Fitness & Health



Benefits and Adverse Effects of Sun Exposure

Ultraviolet rays from the sun can cause skin cancer. Sun exposure is vital in the production of vitamin D, which helps to protect against other types of cancer and illnesses. So, do we increase or decrease our daily sun exposure?

by / Published: 27 Mar 2019

Benefits and Adverse Effects of Sun Exposure
Photo: Unsplash

Benefits of sun exposure 
The sun helps our body produce vitamin D. Very few foods contain this vitamin, which is mainly found in fatty fish (salmon, tuna, mackerel), fish liver oils, egg yolks, dairy (milk, cheese), beef liver and mushrooms. Vitamin D facilitates the absorption of calcium and phosphate which are needed for healthy bones, teeth and muscles. It also prevents several illnesses including cancer, heart and autoimmune disease. 

In a review of studies done in 2014, breast cancer patients with a high level of vitamin D (more than 32ng/mL) at the time of diagnosis had approximately half the death rate compared to those with a low level of vitamin D (less than 14ng/mL). Colorectal cancer, prostate cancer, bladder cancer and Non-Hodgkin Lymphoma were also reported to benefit from sun exposure.

Sun exposure is also associated with the reduction of hypertension by UV ray-induced nitric oxide. By exposing the body to UVA radiation, the nitric oxides found in human skin are mobilised resulting in decreased blood pressure due to its relaxing effect on blood vessels. 

Besides vitamin D and nitric oxide, sun exposure is known to promote the production of melatonin, serotonin and regulates the circadian rhythms, which is our 24-hour internal clock. This promotes better sleep patterns and emotional well-being.  

Adverse effects of sun exposure
The adverse effects of sun exposure include the development of skin cancer and degenerative changes to the skin. Women who have had five or more blistering sunburns between the ages of 15 and 20 are more likely to have a higher risk (80%) of melanoma, which is the most aggressive form of skin cancer, than those who didn’t burn. Melanoma is a skin cancer that begins in the melanocytes, which are the cells that control skin pigmentation. Besides possible genetic factors, ultraviolet radiation from sun exposure and tanning beds is a main cause. Other skin cancers such as squamous cell carcinoma and basal cell carcinoma may also be associated with sun overexposure.

Limit or increase sun exposure? 
Knowing that the sun can cause degenerative changes and skin cancer is a great hindrance when it comes to sun exposure. But the relationship between melanoma and UV rays is two-sided. Non-burning sun exposure is associated with a reduced risk of melanoma, while sunburns are associated with a double risk of melanoma. Amazingly enough, it has been observed that outdoor workers have a lower incidence of melanoma than indoor workers.

The key word here is moderation. Without adequate sun exposure, you will deprive your body of its benefits while exposing yourself to the risk of vitamin D deficiency. Take the correct protective measures – wear sunscreen (at least 30 SPF), a hat and be careful with how much time you spend tanning and at what time of the day; also remember to moisturise after being in the sun to prevent degenerative damage. 

This article has been republished with permission from Hello Doktor