Vitamin bashing is a popular sport among those who have not studied, witnessed or experienced the benefits of taking vitamins and associated cofactors at levels over and above those found in an average diet. The words in the preceding sentence were of course carefully chosen; the ‘vitamins’ to which we refer may be naturally-occurring in foods, or they may be synthetic but associated with cofactors and other bioactive compounds and enzymes in plant foods.
We also know that today’s ‘average diet’ differs greatly from that with which we evolved and typically has an imbalanced delivery of carbohydrates, fats and proteins, is too high in Omega 6 compared with Omega 3 fatty acids, and is deeply deficient in a plethora of nutrients needed to control and balance the multiple and interacting metabolic systems required to keep us healthy, vital and bounding with life.
Food is information
Nutritional science is helping us to realise that food is fundamentally a form of information for the body. A single, healthy meal with a bountiful supply of plant foods may contain many thousands of discrete naturally-occurring compounds that do a lot more than just provide energy to fuel the body. The three main macronutrient groups, carbohydrates, fats and proteins, can all be used as energy sources. But the micronutrients, that may include essential fatty acids, plant (phyto-) nutrients, various fibres, enzymes, amino acids and other compounds, are needed to keep our bodies, despite changing environments and different forms of stress, in an equilibrium state (homeostasis). That’s not only through the effect they have on our own cells, but also how they affect the microbes in our gut that outnumber human cells 10 to 1.
Many of these bioactive compounds in our food act as signalling compounds that help regulate metabolic pathways.
Very importantly, the quality of our diet affects the way in which our genes are expressed through epigenetic processes such as DNA methylation and histone modification that turn on or off particular genes, or for that matter, make some whisper or shout loudly.
It is of course not our genes themselves that control our destiny, but the ways in which they are expressed. Interestingly, these modifications can also be transmitted to subsequent generations (at least 3 or 4). The rapidly emerging discipline of epigenetics reinforces diet and lifestyle-based medicine as probably the most relevant form of medicine today, especially when our greatest health burdens relate to chronic, degenerative diseases like cancer, heart disease, type 2 diabetes and obesity, that are themselves so often triggered by long-term patterns of poor diets and lifestyle choices.
Vitamin D attack
Tim Spector, Professor of Genetic Epidemiology at King’s College London – and author of The Diet Myth – seemed like an unlikely candidate to test his hand in the sport of vitamin bashing last week. He chose to do it in an article published in the Independent newspaper. Prof Spector is no newcomer to the field of epigenetics. He has spent years researching the subject through his studies of identical twins and wrote a book about it that was published in 2012. But last week he made a dig against vitamin D supplementation. In the piece he says; “I used to sometimes take vitamin D myself and recommended it to my family to survive sun-starved winters.” Referring to an editorial published last week in JAMA Internal Medicine, JAMA being well known for its anti-supplement editorial stance, he cites, “However, a new paper on the risks that vitamin D may pose finally has convinced me that I was wrong.”
Prof Spector has done himself a disservice. He appears to have it in for supplements, regardless. In his books and talks, he will happily condemn junk foodies who don’t eat enough foods containing naturally occurring vitamins and minerals, including vitamin B cofactors like choline and betaine that act as epigenetic markers. By contrast, he’s critical of high dose folic acid supplements, arguing they may cause cancer or adversely affect the brain. Perhaps revealing some of his anti-supplement colours, he remains silent on the lack of risk associated with supplements containing high doses of the reduced (bioactive and natural) form of folate, 5-methyltetrahydrofolic acid.
But his latest attack on vitamin D is unfounded. His article in the Independent links directly to an anti-vitamin D editorial by Dr Steven Cummings et al that reverts to recommending a paltry 800IU (20 mcg)/day, or just 4 times the EU recommended level (200IU/5 mcg), the key paper by Dr Heike Bischoff-Ferrari et al in the same journal did not compare vitamin D supplementation against un-supplemented controls. It was a randomised controlled trial comparing 3 pharmaceutical treatments, involving monthly doses that were between 120 and 300 times the EU recommended level, among a Swiss population comprised two-thirds of women with an average age of 78. The trial found that the highest dose resulted in no benefit in terms of reduced fracture risk and that it did contribute to an additional risk; risk of falls.
There were no untreated controls as the researchers were targeting an elevated blood level of circulating 25-hydroxyvitamin D that can only be achieved with exposure to sunlight or by taking supplements or fortified foods.
In our view, using either the editorial by Dr Cummings and colleagues, or indeed the work of Dr Bischoff-Ferrari and colleagues, both published last week in JAMA Internal Medicine, to can vitamin D supplement use among the elderly will do more harm than good. That is because it is both a distorted view of the science that it cites, and secondly, it generates media chatter that will likely encourage many older people to be wary of vitamin D supplements and even stop taking them altogether. Neither the editorial, which proposes far too low a dose of vitamin D, or the clinical trial paper itself, argued against the use of supplements. Tim Spector could have so easily been more objective about the totality of the evidence and recommended that blood levels be tested to inform the supplementation regime if this was needed.
To supplement with nutrients or not
In many cases food is the best way of getting nutrients the body needs because of the complex matrix it offers to the body. Those cofactors and bioactive compounds do really make a difference, even if we don’t know how all of them work, especially in concert with one another.
But few of us can always ingest, consistently and in the long-term, a really diverse diet. That’s where supplements come in, they being simply a generic term for concentrated forms of nutrients delivered in dose form.
They can range from dried food concentrates through to isolated, synthetic nutrients.
The only supplements that have been demonstrated not to be beneficial are very high dose, synthetic, isolated or limited combinations of a small collection of vitamins, namely beta-carotene, vitamin E (as alpha-tocopherol) and folic acid.
Their natural equivalents, all increasingly used as supplements, cannot be tarnished with the same brush when used responsibly. In fact, as vitamins are unable to be made within our bodies, we can’t live without these essential nutrients.
When it comes to vitamin D, supplements are needed by the vast majority of the adult population not exposing most of their bodies to significant direct sunlight during the winter months. Darker skinned people are more at risk of vitamin D deficiency. A typical dose range that helps optimise circulating levels of 25-hydroxyvitamin D is between 2000/4000 IU (50-100 mcg) daily.
In addition, supplementing with adequate vitamin K2, magnesium and other nutrients is vital. But that’s another story for another time