You Need More Vitamin D in the Winter – Here’s Why

 

The risk of infections and vitamin D deficiency is increasing as winter approaches. Vitamin D is necessary for good health and can be found in oily fish (mackerel, tuna, and sardines), mushrooms, fortified dairy and nondairy substitutes, and the skin's own production of vitamin D after exposure to sunlight. People need vitamin D to stay healthy and to battle contamination. Ironically, most of us don't get enough vitamin D during the winter, when we need it most. What amount should we take, then? Do we need to take supplements? How can we acquire more? What's more, who needs it most?

Where to get your vitamin D

Since sun exposure causes the skin to produce vitamin D, it is known as the "sunshine vitamin". Similar U V B beams that cause a sun-related burn also make vitamin D. Sunscreen, more obscure skin pigmentation, clothing, and diminished light in winter lessen the skin's capacity to make vitamin D. Individuals who experience the greatest occasional swings in vitamin D levels are lighter-looking people living in the northern locales of the US, as well as at higher latitudes all over the planet, where there is almost no sunlight in winter.

But people of color and those who live in higher latitudes are the most likely to have low vitamin D levels. Because darker skin prevents U V B rays from producing vitamin D, people with dark skin are more likely than people with fair skin to have low levels of vitamin D throughout the year.  However, even people with dark skin have lower levels of vitamin D during the winter. 

Adults who have dark skin or avoid sunlight should consume more vitamin D throughout the year in addition to eating foods high in vitamin D during the winter

Vitamin D is important for bones and your microbes

Doctors initially believed that vitamin D was only necessary for bone health. In the 1980s, researchers discovered that immune cells had receptors for vitamin D. My group's research has shown that vitamin D plays an important role in maintaining health in the gastrointestinal tract. This was because vitamin D deficiency caused bone diseases like rickets in children and osteoporosis in adults. Animals and humans with higher vitamin D levels are less likely to develop inflammatory bowel disease, Crohn's disease, and infections of the gut and lungs.

The study discovered that one function of vitamin D is to maintain the health and happiness of the gut microbes. The gut is home to a greater variety and number of microbes thanks to vitamin D, which together reduce inflammation throughout the body. 

Low vitamin D levels are related to gastrointestinal illness in people. Inflammatory bowel disease patients in Japan exhibit more symptoms in the winter than in other seasons, according to researchers

Why is vitamin D more important in winter?

People spend less time outside and are more susceptible to infections in the winter. Debatable is the exact amount of vitamin D that healthy adults should consume.

Because people are less able to make vitamin D when they go outside in the winter, taking at least 600 IU of vitamin D per day from food or supplements would help keep vitamin D levels at the same level they were in the summer.

However, as with many other things, a vitamin D overdose can be harmful. Vitamin D toxicity is not caused by eating too much or getting too much sun. Vitamin D supplements are recommended by dermatologists and other medical professionals rather than unprotected sun exposure due to the risk of skin cancer.  However, taking too much vitamin D can cause toxicity.

Calcium can be absorbed from food through vitamin D, but too much vitamin D can raise calcium levels in the blood, which can cause kidney disease.

Your gut microbes will be healthier, and you will be more resistant to infection and inflammation throughout the year if you consume more vitamin D during the winter