Category Archives: B12

Patrick Holford, Alzheimer’s Disease, Homocysteine Tests and Supplements

Professors Patrick Holford and David Smith chose the Daily Record to announce their remarkable findings that Alzheimer’s Disease is preventable with just a “few simple diet and lifestyle changes”.

I may be new to Holford Watch but I am familiar with the Holford Test-Em Dose-Em style of Jeopardy. If the answer is, “Dose them with B vitamins” the question must have been, “What do you do after testing someone’s homocysteine levels?”.  And, what do you know, I think it has slipped its way into this article, masquerading as a “simple blood test”. Continue reading


Filed under Alzheimer's, B12, Brain Bio Centre, Holford, home test, homocysteine, patrick holford, supplements, vitamin B12, vitamins

Folic acid fortification and supplementation: further discussion

Holford has e-mailed me about folic acid fortification – objecting to some of the content of this post – and I’d therefore like to explain my position in more detail. I’m grateful to Holford for raising some interesting points, and will take this opportunity to respond to a few of them:

  • Holford argues that problems are “already occurring in the US where flour is fortified with folate at half the level proposed for the UK”. This is, technically, correct – the FSA plans to fortify UK bread flour with higher levels of folic acid than is mandatory in the US. However, the FDA insists that a wider range of US staple foods (e.g. rice and grits) are also fortified – meaning that the average folic acid intake in the US increased by 215-240mcg/day following mandatory fortification. It is estimated that fortifying UK bread flour as planned by the FSA will lead to the average folic acid intake by c. 78mcg/day [PDF file, p.7]*.
  • Holford argues that there is “no reason for us not to expect [similar problems] in Britain”. However, given that the FSA’s plans will increase UK folic acid consumption by just over 1/3 of what was achieved by compulsory fortification in the US, there is a very good reason to expect that any problems will be less pronounced.
  • Holford argues that “[t]he real issue we have to deal with is how to educate and nourish young women.” Certainly, this is important – there have been problems getting across the message that women who are (trying to become) pregnant should generally supplement with folic acid. However, I’m sure that Holford would agree that good nutrition is important for other groups, too. I’d also argue that folate consumption is valuable for the general population, as it may be linked to a reduced risk of cardiovascular disease and cancer (and a good folate intake is definitely important for older women with higher-risk pregnancies). While greens do not oxygenate your blood, the fact that some are a good source of folate is therefore another good reason to eat your greens.
    Holford states that “I do not recommend and continue to be opposed to folate supplementation on its own to any individual or group at risk of B12 deficiency”. I’m glad to hear this – it seems a pretty sensible position on folate supplementation. I would, however, suggest that Holford makes the risks of this clear on his website and web-store: I have e-mailed him to advise that he does so.
  • Holford argues that I mis-represent Morris et al’s AJCN paper. I fail to see how this is the case: I note, pretty uncontroversially I would think, that the paper finds that “high folic acid intake combined with inadequate B12 intake is related to cognitive impairment in older people”. To be very precise, the Morris et al paper concludes that “In seniors with low vitamin B-12 status, high serum folate was associated with anemia and cognitive impairment.” All the evidence suggests that eating more folate will – at least to a point – increase your serum folate level. An increase of c. 78mcg/day in folic acid consumption (caused by fortification) will not, in itself, lead to high folic acid consumption and will not in itself lead to high serum folate levels. My argument that “it is very unlikely the modest supplementation supported by the FSA is going to be a significant problem in itself” is therefore correct, and is also perfectly compatible with a reasonable interpretation of the Morris et all paper.
  • Holford argues that the problems caused by high folic acid consumption have “nothing to do with the source of folate, whether from diet, fortification or supplements, but to blood levels”. I’d note that the Morris et al paper focused on blood levels of folate – and was therefore only likely to show those risks/benefits associated with different blood levels. I’d acknowledge that there are certain risks associated with high serum folate levels – whatever way these are achieved. However, supplement use can play a very significant part in high folate intake levels: for example, Mulligan et al’s recent article has found (albeit in a relatively small sample) that 94% of the over-60s in their sample group with high folate intake used supplements. There’s an obvious link between eating lots of folate and high serum folate levels – supplements provide an easy means of eating lots of folate.

