Folic acid in flour – is it necessary?

And why organic flour is exempt.

Since 2009 FSANZ (Food Standards Australia and New Zealand) have mandated that folic acid is added to white flour. The regulations also require that iodised salt is used in bread making. However certified organic flours and breads do not need to comply with this.

Why? Because Folic Acid is an additive and thus not allowable under organic regulations.

But, you may well ask, surely if it’s regulated, it must be necessary?

While folate occurs naturally in grains, you’ll get more folate by eating eggs, legumes, liver, and green vegetables. Which raises the question: is white flour or white bread the best option if you want to top up your folate levels?

How much Folate do we get from grains?

The whole wheat grain consists of about 14% bran, the hard outer shell of the grain, 83% endosperm (the starchy centre), and about 3% germ which is the sprouting part or the ‘embryo’ of the grain. It’s the germ which contains the most folate and other B vitamins with 2 tablespoons (28g) of wheat germ providing around 20% of your recommended daily folate, along with fibre, antioxidants, and other nutrients.¹

But if people mostly consume white bread they’re not getting anywhere near that level of natural folate because the germ along with the bran is extracted when milling white flour. Separating parts of the wheat grain has come about due to the enormous popularity of white flours. What is extracted from the refined flour is then sold as separate products: wheat germ and wheat bran. To not do this would mean that the miller is throwing away about a fifth of the edible grain. In fact, a good portion of what is extracted will end up in animal feed products.

By discarding the bran and the germ in favour of white flour the general population is missing out on the folate they once gained from eating whole grains and less refined flour.

Arguably, the main issue is that we’ve become so accustomed to eating soft and fluffy bread that we are depriving ourselves of folate!
The highest amount of natural folate in grains will be in wholegrain or in stoneground flours that still contain all the bran and germ, so it makes sense that it’s healthier to eat wholemeal bread. However, there’s another catch.

Not all flours are created equal and not all wholemeal flours are whole grain products.

Most conventional wholemeal flours used in commercial bread making, or sold on supermarket shelves, have been roller milled to a fine white flour with both bran and germ completely removed.

Having extracted the bran to make white flour, the millers then add some back in to make ‘wholemeal’ flour.

This is due to the baking characteristics of real wholegrain flours – they do not produce the soft and fluffy wholemeal bread you’ll find in plastic bags in the supermarket. Instead, the gluten behaves differently in whole grain flours and large commercial bread bakers would need to treat it differently, and in addition to the extra costs involved, the texture of whole grain bread makes it far less popular.

At this point I will add that due to Kialla’s milling process, even our white flours are different to conventional white flour. Read more here.

Why do we need to supplement folate?

Folate is essential for our health, and we cannot synthesise it so we must get it from our foods.
It supports metabolism and gene expression, and low levels are a risk factor for cardiovascular disease, some cancers, and cognitive dysfunction from birth (neural tube defects) through to senior years (Alzheimers disease).²

Probably the most important reason for fortification, as a public health initiative, is folic acid’s proven ability to prevent neural tube defects in newborn babies.
The benefits are tied to adequate consumption of folic acid prior to conception and in the crucial first weeks of embryo development, therefore, it’s important that a woman has adequate levels even before she knows she is pregnant. A 2023 study shows that flour fortification seems to be working, with a fairly small 14% reduction overall but a 75% reduction for indigenous babies since its introduction in 2009.³

In some ways it makes sense to mandate folic acid as an additive in flour because it replaces the folate extracted via by the milling process. Although, as mentioned above, folate can be found in many other foods and flours aren’t naturally the best source. Yet the problem from the perspective of public health is that many people still aren’t eating a variety of green vegetables (broccoli, avocados, brussels sprouts), or other high-folate foods like lentils and liver, but they are consuming plenty of soft white bread, pasta, and manufactured breakfast cereals.

Fortifying flour is convenient because, unlike green vegetables, the milling process offers the perfect opportunity for government food authorities to mandate additives.
And this is much easier than changing people’s eating habits or getting fresh produce into remote communities. 

By fortifying flour, medical authorities expect that long-term folic acid supplementation should reduce the prevalence of other folate-related diseases, not only neural tube defects.
Yet after more than twenty-five years of mandatory folic acid fortification in the USA, there are signs that it’s not that straightforward.

The general population may be low in folate for multiple reasons not only because of what we’re eating.

