Vitamin D has been a hot topic in recent years as more research looks at its potential health benefits beyond bone health. However, there is also controversy around whether using sunscreen blocks vitamin D production when you expose your skin to sunlight. Let’s explore the latest research on vitamin D, including optimal blood levels, sources, and the complex relationship with sunscreen use.
The Importance of Vitamin D
Vitamin D helps regulate calcium absorption for bone health. It supports healthy immune and nervous system functioning. Vitamin D is unique because your body makes it when you expose your skin to ultraviolet B (UVB) rays from sunlight. Only 10-15 minutes of sun exposure 2-3 times per week enables adequate vitamin D production.
While vital for bone health and calcium regulation, emerging research suggests vitamin D may provide other health benefits. These include reducing risk of respiratory infections, autoimmune conditions, cardiovascular disease, cancer, cognitive decline, and improving mood.
However, some studies show no effect, so we need more research, including randomized controlled trials, to clarify vitamin D’s role in these chronic diseases. Still, maintaining adequate intake through diet, sun exposure, and supplementation appears beneficial for overall health.
Sources of Vitamin D.
Since few foods contain or are fortified with vitamin D, sunlight is the primary natural vitamin D source for most people. Fatty fish like salmon and tuna contain significant amounts of vitamin D and you can get smaller quantities from egg yolks, liver, certain mushrooms, and fortified foods like milk and cereal.
But are you getting enough? Recent studies suggest the current recommended vitamin D blood levels may not be ideal for certain health outcomes like heart health. While the Institutes of Medicine recommends levels of 20 ng/ml as sufficient, experts argue that 30-60 ng/ml is optimal.
The relationship is complex though, as very high blood levels above 150 ng/ml can cause toxicity with symptoms like nausea, confusion, and kidney stones. Most experts agree maintaining a level between 30-60 ng/ml is ideal for health.
Getting enough vitamin D can be tough, especially in places with little direct sun exposure or during winter. People in these areas may need supplements for optimal health. Vitamin D3 raises blood levels more effectively than D2.
But what if you choose to get most of your vitamin D from exposing your skin to sunlight? There’s concern that using sunscreen could lead to low vitamin D levels since sunshine helps our skin make that vitamin. But interestingly, studies haven’t found that people who use sunscreen regularly are not deficient in D. There seem to be a couple of reasons for this.
First, most of us don’t put on enough sunscreen or reapply it as often as we should, so sun exposure still happens. And second, even though sunscreen blocks most UV rays, a little bit still gets through – enough to kick off vitamin D production. A study published in the British Journal of Dermatology found that people use sunscreen in such a way that it doesn’t have a significant impact on vitamin D production.
The truth is our bodies are efficient at making vitamin D when they get even lesser amounts of sun. So, while too much sun puts us at higher risk for skin cancer, getting moderate sun exposure with proper protection is unlikely to cause a deficiency. For most people, sunscreen and vitamin D go together fine. But check with your doctor if you have concerns about your levels.
Also be aware that by not wearing sunscreen, you run the risk of skin damage from ultraviolet light exposure.
Know Your Risk of Vitamin D Deficiency
If you’re at higher risk of vitamin D deficiency, you’ll need to focus more on getting enough vitamin D, either from sun exposure or supplements.
Some groups of people who are at higher risk for low vitamin D levels – those with darker skin, people carrying extra weight, folks living farther north, seniors, and breastfed babies. Health conditions like Crohn’s, celiac disease, and kidney disease also make it more challenging to keep vitamin D levels up.
The good news is, we have ways to stay on top of this. Getting blood tests to check vitamin D levels can help those at risk know if they’re dipping too low. If so, taking a vitamin D supplement is an easy fix to boost it into the normal range.
Your body is made to manufacture vitamin D from sunlight. If you can’t make as much – whether it’s due to skin tone, age, health conditions, or lifestyle – having your level tested and supplementing when needed helps ensure you’ve got sufficient stores of this important nutrient. Maintaining healthy vitamin D levels supports your bones, muscles, immunity, and more. So, work with your healthcare provider to make sure your levels are looking good!
In summary, vitamin D is essential for bone health but may also benefit immune function, heart health, and mood. Sunscreen use does not appear to cause deficiency in most people and moderate sun exposure can help maintain optimal blood levels between 30-60 ng/ml. If you’re at higher risk, test your level and supplement accordingly under medical supervision. While we need more research, current evidence suggests sufficient vitamin D intake from sun, food and supplements is vital for well-being.
- Neale RE, Khan SR, Lucas RM, Waterhouse M, Whiteman DC, Olsen CM. The effect of sunscreen on vitamin D: a review. Br J Dermatol. 2019 Nov;181(5):907-915. doi: 10.1111/bjd.17980. Epub 2019 Jul 9. PMID: 30945275.
- Mayo Clinic. “Vitamin D,” 2023. https://www.mayoclinic.org/drugs-supplements-vitamin-d/art-20363792.
- Passeron T, Bouillon R, Callender V, Cestari T, Diepgen TL, Green AC, van der Pols JC, Bernard BA, Ly F, Bernerd F, Marrot L, Nielsen M, Verschoore M, Jablonski NG, Young AR. Sunscreen photoprotection and vitamin D status. Br J Dermatol. 2019 Nov;181(5):916-931. doi: 10.1111/bjd.17992. Epub 2019 Jul 15. PMID: 31069788; PMCID: PMC6899926.
- Holick MF. Sunlight and vitamin D for bone health and prevention of autoimmune diseases, cancers, and cardiovascular disease. The American Journal of Clinical Nutrition. 2004;80(6):1678S1688S. doi:https://doi.org/10.1093/ajcn/80.6.1678s
- What we know about vitamin D and bone health – Bone Health & Osteoporosis Foundation. Bone Health & Osteoporosis Foundation. Published February 25, 2023. Accessed February 6, 2024. https://americanbonehealth.org/bonesense-articles/what-we-know-about-vitamin-d-and-bone-health/