What is fortification?

It’s when vitamins and/or minerals are added to foods in order to enhance or “fortify” the flour and give it heightened nutritional and health benefits.

So what is flour fortification in the UK?

Currently, in theory, all milled white and brown non-wholemeal wheat flour manufactured and sold in the UK has calcium, iron, thiamine and niacin added. This practice began in post-WW2 Britain when deficiencies in the diet - due to rationing and shortages - gave support to the idea of fortifying wheat flour as a useful way to strengthen the diet of the nation. According to the Association of UK Dieticians, the "addition of calcium was required from 1941 [and] the addition of iron and niacin and thiamine was required from 1956". Following this, The Bread and Flour Regulations 1998 and The Bread and Flour Regulations (Northern Ireland) 1998 were enacted to "protect against nutrient deficiencies within the UK population".

But surely this doesn't apply to small artisan windmills and watermills?

Good point, the equipment and capital needed for small mills to comply with the regulations would likely force most very mills small to close. The association that represents the UK's large milling interests, UK Flour Millers argue that exception of "small mills from fortification requirements...[goes] against the spirit of the Regulations, which, ultimately, enforces a public health policy.". We have a number of unfortified flours, should you be looking to avoid fortified ones.

Why is it an issue now?

Though the consultation document is still going through discussion, it is expected that all milled white and brown non-wholemeal wheat flour imported into the UK must be fortified now that the UK has left the EU (Brexit). According to the UK Gov website “The EU asked whether UK objectives in terms of public diet could be addressed in what would be, in their view, a less trade restrictive manner than a total ban on imports for non-enriched flour” and the answer appears to be…no, citing the UK’s existing World Trade Organisation and “Most Favoured Nation” commitments.

So is this good for my diet and health?

There isn't any strong evidence that it is bad for health, or injurious. Regarding niacin intake, the U.S. activist group Environmental Working Group points out that a combination of fortified flour, breakfast cereals and other fortified foods could raise a child's daily intake above the recommended maximum; while the highly respected Mayo Clinic lists drug interactions and side-effects due to excessive niacin consumption (though all well beyond the expected intake from simply consuming fortified flour, and the clinic regard niacin as generally safe).

There's also not strong evidence that, in today's British consumers diet, the continuation of the post-WW2 fortification of flour with calcium, iron, thiamine and niacin is of significant benefit to consumers (according to UK Gov's Scientific Advisory Committee on Nutrition (SACN) 2012 report on Nutritional Implications Of Repealing The UK Bread And Flour Regulations). And concurrently with the flour fortification there are still claims of micronutrient shortfalls* in the UK population due to varied diets [vegan, gluten-free], rise in fast food and ultra-processed foods (*possibly problematic data: from individuals and groups linked to the food supplement industry, like the Proprietary Association of Great Britain PAGB).

Also problematic is the restriction of flour fortification to just milled white wheat flour if it is truly advantageous to all the population. A 2019 Portuguese study, while mostly in favour of flour fortification, demonstrated that a wider remit would be needed if all diets and socio-economic backgrounds were to benefit from it.

In favour of fortification are the Association of UK Dieticians; wary of it is The Real Bread Campaign. 

Regarding the proposed addition of folic acid, Dr Jonathan Sher (Senior Fellow at the Queen's Nursing Institute Scotland) argues that (a) yes, folic acid supplementation in the diet could be hugely beneficial during pregnancy, but that (b) “the government itself admits [its flour fortification plan] is only sufficient to avoid less than 22% of Neural Tube Defects” (one of the key targets that folic acid in the diet might aid), and that by "narrowly restricting the level and scope of folic acid fortification, ‘collateral damage’ will be experienced by those who don’t regularly (or ever) consume bread made with a single type of wheat flour".