Why it matters, FREE from Folic Acid

This is not medical advice. If you are pregnant, trying for a baby, or a doctor has told you to take folic acid, follow that advice. The NHS advises a 400 microgram folic acid tablet before pregnancy and in the first 12 weeks, because that dose reduces the chance of neural tube defects.

Folic acid is the synthetic form

Spinach and a lemon beside a pile of yellow powder and a plain white tablet — Folate occurs in food. Folic acid is the synthetic form, used in powder and tablets.

Folate is a B vitamin found in food. Folic acid is the synthetic version, made for tablets and for adding to food, because it keeps well.

From December 2026

From 13 December 2026, non-wholemeal wheat flour in the UK must contain 250 micrograms of folic acid in every 100 grams, on top of any folate already in the wheat. That flour goes into bread, biscuits, cakes and many other daily foods. Wholemeal wheat flour is not covered. Breakfast cereals and some fat spreads have had folic acid added by choice for years.

A common gene variant

A white loaf, a darker loaf, biscuits and a bag of flour — Bread, biscuits and flour are the everyday foods the UK flour rule reaches.

A gene called MTHFR helps the body handle folate. One variant, C677T, is common. An older UK government review put two copies of it at around 5 to 10 percent of many populations. A UK study of European white men found two copies in 9.7 percent of the healthy controls. People with two copies tend to have somewhat lower folate in the blood.

The US Centers for Disease Control says people with this variant can still process folic acid, and that the variant is not a reason to avoid it. What does show up in blood tests is unmetabolised folic acid, synthetic folic acid that has not been converted. In the National Diet and Nutrition Survey it was too low to detect in almost a third of UK adults aged 19 to 64. The Scientific Advisory Committee on Nutrition says the long-term effects of that exposure are not known.

Cancer and coronary stents

A small unmarked supplement bottle next to a loaf of bread — The NHS cautions are about folic acid tablets, not about bread by itself.

The NHS medicines page says folic acid tablets or liquid may not be suitable if you have cancer, or if you have a coronary stent. The product information for 5 milligram tablets says they should not be used in malignant disease unless the anaemia is caused by a lack of folate, and that folate should not be used routinely in people who have a coronary stent.

The stent caution comes from an earlier practice of giving folate to try to stop a stent narrowing. That did not work, and it may have made narrowing more likely. Treating a diagnosed folate deficiency is a separate decision for a doctor. These cautions are about folic acid as a medicine, at doses far above the amount in a slice of bread.

How much is too much

Two bowls of corn flakes, a jug of milk and a spoon — Breakfast cereals are one of the foods already fortified by choice.

In the United States, the tolerable upper intake level for adults is 1,000 micrograms (1 milligram) of folic acid a day from fortified food and supplements. Europe uses the same 1,000 microgram figure for adults, including in a 2023 opinion from the European Food Safety Authority. That level is the highest daily amount judged unlikely to pose a risk for almost all people. It was set because a high intake of folic acid can hide the blood signs of vitamin B12 deficiency while nerve damage continues.

The UK set a guidance level of 1 milligram a day for adults, rather than a formal safe upper level. The Expert Group on Vitamins and Minerals said the evidence was not strong enough for a formal upper level, and it set no guidance level for children.

Intakes in the UK vary widely. The Scientific Advisory Committee on Nutrition found that some people, including some women who could become pregnant and some older people, have low folate, while others are already near or over 1 milligram a day. The higher intakes come mainly from foods fortified by choice, such as breakfast cereals and fat spreads, and from supplements.

Children

European upper levels for children are lower, scaled from the adult figure by body size: 200 micrograms a day at ages 1 to 3, 300 at ages 4 to 6, 400 at ages 7 to 10, 600 at ages 11 to 14, and 800 at ages 15 to 17. The United States uses similar figures for children.

An analysis of the National Diet and Nutrition Survey, published in the Journal of Nutritional Science, found that 17.2 percent of UK children aged 1 to 3 were above the folate upper level once voluntarily fortified foods were included, compared with 5.3 percent on the rest of the diet alone. Among children aged 4 to 6, 6 percent were above it once fortified foods and supplements were both counted. Less than 1 percent of the whole UK population was above the upper level from all sources. This is already the case, from foods and supplements on sale now, before flour fortification begins in December 2026.

Reading a listing

Each listing is an everyday alternative for the same kind of food, with a link to that product on the retailer's site. A product is added only after the ingredients on that page have been checked. Prices change, and the pack in the shop is the one that counts.

Sources: GOV.UK, Folic acid, bread and flour labelling, NHS, folic acid medicine, CDC, MTHFR and folic acid, Journal of Nutritional Science, UK intakes.