The Sunshine Vitamin
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: poor immune health, osteoporosis, cancer, depression and muscle weakness. In addition, only a handful of foods contain significant amounts of vitamin D.
25% of Canadians are Vitamin D deficient in the summer!
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. 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.
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.