There are a few more issues around this which I might go into later – but this post is already a bit too long. At any rate, I hope it’s clear from the above why I would stand by my criticisms of the Guardian article on folate fortification. As John Nichols of the Royal College of General Practitioners puts it, I would acknowledge that “[t]here may be a case to be made against folic-acid fortification of bread and flour, but the stream of misinformation in [the Guardian] article is not it”.

* I haven’t had time to check these figures, but they seem about right and the FSA is clearly a reliable source.


Filed under B12, folic acid, health products for life, patrick holford, The Guardian

Patrick Holford letter to Holford Watch on Folic acid

Patrick Holford has e-mailed me, asking me to put his response to my post on folic acid and my letter in The Guardian on this blog. I’m happy to oblige, and welcome this opportunity to look at issues around folic acid supplementation and fortification in more depth. I’ve quoted his reply in full below, and I have also written a 2nd post to look at the issues around folic acid fortification and supplementation in more detail.

Jon – you’ve misrepresented the results of the research, published in the American Journal of Clinical Nutrition by Dr Martha Morris (, which clearly shows that those elderly in the US who have high serum folate levels, but are B12 deficient – estimated to be 4% of the elderly population – are already showing increased incidence of cognitive decline. This is a direct consequence of folate fortification, and is already occurring in the US where flour is fortified with folate at half the level proposed for the UK. So there is no reason for us not to expect the same thing in Britain. This has nothing to do with the source of folate, whether from diet, fortification or supplements, but to blood levels. It is quite wrong to imply that the risk would only relate to high dose supplements, but not to fortified food. Any doctor knows that folate can mask B12 deficiency and now we know that folate can exacerbate B12 deficiency associated cognitive decline. For that reason, I do not recommend and continue to be opposed to folate supplementation on its own to any individual or group at risk of B12 deficiency, however it has many benefits in combination with B12. The real issue we have to deal with is how to educate and nourish young women.

On another note, as you continue to attack my apparent lack of qualification to call myself a nutritionist despite 30 years in this field, perhaps you would care to explain what your qualifications are. I’m sure readers of your website would appreciate knowing.

Patrick Holford


Filed under B12, folic acid, fortification, patrick holford, The Guardian

Holford Watch letter in the Guardian – give us this day our daily scare story about ‘chemicals’

11Joanna Blythman was writing in Friday’s Guardian, discussing concerns about plans FDA to fortify UK bread with folic acid11. Discussing it badly. Really, really badly. And – to add to the excitement – using Patrick Holford as a source. I’m going to look at the article – and Holford’s contribution here.

I thought the article was so bad that I wrote a letter to the Guardian criticising it. And – credit where credit’s due – the Guardian has published the letter today. Read my letter here22 (along with an excellent letter from John Nichols of the Royal College of General Practitioners).

Naturally, I’m grateful that the Guardian published the letter – but there are more problems with the article than I could fit into a single letter to the paper (and – while whoever was editing the letter did a good job on it – they did edit out a little of what I had to say). I’ve also been in touch with Holford since the publication of the article (and since after I wrote the letter) and he’s kindly clarified a few of his points. I’m therefore going to use this post to outline some of the problems with Holford’s position, and to go into more detail about some of the points raised in my letter.

Firstly, if the Guardian wants to run an article on adding ‘chemicals’ to our food, it might help if they made sure that their writers know what a ‘chemical’ is. The article certainly appears confused about this (rather central) point: for example, Blythman refers to adding the “controversial chemical” flouride to our water supply.

