UPPSC 2019 Prelims GS Paper-I · Question 92 of 150

Correct — A, Iron. Human breast milk is close to a complete food for the first six months: it supplies proteins (whey-dominant lactalbumin plus casein), lactose, fats with essential fatty acids, all the major minerals in a form an infant's kidneys can handle, and a package of protective factors — secretory IgA, lactoferrin, lysozyme and live cells — that no substitute reproduces. The one mineral it is conspicuously poor in is iron. A healthy full-term baby manages anyway for two reasons: it is born with a store of iron laid down in the liver during the last trimester of pregnancy, and the small amount of iron in breast milk is bound to lactoferrin and absorbed far more efficiently than the iron in cow's milk or in formula. Those stores are, however, finite — they run low at roughly four to six months, which is exactly why complementary feeding starts at six months and why India's infant nutrition programmes push iron supplementation for young children. Calcium, magnesium and potassium are all present in adequate, well-absorbed amounts, so iron is the only defensible answer.

• (b)Calcium — Breast milk supplies calcium in a highly bioavailable form, and the rapid bone growth of the first months runs on it. Its calcium concentration is lower than cow's milk, but the fraction actually absorbed is much higher — low concentration is not the same as deficiency, and calcium deficiency is not a recognised problem in exclusively breastfed term infants.
• (c)Magnesium — Magnesium is present in adequate quantity; dietary magnesium deficiency in an exclusively breastfed, healthy term infant is not a described clinical problem. Candidates pick it only because magnesium is the least familiar mineral on the list.
• (d)Potassium — Breast milk is a good potassium source — its potassium clearly exceeds its sodium, an electrolyte balance suited to the immature infant kidney. Nothing about breastfeeding creates a potassium gap.

Breast milk changes as lactation proceeds: colostrum in the first few days is thick, yellow and loaded with immunoglobulins and other immune factors; it gives way to transitional and then mature milk, which is higher in fat and lactose. Mature milk delivers energy, protein, fat, lactose, calcium, magnesium, potassium, sodium and most vitamins in proportions tuned to the infant. The recognised gaps are iron (and, in most populations, vitamin D). WHO and the Government of India therefore advise exclusive breastfeeding for the first six months, followed by nutritionally adequate complementary feeding with breastfeeding continued up to two years or beyond.

The question hands you the reasoning in its own wording — 'almost complete... but it lacks'. So the task is to name the one classic gap. Three options are minerals that breast milk supplies without difficulty; only iron is the mineral around which an entire public-health apparatus has been built for infants, from delayed cord clamping and iron-folic-acid syrups to the six-month complementary-feeding rule. The trap is the intuition that milk means calcium: it is true that breast milk holds less calcium than cow's milk, but the absorbed amount is sufficient, whereas the iron shortfall is real and is why infants become anaemic in the second half of the first year if complementary feeding is delayed.

• WHO and the Government of India advise exclusive breastfeeding for the first six months, then complementary feeding with continued breastfeeding up to two years or beyond.
• Breast milk is low in iron; a full-term newborn draws on iron stores built in the third trimester, and those stores are largely spent by about four to six months.
• The iron that is present is bound to lactoferrin and absorbed far better than the iron in cow's milk or in unfortified formula — which is why exclusive breastfeeding still works for the first half-year.
• Vitamin D is the other classic gap in breast milk, and vitamin K is so low that a prophylactic vitamin K dose at birth is standard practice.
• Colostrum, the first milk of the initial few days, is rich in secretory IgA and other immune factors — the reason it must not be discarded, though many communities traditionally do.

• Reading 'almost complete diet' as complete forever — it is complete for roughly the first six months only, after which complementary food is essential.
• Assuming milk automatically means calcium and choosing (b); the calcium is adequate, it is the iron that is short.
• Believing cow's milk solves the problem — cow's milk is also low in iron and its iron is absorbed far worse than breast-milk iron; early cow's milk feeding worsens infant iron status.

UPPSC likes one-line nutrition facts of exactly this shape — a food source paired with the single nutrient it lacks, or a nutrient paired with its deficiency disease. Learn the gaps (iron, vitamin D, vitamin K in breast milk; vitamin C in cow's milk; lysine in cereals) rather than long composition tables.

• practice — not a real PYQ

  For how long does the World Health Organization recommend exclusive breastfeeding of an infant?

  • (a)The first 3 months
  • (b)The first 6 months
  • (c)The first 9 months
  • (d)The first 12 months

  Answer(b) The first 6 months — after which complementary feeding begins while breastfeeding continues up to two years or beyond.

• practice — not a real PYQ

  Colostrum, the milk secreted in the first few days after childbirth, is especially valuable to the newborn chiefly because it is rich in

  • (a)Iron
  • (b)Immunoglobulins and other protective factors
  • (c)Vitamin D
  • (d)Dietary fibre

  Answer(b) Immunoglobulins and other protective factors — colostrum is dense in secretory IgA, lactoferrin and lysozyme, giving the newborn passive immunity.