Some other causes include emotional stress, digestive dysfunction, and the way some prescription drugs or alcohol interact with folate. As well, a significant portion of the population have a genetic variant (known as MTHFR polymorphism) which impacts their ability to absorb folate.⁴

To complicate the usefulness of fortification as a public health intervention, more recent studies are indicating that adding this vitamin to flour may be creating new problems.

How is Folic Acid different to Folate?

Often the terms folic acid and folate are used interchangeably in medical information, and while these are both forms of vitamin B9, strictly speaking, they are not identical.⁵

There’s increasing evidence that our body recognises the difference and doesn’t process these substances in the same way.

The naturally occurring form of folate found in grains, leafy greens, liver etc, is a glutamate while folic acid is a glutamic-acid. Folate is absorbed and metabolised in the intestines, while folic acid needs to be converted to a body-friendly version of folate by an enzyme in the liver and this involves several steps.

Because folate is absorbed in the small intestine, absorption may be affected by digestive issues. The other issue is the instability of natural folate – even when we consume folate-rich foods we can lose anywhere from 40% (when cooking vegetables) to 70% (in milling and baking).⁶

Folic acid is more stable thus its usefulness for adding to food.

Therefore, folic acid seems a more sensible form for supplementation and is thought to be absorbed at twice the rate of folate. And as a water-soluble vitamin any excess should be excreted through the urine.

Over the last decade, however, concerns are being raised about how effectively our bodies are using the synthetic version.

Our livers aren’t set up to efficiently metabolise folic acid when consumed in large amounts.

Much of it ends up unmetabolised in blood serum and this may be creating its own issues.^{7 8}

The drawback of public health initiatives that utilise a one-size-fits-all supplementation is that this approach is unable to account for difference in individual capacities to convert folic acid.

Australia’s fortification guidelines are 2-3mg of folic acid per 1kg of flour.  This amounts to around 250mcg per 100g of bread (about 3 slices of standard white bread). While this is equivalent to the UK standard it’s double the 120mcg fortification standards the USA has been using since 1998.
The recommended RDA for folate is 300-400mcg.

Depending on whether people are getting folic acid from other sources such as multi-vitamins, on top of their intake of fortified breakfast cereals, pasta, and white bread, they may be getting far more than what is useful.

Also, pregnant women’s requirement for folate is higher, and it’s recommended that they take extra folic acid anyway, which can often result in consuming up to 1000mg in supplement form on top of what they’re getting through their diet.

Folic acid accumulates in the body over time

~ The amount of circulating unmetabolized folic acid depends not only on the dose taken but also on how much is taken over time. It accumulates when a person’s liver is unable to manage even repeated smaller doses.^{9 10}

~ A 2017 review noted that 1000mg daily intake from a pregnancy supplement will cause high levels of unmetabolized folic acid in the bloodstream, even if the doses are spaced apart in 100mg amounts.¹¹

~ For some people as little as 200mcg per meal can cause small amounts of folic acid to appear ‘unchanged’ in the blood circulation.
Concentrations then accumulate over time.^{12 13}

This is largely due to levels of the liver enzyme required to break down folic acid, which varies from person to person.

Low enzyme activity not only impacts the liver’s ability to transform folic acid into its bioactive form, but it may also affect the intestine’s role in absorbing it.¹⁴ 

And this can actually be harmful, particularly for those who have individual differences in the capacity of their liver to convert it, such as those with MTHFR gene variants (e.g., C667T variants),¹⁵ which is widely dispersed through the population.¹⁶

What does the science say about folic acid?

Much of the research over the previous forty years has been in animal studies and studies are now revealing that a rodents’ capacity to convert folic acid is up to 25x higher than humans.¹⁷ This new understanding needs to be taken into account when considering the positive influence of folic acid.

It appears that our livers are not designed to convert large quantities of folic acid, and concerns are being raised about the negative impacts of ummetabolised folic acid in the blood.

‘Unmetabolised’ Folic Acid suggests that it is being underutilised, but there are signs that it’s also being over utilised.

Not only does folic acid uptake depend on how well it’s converted into the bioactive form of folate, but it’s also now known that two out of three of the body’s mechanisms for transporting folate to where it’s needed are less able to control how much folic acid enters the cells. Because folic acid isn’t useful until it is converted, when it ‘competes’ with bioactive folate this could mean there is less bioactive folate available for metabolic processes that need it.¹⁸

Complex homeostatic processes in the body can be ‘confused’ or unbalanced by excessive folic acid, and this may explain the contradictory results seen in studies.

