How To Safely Get Vitamin D From Sunlight
Vitamin D is a unique vitamin that most people don’t get enough of and is essential for good immune health. This vitamin is made from cholesterol in your skin when it’s exposed to the sun. That’s why getting enough sunlight is very important for maintaining optimal vitamin D levels. However, too much sunlight comes with its own health risks. This article explains how to safely get vitamin D from sunlight.
The Sun Is Your Best Source of Vitamin D
There’s good reason why vitamin D is called "the sunshine vitamin". When your skin is exposed to sunlight, it makes vitamin D from cholesterol. The sun's ultraviolet B (UVB) rays hit cholesterol in the skin cells, providing the energy for vitamin D synthesis to occur.
Vitamin D has many roles in the body and is essential for optimal health. For example, it instructs the cells in your gut to absorb calcium and phosphorus - two minerals that are essential for maintaining strong and healthy bones.
On the other hand, low vitamin D levels have been linked to serious health consequences, including osteoporosis, cancer, depression and muscle weakness.
In addition, only a handful of foods contain significant amounts of vitamin D. These include cod liver oil, swordfish, salmon, canned tuna, beef liver, egg yolks and sardines. That said, you would need to eat them nearly every day to get enough vitamin D.
If you do not get enough sunlight, it’s often recommended to take a supplement like cod liver oil. One tablespoon (14 grams) of cod liver oil contains more than three times the recommended daily amount of vitamin D. It’s important to note that the sun’s UVB rays cannot penetrate through windows. So people who work next to sunny windows are still prone to vitamin D deficiency.
Expose Your Skin Around Midday
Midday, especially during summer, is the best time to get sunlight. At noon, the sun is at its highest point, and its UVB rays are most intense. That means you need less time in the sun to make sufficient vitamin D. Many studies also show that the body is most efficient at making vitamin D at noon.
For example, in the UK, 13 minutes of midday sunlight exposure during summer three times per week is enough to maintain healthy levels among Caucasian adults. Another study found that 30 minutes of midday summer sun exposure in Oslo, Norway was equivalent to consuming 10,000 - 20,000 IU of vitamin D.
The commonly recommended daily dose of vitamin D is 600 IU (15 mcg).
Not only is getting vitamin D around midday more efficient, but it might also be safer than getting sun later in the day. One study found that afternoon sun exposure may increase the risk of dangerous skin cancers.
Skin Color May Affect Vitamin D Production
The color of your skin is determined by a pigment called melanin. People with darker skin typically have more melanin than people with lighter skin. Melanin helps protect the skin against damage from excess sunlight. It acts as a natural sunscreen and absorbs the sun’s UV rays to defend against sunburn and skin cancers.
However, that creates a big dilemma because darker-skinned people need to spend longer in the sun than lighter-skinned people to produce the same amount of vitamin D. For that reason, if you have dark skin, you may need to spend a bit more time in the sun to get your daily dose of vitamin D.
Does Sunscreen Affect Vitamin D?
People use sunscreen to protect their skin against sunburns and skin cancer. That’s because sunscreen contains chemicals that either reflect, absorb or scatter sunlight. When this happens, the skin is exposed to lower levels of harmful UV rays.
However, because UVB rays are essential for making vitamin D, sunscreen could prevent the skin from producing it. In fact, some studies estimate that sunscreen of SPF 30 or more reduces vitamin D production in the body by about 95-98%.
The advice is to try going without sunscreen for just the first 10-20 minutes, depending on how sensitive your skin is to sunlight, and apply sunscreen before you start burning.
Dangers of Too Much Sunlight
While sunlight is great for vitamin D production, too much can be dangerous, as most people are well aware. Sunburn is the most common, but amongst other effects are premature ageing, skin changes, such as freckles and moles, heat stroke and the most serious being skin cancer.
Experts recommend reapplying sunscreen every two to three hours you spend in the sun, especially if you’re sweating or bathing.
Regular sun exposure is the most natural way to get enough vitamin D.
To maintain healthy blood levels, aim to get 10-30 minutes of midday sunlight, several times per week. People with darker skin may need a little more than this. Your exposure time should depend on how sensitive your skin is to sunlight. Just make sure not to burn.
Factors that can affect your ability to make vitamin D from sunlight include the time of day, your skin color, how far you live from the equator, how much skin you expose to sunlight and whether you’re wearing sunscreen.
For example, people who live farther away from the equator typically need more sunlight because the sun’s UV rays are weaker in these areas. They also need to take vitamin D supplements or eat more vitamin-D-rich foods during the winter months, since they cannot make it from sunlight.
If you’re planning to stay in the sun for a while, it’s best to apply sunscreen after 10–20 minutes of unprotected sun exposure to help prevent sunburn and skin cancer.