For some of us, the new normal of working from home may have reduced our time outdoors — and this may mean fewer opportunities to take in the morning sun. This could also mean that we are missing out on one of our bodies’ best sources of vitamin D.

Known as “the sunshine vitamin”, vitamin D is a steroid hormone produced when your skin is exposed to sunlight. Contrary to its name, vitamin D is not really a vitamin, but actually a prohormone — a precursor to a hormone. In essence, vitamins are nutrients that the body cannot synthesize, and thus must be obtained through diet. Our bodies, on the other hand, can produce their own vitamin D.

Nonetheless, sun exposure rarely provides us with the adequate vitamin D our bodies need, so we have to make sure that we also get it from our diet. Let’s take a closer look at this family of compounds that we refer to as vitamin D, and learn why it’s vital to our health.

Why Do We Need Vitamin D?

Vitamin D is needed by our body in order to absorb calcium and stimulate bone formation. In children, too little vitamin D causes rickets, while in adults, not enough vitamin D causes weak, deformed bones (osteomalacia). Vitamin D is also required for a variety of other bodily functions such as:

• promoting healthy teeth
• supporting lung functions
• supporting various body systems (cardiovascular, immunological, nervous) 
• controlling insulin levels and assisting in the management of diabetes

Vitamin D has also been considered beneficial for a healthy pregnancy. According to research, pregnant women who are vitamin D deficient are more likely to develop preeclampsia and give birth prematurely. Low vitamin D levels in pregnant women have also been linked to gestational diabetes and bacterial vaginosis.

Furthermore, vitamin D deficiency has been linked to diseases and maladies such as heart ailments, breast cancer, prostate cancer, colon cancer, depression, and even weight gain. Studies suggest that those with greater vitamin D levels have a decreased risk of disease, but more research is needed to determine whether a deficiency of vitamin D causes disease, or if supplementing with vitamin D reduces these risks.

Sources of Vitamin D

Sunshine is still an effective way to get your daily dose of vitamin D. Keep in mind though, that if you're going to be out in the sun for a lengthy amount of time, you should make sure to wear adequate sunscreen (SPF of at least 30). Although the sun is beneficial to your health, sunburns can cause premature skin aging and increase your risk of skin cancer.

That said, you can also get vitamin D from food sources such as:

• cod liver oil
• fatty fish like salmon, tuna, and mackerel
• beef liver
• egg yolks
• cheese
• fortified milk
• mushrooms
• cereals and juices

Can You Have Too Much Vitamin D?

Long-term intake of excessively high dosages of vitamin D3 may result in an excessive accumulation of the vitamin in your body. When blood levels of vitamin D exceed 150 ng/ml, intoxication ensues. This can lead to elevated blood levels, constipation or diarrhea, bone loss, or even kidney failure. 

Nonetheless, there isn’t much to be worried about, as vitamin D toxicity is quite uncommon. It occurs almost exclusively in patients who take high-dose supplements for lengthy periods of time without duly checking their blood levels.