Over the last one and a half years, you might have heard conflicting messages about the benefits of Vitamin D and also how to get enough sunshine to be healthy.
Vitamin D has been a controversial topic among scientists, mainly because most studies about its health effects have been so conflicting.
While vitamin D is important for many-body systems, including bones and the brain, recent studies that have tested these assumptions haven’t been reassuring, while some partially blamed use of sunscreen for widespread vitamin D deficiency worldwide.
To help clarify this issue, dermatologist Anne Marie McNeill detailed how vitamin D is synthesized.
“When your skin is exposed to sunlight, it manufactures vitamin D,” she said.
“The sun’s ultraviolet B (UVB) rays interact with a protein called 7-DHC in the skin, converting it into vitamin D3, the active form of vitamin D.”
McNeill assured that using sunscreen daily “can maintain their vitamin D levels”.
Addressing the misconception that sunscreen leads to a vitamin D deficiency, McNeill stated that research disproves this.
“Studies have never found that everyday sunscreen use leads to vitamin D insufficiency,” she asserted.
In contrast, there is “overwhelming evidence” for the multiple benefits of sun protection.
For example, applying an SPF 15 or higher sunscreen lowers the chance of melanoma by 50 percent.
“It has been proven on the molecular level that the sun’s ultraviolet (UV) light damages the skin’s cellular DNA, creating genetic mutations that can lead to skin cancer,” said McNeill.
Despite the fact, sunscreen is designed to filter out the sun’s UVB radiation – the same wavelength needed to create vitamin D – some rays still reach the skin.
“No matter how much sunscreen you use or how high the SPF, some of the sun’s UV rays reach your skin,” McNeill emphasized.
To explain, SPF 50 filters out 98 percent of UVB rays whereas SPF 30 keeps out 97 percent, and SPF 15 filters out 93 percent.
“This leaves anywhere from two to seven percent of solar UVB reaching your skin,” said McNeill. “And that’s if you use them perfectly.”
For those who are adamant unprotected sun exposure is the best way to get adequate vitamin D levels, they recommended “no more than 10 to 15 minutes of exposure”.
In addition, this is said to be “two to three times a week, followed by good sun protection”.
“That minor amount of exposure produces all the vitamin D your body can muster,” said McNeill.
Any more than that and sun exposure “is giving you nothing but sun damage”.
McNeill is unwavering in her stance, though. “Even just those unprotected 10 or 15 minutes are way more than enough time to cause DNA damage,” she said.
“Every bit of this damage adds up throughout your lifetime, producing more and more genetic mutations that keep increasing your lifetime risk of skin cancer,” McNeill concluded.
Her advice? “You can acquire vitamin D from a combination of diet and supplements. Fatty fish such as salmon, mackerel, and tuna are especially good sources.”