Is there a link between sun exposure and gut health?

The ill-effects of the sun's rays have been drilled into our minds by now. Some of us are so protective about our skin that we almost bathe in sunscreen before stepping out. Exposure to harsh sun rays (ultraviolet or UV rays) can burn our skin - causing tan, wrinkles and even cancer. But does that mean we’re losing out on the benefits of sunlight? 

New research published in the peer-reviewed journal Frontiers in Microbiology claims that skin exposure to ultraviolet light can improve gut health. The study points out that ultraviolet rays are essential for the synthesis of vitamin D - which in turn ensures the growth of healthy microorganisms living inside our intestines. These microorganisms prevent inflammatory bowel disease.

Representational image. Image by marcisim from Pixabay

Sunshine vitamin

Vitamin D (also called the sunshine vitamin) is essential for healthy bones and strong teeth. But the process of vitamin D synthesis requires two things; first, cholesterol and second, ultraviolet B (UVB) rays. Both of them have got a bad reputation.

The sunshine vitamin also plays a significant role in modulating the immune response by making the immune cells more effective and functional. In the case of vitamin D deficiency, the risk of developing autoimmune diseases increases.

The research

The previously mentioned study was conducted by Canadian researchers on 21 healthy women during winter days when they were not exposed to UV rays except for the experiment, although a few of the participants were on vitamin D supplements before the study.

The result of the study indicates a substantial increase in vitamin D levels of the participants with sun exposure. As the sunshine vitamin levels went up in the body, microbial diversity in the gut also improved a lot.

Benefits of gut microbes

In chronic inflammatory diseases such as inflammatory bowel disease (IBD), our own immune cells (that are supposed to protect us from diseases) attack the intestinal cell lining as well as the residing beneficial microbes in the gut. The result is - inflammation and sores or ulcers in the gut lining.

The study demonstrates that sun exposure essentially plays a vital role in protecting the good bacteria of the intestine, thereby preventing or at least limiting diseases like ulcerative colitis and Crohn’s disease (the two main types of inflammatory bowel disease).

Steps to take

Where on one side, ultraviolet rays are bad for our skin, they are also essential for maintaining good digestive health. Now, the question is, how to cut the bad effects of UVB but keep all the good ones? Here is what you can do:

• Take vitamin D supplements if your skin is too sensitive to sunlight.
• Step out in the morning sunshine for 20-30 minutes when the sun's rays are not harsh on the skin.
• Eat healthy foods - good fats such as avocado, fish and olive oil.

Health articles in Firstpost are written by myUpchar.com, India’s first and biggest resource for verified medical information. At myUpchar, researchers and journalists work with doctors to bring you information on all things health. For more information, please read our article on how to improve digestion.