How Vitamin D Can Benefit Diabetes Sufferers

| January 26, 2012

Getting enough vitamin D has long been known to be important for growing strong bones; the classic deficiency disease is rickets in children and is called osteomalacia when it occurs in adults. In recent years, vitamin D has been the subject of a massive amount of research, which has shown that it is also essential for the proper functioning of the immune system and helps prevent cancers and cardiovascular diseases.

While these two top killer diseases have understandably been given centre stage in vitamin D’s health benefits, another association has been much less publicised – that of vitamin D and diabetes.

Several research studies have shown that low levels of vitamin D are linked to the development of insulin resistance and diabetes. In a meta-analysis of 19 separate studies, published last September, US scientists at Tufts Medical Centre in Boston, concluded that people with the highest vitamin D status had a 43 per cent lower risk of developing type 2 diabetes, compared to those with the lowest levels of the vitamin. This lends support to the finding of a 2008 review, that adequate intake of vitamin D may prevent or delay the onset of diabetes, as well as reducing complications for those who have already been diagnosed.

Only last month, a new study found that obese children with lower vitamin D levels have higher degrees of insulin resistance, further suggesting that vitamin D deficiency may play a role in the development of type 2 diabetes.

So, what’s going on?

Well, the first thing to understand about vitamin D is that it isn’t really a vitamin at all; that is to say it is not an essential factor in the diet, like vitamin C. We make vitamin D in our skin in the presence of sunlight and chemically it is a secosteroid, very similar to the body’s steroid hormones, such as cortisol. Like those hormones, vitamin D locks onto receptors on the surfaces of many types of cells and influences their activity.

A Finnish study has found a clear link between vitamin D intake during the first year of life and the subsequent development of type 1 diabetes. Babies given 2000 IU of vitamin D daily were at significantly lower risk of developing the disease. In type 1 diabetes, the immune system destroys the body’s own pancreatic beta-cells, which produce insulin. Recent research suggests that vitamin D is instrumental in the production of regulatory T-cells, which instruct the immune system not to attack the body.

The way that vitamin D works to prevent type 2 diabetes is different. In this case, it both promotes insulin production and maintains the sensitivity of cells to insulin. Vitamin D has a direct action on pancreatic beta-cell function and also regulates blood calcium levels, which in turn influence the rate at which insulin is produced and secreted. Deficiency of vitamin D is a contributory factor in insulin resistance and glucose intolerance. In one clinical trial, vitamin D supplementation reduced susceptibility to type 2 diabetes by slowing the loss of insulin sensitivity in people showing early signs of the disease.

Vitamin D is not only important for helping to control blood sugar and insulin levels. It can also help to bring down high blood pressure and triglyceride levels and reduce the build-up of arterial plaque, all of which are risk factors for heart disease and are common complications of diabetes. Vitamin D also appears to be involved in the body’s weight control and fat metabolism mechanisms. A study has shown that low levels of vitamin D correlate with a higher body mass index and more body fat.

Is vitamin D supplementation a good idea for people with diabetes?

To my mind, taking a vitamin D supplement is a good idea for everybody in the UK, where we just don’t get enough strong sunshine for our bodies to make all the vitamin D we need (and many of us avoid the sun anyway because we’re worried about skin cancer!). For people with diabetes, I consider vitamin D supplementation to be an essential part of managing the condition and avoiding its dangerous complications.

Currently, there is no official guidance on how much vitamin D people with diabetes should take. The Department of Health recommends that pregnant and breastfeeding women, people who are not exposed to sunlight and people over 65 should take10 micrograms (equivalent to 400 IU) per day. This is not enough to provide for the body’s needs without adequate sun exposure, which few of us are able to get.

I take a supplement of 2000 IU a day and I would advise you to do the same. There are several chemical forms of vitamin D. The one to buy is vitamin D3, also known as cholecalciferol or calcitriol. In addition, on those days when the sun does shine, try to get 20 minutes of skin exposure without sunscreen. Eating oily fish is the best way to get extra vitamin D in your diet and it will also provide essential omega-3 fatty acids that have multiple health benefits, including lowering the risk of heart disease.

In my next blog post, I want to look at the relationship between diabetes and being overweight and investigate why thin people get diabetes, too!

Wishing you the best of health,

Martin Hum
PhD DHD Nutritionist
for Real Diabetes Truth

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3. Olson ML, Maalouf NM, Oden JD, White PC, Hutchison MR. Vitamin D Deficiency in Obese Children and Its Relationship to Glucose Homeostasis. J Clin Endocrinol Metab. 2011 Nov 9. [Epub ahead of print]

4. Hyppönen E, Läärä E, Reunanen A, Järvelin MR, Virtanen SM. Intake of vitamin D and risk of type 1 diabetes: a birth-cohort study. Lancet. 2001 Nov 3;358(9292):1500-3.

5. Bock G, Prietl B, Mader JK, Höller E, Wolf M, Pilz S, Graninger WB, Obermayer-Pietsch BM, Pieber TR. The effect of vitamin D supplementation on peripheral regulatory T cells and β cell function in healthy humans: a randomized controlled trial. Diabetes Metab Res Rev. 2011 Nov;27(8):942-5.

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Category: Vitamins and Nutrients

Comments (1)

Testimonials are based on the personal experience of individuals. Results are not typical and the potential benefits of taking any drug or supplement may vary depending on your individual needs and health requirements. Please consult your GP before making any changes to your medical regimen.

  1. MARTIN , interesting page , you will like the latest NEXUS MAGAZINE article on Vit D 3 out now . I would like to talk / meet up for educational ideas exchange . Do you talk at lectures / guest speaker events ? Trust you find this info useful.