The number that traveled around the world last week was 123 percent, and it was produced in a gerontology department in São Carlos, Brazil, by a team that never handed a single person a vitamin.

Joyce da Silva Milliati, Tiago da Silva Alexandre, and their colleagues at the Federal University of São Carlos, working with University College London, pulled the records of 5,520 people aged 50 and up out of the English Longitudinal Study of Ageing, a long-running British survey that has tracked thousands of older adults for years, and asked what happened to the ones who carried both abdominal obesity and a low blood level of vitamin D. Over roughly six years of follow-up, that pairing was associated with a 123 percent higher risk of death compared with people who had neither. The work ran on FAPESP money, the São Paulo state research foundation, not a supplement maker’s grant, and it landed in Diabetes, Obesity and Metabolism in 2026.

Take the pieces apart and the arithmetic is less tidy than “two problems, double the risk.” Abdominal obesity by itself, a waist over 102 centimeters in men or 88 in women, carried a 47 percent higher risk of death. Vitamin D deficiency by itself, a blood level under 30 nmol/L, carried up to 91 percent. The 123 percent is what you get when both sit in the same body at once, which the authors read as a feedback loop rather than simple addition.

HIGHER RISK OF DEATH IN ELSA (percent)
Belly fat alone47Low vitamin D alone91Both together123
Association only, over roughly six years of follow-up in adults aged 50 and up. No one was given a supplement. Source: Diabetes, Obesity and Metabolism, 2026

The proposed mechanism quietly undercuts the conclusion most readers will draw. Belly fat, the researchers note, “sequesters” circulating vitamin D and stores it in fat cells, pulling it out of the bloodstream where a lab test can see it. Low measured vitamin D, then, is partly a symptom of the visceral fat, not only a separate deficiency riding alongside it. That is a real physiological point, and it means the tidy instruction the number invites, top up your vitamin D and buy back some of that 123 percent, may be aimed at the wrong end of the problem.

What the press cycle skipped is that we already know what happens when you give people vitamin D in a controlled trial, because it has been done, at scale, more than once. The VITAL trial, published in the New England Journal of Medicine in 2019, randomized nearly 26,000 adults to vitamin D3 or placebo and found no reduction in cardiovascular events or invasive cancer. A meta-analysis of 80 randomized trials put all-cause mortality at an odds ratio of 0.95, with a 95 percent confidence interval of 0.93 to 0.99, about a 5 percent reduction, and cardiovascular mortality at 1.00, interval 0.92 to 1.08, which is a flat line through the middle of nothing. The observed association held. The bottle did not.

None of this is new to vitamin D. The gap between what an association survey sees and what a randomized pill delivers is the oldest confounding problem in the field, and it runs in one direction: low levels track illness, inactivity, poor diet, and, as this very study argues, body fat that hides the vitamin from the assay. Sicker, heavier, more sedentary people measure low. Give healthier people the pill and most of the projected benefit evaporates, because the pill was never the thing driving the correlation.

Someone will still profit from the round number. Vitamin D sits near the top of the supplement business, one of the biggest categories on the shelf, and it got there substantially on headlines exactly like this one, an observed link presented in a way that reads as a call to the vitamin aisle. The intervention the ELSA data actually points at, shrinking visceral fat, is the one nobody can bottle, and the one the mechanism section makes the stronger case for: lose the abdominal fat, and by the study’s own logic you stop sequestering the vitamin in the first place.

To their credit, the São Carlos team wrote this up as what it is, a risk association in an aging cohort, careful in the journal about what six years of observational data can and cannot establish. The 123 percent belongs to them. The instruction to go buy vitamin D belongs to whoever added it on the way to your feed.

Sources

  1. Diabetes, Obesity and Metabolism – Silva Milliati et al., “Does the Combination of Abdominal Obesity and Vitamin D Deficiency Increase the Risk of Death in Individuals Aged 50 or Older? Evidence From the ELSA Study” (2026)
  2. New England Journal of Medicine – Manson et al., VITAL trial of vitamin D and cardiovascular/cancer prevention (2019)
  3. Systematic review and meta-analysis of 80 randomized vitamin D trials, mortality and cardiovascular outcomes (2023)
  4. ScienceDaily – release summarizing the ELSA abdominal obesity and vitamin D mortality findings (2026)
  5. MedicalXpress – writeup with the study’s proposed sequestration mechanism (2026)