm (men) and ≥80 cm (women).
- Anaemia is judged by haemoglobin cut-offs: below 12 g/dL in non-pregnant women, 13 g/dL in men, 11 g/dL in pregnancy.
Deficiency pictures
- Marasmus: severe wasting, no oedema, "old man" face. Kwashiorkor: oedema, low albumin, fatty liver, hair and skin changes.
- Vitamin A deficiency: night blindness, Bitot's spots; iodine: goitre, cretinism; iron: iron-deficiency anaemia; vitamin D: rickets.
Programmes
ICDS, PM POSHAN, POSHAN Abhiyaan, Anemia Mukt Bharat (the 6x6x6 strategy - six interventions, six beneficiary groups, six months), and fortified staples: iodised salt, fortified atta and rice, double-fortified salt.
Worked example
A 1.65 m woman weighs 70 kg. BMI = 70 ÷ (1.65 x 1.65) = 70 ÷ 2.7225 = 25.7. By WHO international cut-offs she is "overweight"; by Indian cut-offs she is obese. Use the Indian cut-offs and say so.
Traps
- Quoting WHO cut-offs for an Indian client.
- Treating EAR and RDA as the same number.
- Writing "protein deficiency" alone for kwashiorkor - it is protein-energy malnutrition with oedema and hypoalbuminaemia.