Folic acid: should it be added to our flour?

Folic acid has jumped into the public consciousness following the controversial decision to introduce folic acid fortification of non-wholemeal wheat flour in the UK from December 2026.

Presented as a public health measure, this has raised concerns and questions about whether adding synthetic vitamins to everyday foods is necessary and whether there will be health issues as a result.

What is folic acid?

Folic acid, also known as B9, is a water-soluble vitamin essential for human health. The naturally occurring form is known as folate. Folic acid is its manufactured, stable form, used in supplements and fortified foods.

Vitamin B9 plays several important roles in the body:

Red blood cell production

Helps produce and maintain healthy red blood cells, playing a vital role in the transport of oxygen and the prevention of anaemia. Anaemia can lead to fatigue, shortness of breath and weakness.

DNA and nervous system function

Supports DNA production and cell division and contributes to normal brain and nervous system function.

Healthy development during pregnancy

Folate is essential for the early development of an unborn baby's brain and spinal cord. A deficiency during the early stages of pregnancy can increase the risk of neural tube defects, including spina bifida.

Individuals who are hoping to get pregnant or in the first 12 weeks of pregnancy are advised to take a folic acid supplement. Ask a health practitioner for advice on the dose.

Folate deficiency anaemia 

Folic acid is also prescribed to treat folate deficiency anaemia and may be recommended for people who have difficulty absorbing sufficient folate from their diet.

Folate deficiency anaemia can be caused by several factors, including coeliac disease, blood loss (including repeated heavy periods), gastrectomy, inflammatory bowel disease (IBD) and medications such as methotrexate.

Where is folate/B9 naturally found?

Folate/B9 occurs naturally in a wide variety of everyday foods which are easily accessible:

• Dark leafy green vegetables: Spinach, kale, cabbage, spring greens and broccoli.
• Legumes: Lentils, chickpeas, kidney beans, peas and other pulses.
• Vegetables: Brussels sprouts, asparagus, beetroot and cauliflower.
• Fruit: Oranges, avocados and other citrus fruits.
• Nuts and seeds: hazelnuts, walnuts, flaxseeds, chestnuts, pistachios, almonds and sunflower seeds.
• Animal products: Salmon, eggs, beef, lamb. Liver is particularly rich in folate, although pregnant women should avoid eating liver because of its high vitamin A content.

Why is folic acid being added to flour?

The UK government has introduced a requirement to add folic acid to non-wholemeal wheat flour from 13 December 2026. Their goal is to reduce the number of babies born with neural tube defects, including spina bifida. The government estimates that the measure could prevent approximately 200 cases annually.

The reasoning seems straightforward and in the public interest: flour is widely consumed, so adding folic acid increases the amount available to the general population, including women who may become pregnant without planning to do so. However, it raises questions about whether a population-wide approach is preferable to greater education and support around pre-conception and early pregnancy, where the risks are greatest. 

Education could help raise awareness of the importance of folic acid supplementation before and during early pregnancy, helping to reduce the risk of potential deficiencies.

Potential health concerns

Folic acid is water-soluble, meaning that unused amounts can be eliminated through urine. However, the body's ability to process synthetic folic acid is not unlimited. When intake exceeds its processing capacity, some unmetabolised folic acid can remain circulating in the bloodstream.

Scientists have investigated whether this could have adverse health consequences. However, it is important to acknowledge that the presence of unmetabolised folic acid in the blood has not, by itself, been shown to cause disease, and no confirmed health risks have been established at recommended fortification levels.

Is adding folic acid to flour necessary?

As explained earlier, people can obtain vitamin B9 naturally through a balanced diet, and eating folate-rich foods is an excellent way to support health. However, natural dietary folate alone cannot be relied upon to provide sufficient protection against neural tube defects during early pregnancy.

Fortification is intended to provide additional protection at population level, rather than replace healthy eating or individual supplementation. Monitoring the effects of fortification on the overall population will be difficult and potentially costly.

In the UK, the new requirement applies to non-wholemeal wheat flour, rather than wholemeal flour, allowing consumers to choose alternatives if they wish to avoid fortified flour.

Ultimately, folic acid is an essential nutrient. It is important that individuals are encouraged to eat a varied diet rich in naturally occurring folate, and educated about supplementation and its effects.

If you have any concerns or are unsure about supplementation, please contact a health professional for guidance and advice.