Recently a couple of blogs have focused on the potential role that vitamin D may play in the regulation of body weight (see here and here). One of these blogs concerns a study which found that low. Levels of vitamin D were associated with increased body weight and waist circumference. This does not mean that vitamin D deficiency or insufficiency definitely causes fatty accumulation, but this possibility exists.
As a follow-on from this, I was interested to read about a study (as yet, unpublished) which assessed the relationship between vitamin D levels and weight loss on a reduced calorie diet (you can read about it here). In this study, conducted at the University of Minnesota in the USA, 38 obese men and women were put on a reduced calorie diet (750 calories less per day than their daily requirement) for 11 weeks. The researchers looked at the relationship between vitamin D levels and extent of weight loss in the study participants.
The report linked to above states that vitamin D insufficiency was noted in many of these individuals, which possibly reflects the previous research which suggests that vitamin D deficiency might have some part to play in the development of overweight/obesity.
However, perhaps more telling that this was the finding that there was a relationship between the vitamin D levels and the extent of weight loss: the higher the vitamin D levels, the greater the weight loss. Again, this study also cannot be used to conclude that vitamin D can assist weight loss. But it is another piece of evidence which ties vitamin D to body weight control.
What is required now are intervention trials in which the effect of supplemental vitamin D on body weight is assessed, either on its own, or as part of some weight-reducing regime (e.g. diet). If such studies show that vitamin D can promote weight loss, then we will have unearthed a potentially important factor in obesity. It will also help to explain why individuals can often find themselves lighter in the summer than in the winter.
You seem to have a much more open mind than many of the Doctor’s I encounter in the NHS.
It would seem to me that humans have evolved to produce vitamin D from sunlight, and that probably this is the most desirable way of obtaining it. Only modest amount are obtained form diet and modern farming methods combined with the prevaliling low fat high carb orthodoxy have combined to further reduce the contribution that diet can make.
Most adults in the UK spend insufficient time in sunlight to obtain anywhere near optimal lelves of vitamin D. Several ew factors have , I think combined to aggravate the position in the UK (and elsewhere). People with darker skin pigmentation produce less vitamin D in the UK (their pigmentation being better suited to warmer and sunnier climates) than is needed. The rising incidence of hey fever allergy means that many people limit exposure to sunlight when conditions are optimal for the production of vitamin D.
With regard to obesity/being overweight and its link to vitmain D deficieny this is a bit like the classic chicken and egg situation. Possibly in the past vitamin D was stored in the summer and released in the winter months – a kind of reversal of today’s bikini diet. I would speculate that overwieght people are generally less likely to expose their body’s to sunlight perhaps due to embarrassment, and this may limit their production of vitamin D.
Another hunch I have is that eating a high grain diet maybe impedes obsorbtion of vitaimn D (and other fat soluable vitamins). I became aware of suffering from hey fever around the time I started consuming wholegrains. I suspect you could plot a graph showing that the increased consumption of whole grains coincides with an increae in hey fever sufferers. I remember thinking about it at the time but never really contemplated not eating bread. Whole grains seemd to gain a hold around about 1980 if I remember correctly, or maybe around 1975.
Vitamin D from food seems to be more plentiful the further you are from the equator – the most extreme case being in the traditional artic communities. They seem to suffer when they swich to a typical western diet.
The problem with trials in this area is that there is precious lttle to be gained by pharmaceutical companies or indeed makers of sun screen lotions.
Going back to your earlier point about weight loss and vitamin D levels. Maybe we are genetically programemd to eat more when vitamin D levels are low, to store for when vitamin is scarce in the wfood and sunlight is scarce. Similarly we seem to be programmed to eat carbohydrates in the Autumn (fruit) for the winter. Perhaps the modern diet and predominantly indoor lifestyle is the exact opposite of what we require for optimal health.
From my example of 1, I have noticed weight loss, and less colds and infections since swiching to a low carb diet. So far this summer I have barely suffered from hey fever – even after spending an hour cutting grass. Maybe its just old age but I think the link between a no grain diet and hey fever is worthy of investigation.
Sorry for the rambling nature of this post.
Is there any truth to the claim that to be effective, D3 must be in liquid or powder form, not tablets?
I’ve been taking high doses of Vitamin D in capsule form for some time, have had my D3 blood levels tested twice – and found that that my D3 levels have doubled and then tripled.
There’s no problem with capsules. I get mine from http://www.bio-tech-pharma.com. This company is recommended by Dr Joe Prendergast (www.endocrinemetabolic.com). Dr Prendergast is a huge proponent of high Vitamin D levels. Sign up for his weekly video emails. They’re superb.
Didn’t I read that optimal levels of vit D make a person less hungry? That would be a big bonus with weight 🙂