How to offset seasonal lack of vitamin D on winter solstice and beyond
Dec 21, 2021, 1:44 PM
People spend the afternoon in Cal Anderson Park on June 10, 2021 in Seattle, Washington. (File photo by David Ryder/Getty Images)
(File photo by David Ryder/Getty Images)
Tuesday, Dec. 21, marks the winter solstice in 2021 for the Northern Hemisphere, which means longer days are ahead, and more minutes of daylight. During winter, however, those in the Pacific Northwest lack access to sunlight — as we perhaps know all too well — which means vitamin D production commonly dips too.
Chance Seattle area sees at least 4 inches of snow over Christmas weekend
Morgan Chojnacki, UW Medicine diet and nutrition specialist, explains that the sun’s ultraviolet rays interact with our skin to create vitamin D. This process is how people mostly generate their supply of the vitamin, a benefit of which is to strengthen our bones. In winter months, the sun’s rays are too weak to trigger this process above the 37th parallel north, which is where all of Washington lies.
“A billion people worldwide are vitamin D deficient, including 40% of American adults,” Chojnacki said in a written release from UW Medicine Newsroom. “We can go stand on top of Mount Rainier and get sunburned right now, and we still wouldn’t be able to produce vitamin D.”
While it can be tough to get enough vitamin D from our diet alone, certain fish — like salmon, herring, or tuna — as well as fortified milk and dairy products, fortified soy products, and eggs can help balance the winter deficit. Chojnacki recommends speaking with your doctor before taking a supplement.
Common symptoms of a vitamin D deficiency include muscle weakness and bone pain. Advanced symptoms can include depression, hair loss, and slow-healing wounds.
