Diabetes Forecast

Soak Up the Sun: Catching Rays May Work Better Than Taking Vitamin D to Prevent Obesity

What to Know

Many people do not get enough vitamin D, and low levels of vitamin D have been linked to obesity, which raises your risk of type 2 diabetes, heart disease, stroke, and many other serious health problems. The body produces vitamin D when skin is exposed to the sun. Supplements are another source of vitamin D. But what’s the best way to get vitamin D? And does an adequate amount help prevent obesity and risk factors for other serious health problems?

The Study

Researchers fed mice a high- or low-fat diet that either did or did not contain vitamin D supplements. Using lamps that mimicked sunlight, the researchers exposed some mice to low levels of sunlight and others to high levels. Finally, they applied a nitric acid cream, which reproduces the effects of sunlight, onto some of the mice. They then compared the various groups of mice to determine the different treatments’ effects on weight and other health measures.

The Results

In mice fed a high-fat diet, both low and high levels of continuous sunlight exposure prevented weight gain and controlled other health risks such as high blood pressure, high blood glucose, and cholesterol problems. Vitamin D supplementation offered fewer benefits, with or without sun exposure. The mice treated with nitric acid had many of the same benefits as the sun exposed mice.


Time in the sun and/or nitric acid creams may help prevent obesity and other health problems, though study in humans needs to be done to confirm this. Keep in mind that excessive sun exposure increases the risk of certain skin cancers.

Ultraviolet radiation suppresses obesity and symptoms of metabolic syndrome independently of vitamin D in mice fed a high-fat diet, by Geldenhuys and colleagues. Diabetes 2014;63:3759–3769 https://doi.org/10.2337/db13-1675

The information on this screen does not take the place of care from your doctor or other health care provider. If you have general questions about diabetes or diabetes-related research, e-mail askada@diabetes.org or call 1-800-DIABETES (800-342-2382).



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