Nutrition and your DNA file: what the markers actually support

What can DNA say about nutrition?

Mostly about handling rather than requirements: how efficiently you convert one form of a nutrient into another, or how well you absorb it. That is a tendency, not an amount. It can explain why a habit that works for someone else does not work for you, but it does not set a target for anything.

The honest framing is that a genotype is a starting condition and your diet, sunlight, gut and medication history all act on top of it. A marker suggesting lower vitamin D serum levels does not tell you your vitamin D level — a blood test does that, in an afternoon, for very little money.

Which nutrition markers are in a consumer DNA file?

Seven that we read: vitamin D, B12 absorption, folate metabolism, iron handling, omega-3 conversion, coeliac-associated markers and sodium sensitivity. Each rests on positions that consumer arrays cover well, and each is read against the published literature rather than a proprietary scoring system.

Evidence quality is uneven across that list, and we say which is which in the report rather than presenting seven readings as though they were equally solid.

Should I change my diet or take supplements based on a DNA report?

Not on the report alone. Where a marker suggests you might absorb or convert something poorly, the useful next step is measurement — a blood test that tells you your actual level — followed by a conversation about whether anything needs changing. A genotype suggests where to look; it does not tell you what you will find.

Supplements are not harmless by default, and some of them interact with prescriptions. Nothing here is a diagnosis, and none of it replaces a conversation with a clinician who knows your history.

Check your DNA