Vitamin D and Diabetes

There has been a lot of research on vitamin D and its relationship to diabetes, and it is relatively controversial amongst the scientific community. In pursuit of clarity for the diabetes community, here are some key takeaways on what vitamin D does in the body, how it relates to diabetes, and when to follow up with a health care provider.

What does vitamin D do?

A lot of things! Vitamin D helps the body absorb calcium and balance other minerals in the body, which help with bone growth and development. It also helps support the muscles, nerves, immune system, and glucose metabolism.

How do I get enough vitamin D?

The most effective way of getting vitamin D in your body is through sunlight, and there are not many foods that naturally contain vitamin D. Most people get vitamin D in their diets through fortified food, specifically milk and cereals. It is also found in yeast, some mushrooms, fatty fish and cod liver oil. If you’d like to read more, click here.

What’s the research on vitamin D and diabetes?

It’s complicated, but the basics are it is possible that low vitamin D is associated with type 1 diabetes. Low vitamin D has been linked to both insulin resistance and the auto-immune process. Since type 1 diabetes is an auto-immune disorder, it’s possible that vitamin D has a role in the activation of the onset of T1D, but the studies have not been entirely conclusive. However, there are many studies that show that early supplementation of vitamin D can prevent or delay the onset of T1D, as well as prevent type 2 diabetes.

For type 2 diabetes, vitamin D was proven in multiple randomized controlled trials to improve A1C, insulin resistance and insulin levels. Another study in 2017 showed that women with type 2 diabetes who had significant depressive symptoms had improvement in their depression and anxiety symptoms with a weekly oral vitamin D treatment.

Are there any symptoms of vitamin D deficiency?

There are a few key symptoms to vitamin D deficiency, but often it goes unnoticed. The most common symptoms are:

1. Getting frequent infections or colds
2. Back or bone pain
3. Fatigue
4. Low mood or depression
5. Wounds that don’t heal
6. Hair loss
7. Muscle pain

Why are vitamin D levels low in many people with diabetes?

The number of people with low vitamin D levels has been increasing worldwide, and most researchers and medical professionals attribute this to changes in the lifestyles of people and decreased sun exposure. There are more people with low vitamin D in locations in the world that are farther from the equator.

One other important thing to note is you are at higher risk of having a vitamin D deficiency if you have darker skin because people with darker skin do not absorb as much of the vitamin D from the sun. People with darker skin therefore require more time in the sun to absorb adequate vitamin D. See more here.

How do you check vitamin D levels?

Vitamin D should be checked with a blood draw, and it can sometimes take longer than other blood tests to get the results back. If you have diabetes, your doctor should be checking your levels routinely on a yearly basis.

What should I do to make sure I don’t have low vitamin D levels?

The American Society for Bone and Mineral Research put out a joint statement in collaboration with the American Association of Clinical Endocrinologists, among other organizations, with recommendations on prevention of low vitamin D. Their recommendations are primarily getting 15-30 minutes of direct sunlight daily on your skin and if unable to do this or consume foods with fortified vitamin D, to consider supplementing. We recommend consulting your health care team before making the decision to take a supplement.

What about SARS-COV-2 and Vitamin D?

Since vitamin D plays a role in immunity, during the beginning of the global pandemic of SARS-COV-2 (aka COVID-19) researchers hypothesized that it could help prevent complications or help improve outcomes in patients with the virus. The Lancet published an article in May 2020, that states based on a meta-analysis from 2017, taking vitamin D helped prevent acute respiratory tract infections which are common results of the COVID-19 virus.

In the most recent publication of the Journal of Infection and Public Health from this month, the conclusion of reviewing the most current research is that we need more data. They do say, however, that if people have severe low vitamin D taking supplements is recommended.

Clinically reviewed by Marissa Town, RN, BSN, CDCES