Over the two decades since mandatory fortification has been introduced into USA, studies in the population at large show cases where folic acid seems protective and other situations where it appears to be harmful. The difference in how the body treats folic acid compared to folate may be responsible for what one review referred to as the “Jekyll and Hyde” effects.¹⁹

Contradictions in the medical studies

Folic acid and cancer

While folate is protective against some cancers, high doses of folic acid may accelerate the progress of existing premalignant lesions.
One reason could be that unmetabolised folic acid is correlated to reduced effectiveness of “killer T-cells”, our immune system’s first line of defence against tumour cells.²¹

A similar conclusion was reached in a 2008 review of folic acid’s contradictory impact on cancer.

The authors say that while it’s not clear if excessive levels of natural folate have a similar impact, “dramatically increased folate status resulting from mandatory folic acid fortification and supplementation on cancer incidence in the United States and Canada is of great concern,” and urges caution in supplementation.²²

Folic acid and neurological health in seniors

The impact of folic acid supplementation on the neurological health of seniors shows similar contradictory effects. High serum folate appears to be protective only if the person’s vitamin B12 status is normal, while unmetabolised folic acid from excessive intake may mask underlying neurologic diseases associated with B12 deficiency.^{23 24}

High intake of folic acid has been associated with cognitive decline in seniors.
A 2007 review considers that potential harm is more of a problem than the potential benefits supplementation offers.²⁵

This is a particular challenge for those who have the MTHFR gene variant.

Folic acid and autism

As with cancer and Alzheimer’s, studies into the role of folate in Autism Spectrum Disorder (ASD) report contradictory effects from folic acid fortification.

With recommendations for pregnant women to take supplementary folic acid throughout pregnancy this may be related to how well the mother metabolises high doses over longer periods.²⁶

Folic Acid is clearly shown to prevent neurological issues in early pregnancy, and this is the primary reason for introducing flour fortification. However, it now appears that high levels of excessive blood serum folic acid may have a negative impact on neuron development in later stages of pregnancy.

This seems to be both tied to the role of folate in proper methylation of DNA and epigenetic expression, and the capacity for folic acid to be transported more readily into the brain than the bioactive form.²⁷

Although earlier studies have shown folic acid to be protective against autism, an autism review in 2017 concluded that folic acid is not the best form of folate to use and urges caution in supplementation.²⁸

With unmetabolised folic acid increasingly detected in umbilical cord blood newborns are already challenged from the outset, particularly those with MTHFR gene variants.²⁹

Once again, these contradictions may simply point to the challenges with a one-size-fits-all solution that cannot accommodate individual variations in our ability to deal with folic acid.

“Selective excess intake of one vitamin type may have the potential to negatively alter metabolic activities.”

Wiens D, DeSoto MC. Is High Folic Acid Intake a Risk Factor for Autism?-A Review.

One size fits all?

While public health initiatives to solve population-wide health issues are well meaning, this approach is looking increasingly out-dated as research shows nutrition to be a complex array of factors that cannot be solved by administering a single vitamin.

The authors of a 2023 study anticipate that folate supplementation must evolve from one size for all to more personalized treatments that meet individual needs, maximize health benefits, and minimize side effects.³⁰

Many nutritionists now recognise that food is medicine, and whole foods never contain singular vitamins – they host a plethora of nutritional co-factors. An example with folate is that its function in the body must be supported by adequate levels of vitamin B12 and Vitamin D3.³¹

And while individual vitamins can be effective in acute deficiencies, or specific circumstances, long term supplementation for all may unbalance body systems.

The authors of a 2017 review on the impact of folic acid on autism caution that “selective excess intake of one vitamin type may have the potential to negatively alter metabolic activities.”³²

Conclusion & Summary

Folate is essential for our health and is shown to be active in protecting us from a wide variety of chronic diseases and neurological issues. Food fortification has been able to reduce the incidence of folate-related diseases like neural tube defects.

While folate supplementation is clearly a good thing, particularly in cases of deficiency, is folic acid the best form to use?

Questions about how well many people can metabolise this synthetic form of vitamin B9 suggest it isn’t the best for population-wide supplementation.

While folic acid is more stable and therefore more suitable for food fortification, it must be converted in the liver to a bioactive form.
And this depends on the level of a particular enzyme in the liver.

