Healthy Habits: Sun Protection and Vitamin D 

Summer is upon us and the sun is shining. With the warmer weather, we are more likely to be less covered with clothing and spend more time outside soaking up the sunshine. To prevent skin cancer and other skin damage caused by the sun it is important to use sunscreen and other sun protective clothing like hats. Yet the sun and its UVB rays are important for the production of Vitamin D. While there are food sources like eggs, dairy, some mushrooms, and fortified foods, our bodies produce most of this Vitamin D with the help of the sun that we need. In this blog, we will look at why Vitamin D is important, how sun protective measures impact the production and steps to ensure we are getting enough. 

Why is Vitamin D important?

Vitamin D, and specifically Vitamin D3, plays a key role in our bone health as it aids in the absorption of calcium.  This can prevent the softening of our bones at all ages, meaning that we can avoid ailments like rickets and osteomalacia.   It is a fat-soluble vitamin that is produced in our skin when it is exposed to UVB rays. Like many vitamins, they are needed for many of our body’s functions and maintenance. Vitamin D has beneficial impacts on our bodies including the aforementioned bone health, it has also been shown to be important in gene expression, diabetes, cardiovascular diseases,  cognitive degeneration, covid 19 immunity and more (1,2). 

How does sun protective safeguards impact the production of Vitamin D?

Sun protective measures are important to prevent skin cancers, UV-induced immunosuppression and skin aging. Preventing the damage done to the skin is important for all skin colours as skin cancer is just as possible in darker skin tones as in fairer skin tones. There is a mix of conclusions when it comes to the impact of sunscreen on Vitamin D production. Some studies say that sunscreen prevents the production while others say that that impact is not significant. This may come down to the amount, regularity and strength of sunscreen used as well as other protective measures that may also limit sun exposure. Those that are photosensitive use higher UV protective sunscreen, in larger or even the recommended amounts, seek shade and cover up with protective clothing and hats may not be getting the recommended amount of Vitamin D from the sun and would benefit more from supplementation. However, these measures also greatly reduce your risks of the aforementioned skin cancer and other skin damage. If you are the average person who may not use sunscreen at the recommended amounts, seek some sun exposure and have your hands, face and arms exposed for 5-15 minutes a day during the summer months you are probably getting sufficient amounts of Vitamin D from the sun. 

Steps to ensure that we are getting enough Vitamin D? 

While many foods are fortified  with Vitamin D, it is often in the form of Vitamin D2. This is good but it is the Vitamin D3 our body produces. Vitamin D3 comes mostly from animal sources although some mushrooms can produce Vitamin D3 when exposed to UV lights while growing, however, this is rare in the production of most mushrooms.  Vitamin D2 can be converted in our body to Vitamin D3 with some studies saying that it’s used in the same way with the same efficiency (2). The recommended daily allowance of Vitamin D is about 400 IU based on numbers from the FDA, other sources state that a higher intake closer to 1000 IU per day is more protective with an upper limit of 2000 IUs (4).  Supplementation can be helpful for many who might not be able to get enough sun exposure, but it does come with a low risk of taking too much. Taking too much is more likely in those who take supplements, compared to those getting it through primarily sun exposure and food. If you are worried always talk to your doctor. 

Getting enough sun exposure to meet your Vitamin D needs is much shorter than you might think. During the summer months when the sun is more intense, you only need a few minutes (5-15 minutes) of mid-morning or mid-afternoon sun to meet your needs. During the winter months, it can be about 2-3 hrs of exposure over a WEEK which is about 20 -25 minutes per day. This means having your face, hands and arms exposed for those times while stil using some sun protection to prevent sun burns and skin damage. 

With all this in mind enjoy the sun and the Vitamin D that it provides. 

Sources: 

1. https://www.youtube.com/watch?v=4VlXGA1FnSk
2. Borel, P., Caillaud, D., & Cano, N. J. (2015). Vitamin D bioavailability: state of the art. Critical reviews in food science and nutrition, 55(9), 1193–1205. https://doi.org/10.1080/10408398.2012.688897
3. Tran, V., Janda, M., Lucas, R. M., McLeod, D. S. A., Thompson, B. S., Waterhouse, M., Whiteman, D. C., & Neale, R. E. (2023). Vitamin D and Sun Exposure: A Community Survey in Australia. Current oncology (Toronto, Ont.), 30(2), 2465–2481. https://doi.org/10.3390/curroncol30020188
4. Raymond-Lezman, J. R., & Riskin, S. I. (2023). Benefits and Risks of Sun Exposure to Maintain Adequate Vitamin D Levels. Cureus, 15(5). https://doi.org/10.7759/cureus.38578

Cardwell, G., Bornman, J. F., James, A. P., & Black, L. J. (2018). A Review of Mushrooms as a Potential Source of Dietary Vitamin D. Nutrients, 10(10), 1498. https://doi.org/10.3390/nu10101498