Back in March I wrote a blog which explored the concept that low levels of vitamin D may predispose the body the fatty accumulation. Part of the evidence for this comes from a couple of studies [1,2] cited in the blog which found this association in female teenagers and women aged 16-22 respectively. More recently, further research has emerged that appears to support this potential link.
In a study published in the journal Obesity last month, Spanish women aged 20-35 were divided into two groups according to their vitamin D levels . Women with a vitamin D level of less than 90 nmol/l (36 ng/ml) were classified as ‘low D’ (LD), while women with a level of 90 nmol/l or more were classified as ‘high D’ (HD). Certain body measurements were then compared between the two groups.
The results of this study showed that body weight, body mass index and waist circumference were all higher in the LD group.
The average of each of these measures for LD and HD groups were:
Body weight: 76.2 and 68.6 kg
BMI: 28.6 and 26.0 kg/m2
Waist circumference: 86.2 and 79.4 cm
The first two of these measurements are, to my mind, pretty useless as they tell us nothing about the body’s composition or the distribution of any excess fat. The waist circumference is more useful, though, in that it is a proxy for excess weight congregating around the midriff (the form of excess weight most strongly associated with chronic diseases such as heart disease and type 2 diabetes).
The vitamin D intakes were similar between the two groups. The authors concluded that overweight/obese women are at higher risk of vitamin D deficiency, largely due to excess adiposity rather than inadequate intake. It is possible that being overweight increases the risk of vitamin D deficiency. For example, overweight and obese individuals may, for instance, get less sun exposure. Maybe they tend to go out less. Maybe they tend to wear more clothes when they do go out too.
However, the converse may be true too: vitamin D deficiency may cause individuals to put on weight.
A third possibility is that the association between vitamin D and body is just that ” an association ” and there is no ‘causality’ going on here one way or the other.
I am not aware of any science that demonstrates for certain that vitamin D deficiency can cause fatty accumulation in the body. However, what is becoming clear is that vitamin D has a role in many key body processes, also appears to have an influence in the development of and protection from a myriad of conditions. If it turns out that vitamin D does indeed influence body fatness, I won’t be surprised.
1. Richard Kremer, et al. Vitamin D Status and Its Relationship to Body Fat Final Height, and Peak Bone Mass in Young Women. J Clin Endocrinol Metab 2009;94:67″73
2. Foss YJ. Vitamin D deficiency is the cause of common obesity. Medical Hypotheses 2009; 72(3):314-321
3. Rodríguez-Rodríguez E, et al. Vitamin D in Overweight/Obese Women and Its Relationship With Dietetic and Anthropometric Variables. Obesity 2009;17(4):778″782
In Paleo terms, it makes perfect sense that Vitamin D would affect fat storage.
When cloudy weather starts in October, the resulting drop in Vitamin D would signal the body to store fat for the coming winter when food would be more scarce.
In the spring when sunny weather returns, the increase in Vitamin D would signal the body to stop storing fat as food would become more abundant.
Firstly I am a big fan of Vitamin D but I would love to know how the study concluded “The vitamin D intakes were similar between the two groups”. Did it just look at dietary intake?
The vast majority of our Vitamin D is made by our skin when in sunlight rather than obtained through diet (espec in country like Spain)
I imagine it may be quite tricky to control for vitaminD skin production from sunlight exposure as that would be difficult to measure and efficiency of production varies from person to person depending on skin pigmentation etc..
Isn’t this study really saying that people who in general spend more time outdoors are less fat than those who do not …we can all think of a myriad of reasons for that!
Jake, nice one! Possibly, more weight to the argument postulating seasonal metabolic dynamism as being important in the past and a key component of demystifying the present. Remember, in the autumn and in a natural habitat the availability of sugar rich ripe fruits increases upon which to gorge so there is a trend to seasonally raised aggregate dietary GL during autumn. In the past, this could effectively facilitate adipose deposition as preparation for the onset of winter.
What does this mean to us now? If by virtue of us all ‘living under a cloud’ by passing so much of our lives indoors, and always eating a sugar and refined carb diet of high GL then we are permanently living life in ‘autumn’ and constantly fattening ourselves for the shortages of winter that never come.
What do we need to do? Include more of the plant foods of ‘spring’ in the diet, perhaps?
In the ‘paleo’ sense as you refer, the seasonal availability during spring would shift towards young, tender, green leaves. This lowers GL significantly as greens are generally a good balance of carb and protein though not especially rich or dense in either. All that soluble fibre has implications for gut health too.
In our household we endeavour to begin a meal with a green salad, then follow with a main with around half the rice/potatoes/pasta than previous, and bulk out with additional veg. Result, 7 kg lost in around 5 months without sweating or really trying; no counting of calories, and absolutely no preoccupation with avoiding fat.
One thing though, unbalanced and omega 6 rich oils are avoided at all costs. Cold pressed rapeseed or grass fed butter is preferred for cooking, and olive oil or hemp (‘Good Oil’) is preferred for dressing. In this way, by avoiding pre-prepared and convenience foods we have signifacantly addressed the n6:n3 (omega) balance of our diet fro the better. We consider even the ‘best’ margarines to be unnatuarally rich in n6 and they have no place in our fridge. Given the Mente review, we stock our fridge with butter and use it guilt free in modreation.
Dr Briffas book, ‘The True You Diet’, and one work of Barry Sears, were the catalyst behind these changes and are highly recommended.
Mente reviewdiscussed here; http://www.drbriffa.com/blog/2009/04/17/no-evidence-that-saturated-fat-causes-heart-disease-its-official/
D3 is fat soluble, is it plausible that people with greater reserves of fat have more of the D3 stashed away in the fat rather than being bioavailable?
It is very true that obese folk have lower vitamin D levels as it is bound up in their adipose tissue depriving the body of a supply. Take a look at http://www.vitamind3world.com for some good summaries. The site also offers a good newsletter
Is it possible that the obese have incipient type 2 diabetes and that’s lowered their Vitamin D levels.
Relationships of low serum vitamin D3 with anthropometry and markers of the metabolic syndrome and diabetes in overweight and obesity
“The inverse relationship of vitamin D3 with high to extreme HbA1c [24,25] and/or FPG [7,8] may indicate that it is the long-term, severely abnormal (carbohydrate) metabolism of TIIDM [7,26,27] and muscle insulin resistance , that is associated with hypovitaminosis D3. HbA1c, a glycated protein, is a predictor of 2-hour glucose in oral glucose tolerance testing,  an indicator of chronic hyperglycaemia, protein glycation damage  and oxidative stress . Many new, profound and interacting mechanisms link hypovitaminosis D with other correlates of the metabolic syndrome, including renin regulation . Vitamin D-upregulated protein-1 reportedly modulates endothelial oxidative stress, macrophage and smooth muscle function, depending on the stage of atherosclerosis”
What is a ‘natural’ level of vitamin D? Mad dogs and ….
My sister-in-law (62 yrs) has suddenly put on a huge amount of weight, predominantly around her midrif. She had had a hysterectomy several years ago and had a hormone implant.
About 18 months her gp had stopped her HRT and gave her strong antibiotics for a chest infection. After which she had a health crisis with many allergic-type reactions, severe body pains and lethargy/ food sensitivities/systemic candida symptoms etc. She had now been to see an eminent Gynaecologist who a has prescribed HRT patches and the weight is piling on. HELP! I have suggested Vit D as a possible remedy which she has started taking. What is your opinion? Her GP is not helpful or sympathetic.