My God! Chemicals in water! Next you’ll be telling me that there’s hydrogen in there, or even – shudder – dihydrogen monoxide33. One would hope that someone writing for The Guardian would know that water is a chemical (H2O) and that without access to such chemicals we would all die pretty quickly. We need chemicals all the time, not just daily.

Looking for a good source to quote on folic acid and fortification, Blythman chose to quote Holford – listing him as a “nutritionist”. I know Holford doesn’t have any accredited university degrees in nutrition – but ‘nutritionist’ isn’t a accredited title (I could quite legally market the duck in my local park as a ‘nutritionist’) so I’ll let that pass. However, Holford does have a number of competing interests in this area and it would have been appropriate to at least mention this – so that readers could take this into account when judging Holford’s statements. Especially given that Blythman has written at length44 about the distorting effects of the commercial interests of the supermarkets, it’s surprising that she doesn’t think that Holford’s commercial interests are worth mentioning.

Of course, if Holford’s science was sound then his commercial interests wouldn’t be so…well…interesting. However, I’ve got real problems with his arguments – problems which are exacerbated by the fact the Holford’s Health Products for Life makes money from selling folic acid supplements.

In the article, Holford argues that “We already know that folic acid, given without B12, is creating problems for the elderly…And that’s at half the amount that the FSA is proposing to add to British flour.” However, the FSA is proposing55 [PDF file; see p7] to add folic acid to our flour at pretty low levels: 300mcg/100g of flour; after the cooking of bread is taken into account, this “will increase the average folic acid intake of the population by about 78[mcg/day]”.

A high folic acid intake can mask the symptoms of B12 deficiency – something which, as Holford is right to note, is a particular problem for older people. However, the Scientific Advisory Committee on Nutrition has found that66 [PDF file; see p.53] “folic acid intakes up to 1mg/day are not associated with delayed diagnosis of vitamin B12 deficiency in older people.” The American Journal of Clinical Nutrition has found77 that high folic acid intake combined with inadequate B12 intake is related to cognitive impairment in older people (although good folic acid intake, alongside good B12 intake, brings cognitive benefits). However, although David Smith (writing in the same journal) urges caution88, it is very unlikely the modest supplementation supported by the FSA is going to be a significant problem in itself.

This is where Holford’s commercial interests become interesting. The SACN report99 argues that, at current levels of consumption, fortification of bread will increase “the number of people aged 65 years and over with low vitamin B12 status consuming more than 1mg/day of folic acid.” Supplement pills will play a key role here – anyone who wanted to shovel down enough (unfortified) food to eat 1mg of folic acid every day would need the constitution of an ox and a freakish love of spinach. An obvious way to avoid this risk is therefore for people to take fewer supplements. One likely consequence of the move to fortify bread flour is thus more prominent warnings about the need to avoid over-supplementation.

Holford’s Health Products for Life sells1010 folic acid pills (without B12). Holford advises that some people seeking to reduce their risk of Alzheimer’s should supplement with 2mg of folic acid per day1111. This is despite the fact that the Expert Group on Vitamins and Minerals has set1212 [PDF file] a safe Upper Limit (UL) for folic acid supplementation of 1mg/day (though a few groups – e.g. women with high risk pregnancies – may be advised to take more). 2mg/day is, however, not advisable for most of us.

So – Holford is quoted in a Guardian article emphasising the dangers of bread fortification (which could have a negative impact on Health Products for Life sales) but not even mentioning the much more significant risks from folic acid supplementation (Holford has a commercial interest in selling folic acid). Of course, one can’t know why Holford gives the advice he does – and had he given a balanced assessment of the evidence, I would not even need to be asking about him making money from pill sales. However, the rather skewed advice he was quoted giving does appear to serve his commercial interests surprisingly well – and I would therefore argue that the Guardian article should have made his commercial interests clear, in order to allow readers to decide for themselves whether they are relevant.

A note on measurement
1g = 1000 mg (milligrams) = 1,000,000 mcg (micrograms)


Filed under B12, folic acid, health products for life, patrick holford, The Guardian