Science1 publisher2 min readPublished
Framingham MRI study ties each 3-point MIND diet gain to 2.5 years of slower brain aging
Researchers following 1,647 Framingham adults linked each 3-point rise in MIND diet score to slower grey matter loss, equal to about 2.5 years of brain aging. The cohort is observational, so the result shows how eating habits tracked with brain shrinkage and cannot say how much of the difference the food itself caused.
The Scientist · Science desk
What happened
- Participants came from the Framingham Heart Study Offspring cohort and were 60 years old on average when the study began.
- Ventricles, the fluid spaces that widen as tissue shrinks, enlarged 0.071 cubic centimetres a year more slowly per step, about one year of delayed aging.
- Berries tracked with slower ventricular enlargement, and poultry with both slower ventricular enlargement and slower grey matter decline.
Compiled by The ScientistSomething wrong?How this is made
Why it matters
- contradiction The release summary calls the 2.5 years its 'strongest differences', but the results tie that figure to each 3-point step, so it is not a comparison of the most and least adherent eaters.
- constraint If the 2.5 years is the 20% slowing summed over 12 years, it belongs to this follow-up window, and a longer study at the same rate would report a bigger number.
- constraint Because the outcomes are MRI volumes, any claim about memory or Alzheimer's risk rests on brain structure standing in for those outcomes.
The 2.5 years is a rate converted into time, and the release's own numbers point to how the conversion works. Multiplying the researchers' 20% slower decline [8] by the average 12-year follow-up [7] gives 2.4 years [1]. Ventricular volume behaves the same way: 8% of 12 years is just under one year, against the roughly one year reported [2]. The 0.279 cubic centimetre figure also implies that typical age-related grey matter loss in this cohort ran at about 1.4 cubic centimetres a year [3].
A 3-point step is a fifth of the 15-point scale. With the average score just under 7 [5], it is roughly the gap between a typical participant and one scoring 10 [4]. The diet behind the score emphasises leafy greens and other vegetables, berries, nuts, whole grains, fish, beans, olive oil and poultry, with moderate wine. It limits butter or margarine, cheese, red meat, pastries and sweets, and fried fast food [13].
The study, published online in the Journal of Neurology Neurosurgery & Psychiatry [1], is strongest on the brain side. Each participant had at least two MRI scans between 1999 and 2019 and no stroke or dementia at the first [4], so the outcome is how fast each person's own brain changed. Diet is the softer measurement. It came from food frequency questionnaires completed at check-ups between 1991 and 2001, at least one per person [3]. For some participants, a single questionnaire from the 1990s is the dietary record set against scans that ran to 2019 [3][4].
The most adherent eaters were different people before anyone scanned them. The highest third were more likely to be women and college educated, and less likely to smoke or to have obesity, type 2 diabetes, high blood pressure or cardiovascular disease [6]. The release describes those three conditions as ones that can affect brain health [6]. It does not say how the analysis adjusted for any of these differences.
Each food is its own comparison, so I'd treat the single-food results as leads for a trial to test. The release's summary groups fried fast foods with sweets as linked to greater tissue loss [12]. The detailed findings it reports are for sweets: higher intake went with faster ventricular enlargement and greater hippocampal atrophy [11].
What to watch
- Whether the full paper's models adjust for education, smoking, obesity, diabetes and blood pressure, and how far the 0.279 cubic centimetre estimate moves when they do.
- Effect sizes and confidence intervals for individual foods in the published paper, especially fried fast food, which the release summary names but its detailed results do not quantify.
- Any analysis in this cohort linking the slower grey matter loss to memory test scores or dementia diagnoses.