Vitamin B12

Of 6,192 B12 results Loop ran on urban working professionals in the latest 12-month window, 69.6% sit below 300 pg/mL — the level under which B12 stores are insufficient — and 34.5% are below 200 pg/mL, the clinical-deficiency line. The headline is essentially unchanged from the 68.2% reported in WHI 2025, on a sample now more than four times larger. National data frames the scale: community studies across India have placed B12 deficiency at roughly 47% of the adult population, rising well above that in vegetarian-majority regions (Singla et al., Indian Journal of Endocrinology and Metabolism, 2019). The Loop workforce — younger, urban, salaried, with employer-funded checkups — tests worse than the national adult average, not better.

The distribution:

The population mean of 293 pg/mL sits below the sufficiency line. This is not a long tail of a few deficient individuals dragging an otherwise healthy average down. The centre of the distribution is itself below adequate. The median worker is short.

Deficiency runs backwards through age — the 20s are the worst-off band#

Every other risk signal in this report climbs with age. Glucose dysfunction doubles between the 20s and 30s. Lipid and liver markers worsen through mid-career. B12 does the reverse. The youngest band tested is the worst — three in four professionals in their 20s are below sufficiency, and four in ten are clinically deficient — and the rate falls steadily through every subsequent decade.

The pattern is not aging biology. B12 absorption does decline with age, which would push the curve the other way. What moves it in the observed direction is behaviour: older professionals eat differently, supplement more, and have usually accumulated a few decades of medical contact that flags the deficiency at least once. The 24-year-old at a desk has none of that.

Men are markedly worse than women — at every age, in every metro#

Men test worse than women by roughly 15 points on the low threshold and 13 on outright deficiency. This is the opposite of the anemia page, where women carry the burden, and it is unusual enough to check against age — a male skew could simply reflect a younger male sample. It does not. The disadvantage holds inside every age band.

The gap is widest in the 30s — men 18 points worse on the low threshold — and never closes. By the 60s, where glucose risk has equalised between the sexes, B12 deficiency in men still runs double the female rate (30.7% versus 14.6%). The likeliest contributors are dietary rather than hormonal: women in this audience report higher supplement uptake and higher vegetarian representation, but also more consistent preventive medical contact, which is where a low B12 typically gets caught and corrected.

Bengaluru's deficiency leads the metros — but the diet story is only half-clean#

Bengaluru is the worst metro on both measures, and the gap is not marginal — its 78.8% low rate is the single finding that anchors B12 on the Bengaluru page of this report. Nearly half of Bengaluru reports are clinically deficient — 47.9%, against 23–32% everywhere else. The city's deficient-only rate is higher than three other metros' borderline-and-deficient rate combined.

The obvious explanation is diet: Bengaluru anchors a southern and Kannada food culture with heavy vegetarian representation, and B12 comes only from animal foods. The mechanism is real. The city ranking, though, does not track survey-reported vegetarianism cleanly.

By self-report, Delhi NCR (48.7%) and Pune (38.6%) have more vegetarians than Bengaluru (25.0%), yet both test better on B12. The clean "Bengaluru is vegetarian, therefore deficient" line doesn't survive the survey data. What survives is the underlying biology — the cities at the deficient end of the table are the ones where animal-product intake is lowest in practice — but self-reported diet labels are a poor proxy for actual B12 intake. A "non-vegetarian" who eats meat twice a month is closer to a vegetarian on B12 than the label suggests.

The male disadvantage compounds the Bengaluru picture. Bengaluru men test at 86.3% low and 57.0% deficient — the single worst city-and-gender cell anywhere in the dataset. More than one Bengaluru man in two is clinically B12 deficient.

Self tests worse than dependents — the reverse of every other biomarker#

On glucose, lipids, and most of the panel, the dependent layer — spouses, parents, parents-in-law on the policy — tests worse than the employee. On B12 the order flips. Employees are 12 points more likely to be below sufficiency than their dependents.

The reason is demographic. The dependent pool carries the older parent layer, and B12 deficiency falls with age. It also carries more women, who test better. The employee pool is younger and more male — precisely the two groups most exposed on this marker. The dependent-burden story that holds across the rest of the report does not hold here, and the report should say so plainly rather than force the pattern.

Supplements are widespread but haven't moved the population result#

15.0% of surveyed professionals report taking a B12 supplement — flat against 14.6% in WHI 2025 — while the biomarker rate stays at 69.6% low. Uptake is highest where the diet most demands it:

The targeting is in the right direction — vegetarians supplement more than non-vegetarians — but the level is far too low to register at population scale. Four in five vegetarians, the group that cannot meet the requirement from food, take no B12 (the Nutrition page shows how heavily this workforce leans vegetarian in the first place, and the Supplementation page shows the same uptake-versus-need gap across every micronutrient, not just this one). And supplementation, where it happens, is often the wrong tool for the job. Consumer multivitamins typically carry 2.5–25 mcg of B12; correcting an established deficiency through impaired absorption needs 500–1,000 mcg oral doses or intramuscular injection. A casual once-a-week multivitamin does not move a serum B12 of 180.

What deficiency costs before it shows on a lab#

B12 deficiency is rarely the reason a working professional ends up in hospital, so it barely surfaces in the claims data — which is the point. The cost shows up earlier and quieter, as the symptom set that gets misread as ordinary overwork.