High levels of folic acid in the diet can result in unmetabolised folic acid in the blood and there is increasing concern this is connected to various folate-related health issues.

Excessive amounts of unmetabolised folic acid may upset the balance of our body’s mechanisms for managing folate and delivering it to where it’s needed in the body.

The successful metabolism of folic acid also depends on several factors including gene variants in the population.

Recent studies and reviews are calling for caution when it comes to population-wide dosing.

Folate also works in synergy with other vitamins and co-factors and deficiencies in these may impact the effectiveness of mass supplementation, or even result in detrimental effects.

In short, yes, it is a good thing that certified organic flours are exempt from fortification. By eating organic flour and organic bread you get to choose how much extra folic acid you want in your diet.

And while you enjoy bread made with organic white flours, remember that it is important to ensure you source the folate your body needs through eating a wide range of foods.

Some examples include wholegrains, sunflower kernels, eggs, chicken and calf livers, to dark green leafy vegetables, avocado and citrus fruits (to name a few).

Please be aware that the contents of this blog are informative only and should not be taken as medical advice.
We recommend that you consult an integrative doctor, nutritionist, or naturopath for individualised support in respect to your own Vitamin B9 status.

Notes

1. Healthline.com: 15 Healthy Foods That are High in Folate (Folic Acid) ↩︎
2. Wright, A., Dainty, J., & Finglas, P. (2007). Folic acid metabolism in human subjects revisited: Potential implications for proposed mandatory folic acid fortification in the UK. British Journal of Nutrition. ↩︎
3. Thurston, L., Borman, B. & Bower, C. (2023) Mandatory fortification with folic acid for the prevention of neural tube defects: a case study of Australia and New Zealand. Childs Nerv Syst 39. ↩︎
4. Wright, A. et al. Op cit. ↩︎
5. Scaglione F, Panzavolta G. (2014) Folate, folic acid and 5-methyltetrahydrofolate are not the same thing. Xenobiotica. ↩︎
6. Milman N. Intestinal absorption of folic acid – new physiologic & molecular aspects. Indian J Med Res. ↩︎
7. Patanwala I, King MJ, Barrett DA, Rose J, Jackson R, Hudson M, Philo M, Dainty JR, Wright AJ, Finglas PM, Jones DE. (2014) Folic acid handling by the human gut: implications for food fortification and supplementation. Am J Clin Nutr. ↩︎
8. Wright, A. et al. Op cit. ↩︎
9. Powers, H. (2007). Folic acid under scrutiny. British Journal of Nutrition. ↩︎
10. Wiens D, DeSoto MC. (2017) Is High Folic Acid Intake a Risk Factor for Autism?-A Review. Brain Sci. ↩︎
11. Wiens D, DeSoto MC. Ibid. ↩︎
12. Powers, H. Op cit. ↩︎
13. Menezo, Y.; Elder, K.; Clement, A.; Clement, P. (2022) Folic Acid, Folinic Acid, 5 Methyl TetraHydroFolate Supplementation for Mutations That Affect Epigenesis through the Folate and One-Carbon Cycles. Biomolecules ↩︎
14. Patanwala I, et al. Op cit. ↩︎
15. Wiens D, DeSoto MC. Op cit. ↩︎
16. Menezo, Y.; et al. Op cit. ↩︎
17. Patanwala I, et al. Op cit. ↩︎
18. Menezo, Y.; et al. Op cit. ↩︎
19. Wright, A. et al. Op cit. ↩︎
20. He Q, Li J. (2023) The evolution of folate supplementation – from one size for all to personalized, precision, poly-paths. J Transl Int Med. ↩︎
21. Wright, A. et al. Op cit. ↩︎
22. Young-In Kim. (2008) Folic Acid Supplementation and Cancer Risk: Point. 
    Cancer Epidemiol Biomarkers & Prevention. ↩︎
23. He Q, Li J. Op cit. ↩︎
24. Scaglione F, Panzavolta G. Op cit. ↩︎
25. Wright, A. et al. Op cit. ↩︎
26. Powers, H. Op cit. ↩︎
27. Wiens D, DeSoto MC. Op cit. ↩︎
28. Wiens D, DeSoto MC. Ibid. ↩︎
29. Menezo, Y.; et al. Op cit. ↩︎
30. He Q, Li J. Op cit. ↩︎
31. He Q, Li J. Ibid. ↩︎
32. Wiens D, DeSoto MC. Op cit. ↩︎