Known as the “sunshine vitamin,” vitamin D comes to us primarily through the magic of sunlight (when it hits our body, we produce it) and secondarily through our food. Unlike other vitamins, though, we can’t really eat our way to the right vitamin D levels, says the Vitamin D Council—since the foods that contain it (like salmon and milk) provide less than 10 percent of our requirement. Considering 50 percent of the world’s population has a vitamin D deficiency, according to the Journal of Pharmacology and Pharmacotherapeutics, that’s some cause for alarm.
Vitamin D is a major player in our health. Research from the same journal shows that vitamin D can support and protect our immune, heart, and mood health, among other things. In fact, a lack of D can cause all sorts of issues, like something called rickets (the softening and weakening of bones), incidences of which the Mayo Clinic says have dramatically increased since the year 2000. Other issues potentially related to a lack of D include difficulty thinking clearly, bone pain, muscle pain, and fatigue.
So, who’s most at risk for vit D deficiency? Read on and learn.
Vegetarians and Vegans
We already know that small amounts of D come from salmon and milk—so what happens if you’re a vegan or vegetarian who also doesn’t live in a sunny climate?
Those who don’t eat animal products have to be especially careful to bare some skin outside, says nutritionist Isabel K. Smith. But since the sun can be damaging, she recommends a vitamin D supplement.
Interesting to note: “Using sunblock reduces the body’s ability to make active D3 by 90 percent,” says Smith. (D3 is the form of vitamin D that is synthesized (or made) by the skin when exposed to sunlight).
People With Depression
The link between depression and vitamin D is not fully understood, but it is established. In the journal Nutrients, a D deficiency was also associated with an increased risk of depression (by eight to 14 percent) and suicide risk (by 50 percent). If you are depressed or if depression runs in your family, having your serum D levels checked is a safe bet. However, it is prudent to also speak with a licensed therapist.
Related: Shop vitamin D products to boost your health.
Nursing Mothers
Breastfeeding mothers are providing nutritional needs for themselves and their babies, which requires a high level of nutrient intake to keep both mother and child healthy.
Vitamin D levels were found to be low in the overwhelming majority of nursing mothers in a study by PLOS One. Scarily, the study concluded that vitamin D3 supplementation at a dose of 1200 IU/d was somewhat effective at improving vitamin D status of nursing women, but not sufficient enough to fully restore the depletion. While further research needs to be done, it’s clear that nursing moms can benefit from both supplementation and sunshine.
People With Dark Skin
People who have darker skin are more at risk of vitamin D deficiency. That’s because the high concentration of melanin in darker skin significantly slows the creation of D. In fact, the American Society of Nutrition found that African-Americans have the lowest rates of vitamin D among all Americans. If you have darker skin, be sure to use a supplement and not depend on sun exposure alone.
Those with illnesses OR predispositions to certain illnesses
A host of health issues have been potentially linked to vitamin D deficiency. According to a study published in the Journal of American Medicine, Caucasians who are low in vitamin D have a significantly higher risk of developing MS compared to those who have sufficient D levels. This connection was not found to be true with African-Americans or Hispanic people, and further studies are needed.
A study looking at the relation between macular degeneration (loss of eyesight) and vitamin D in the Archives of Ophthalmology found a definite link between low serum D levels and the incidence of this eye disease in women under age 75.
And, if you have an inflammatory bowel disease such as Irritable Bowel Syndrome or Crohn’s, your absorption of vitamin D is probably seriously compromised.
People Who Take Certain Medications
There are a handful of medications that, when taken regularly, can block the body’s ability to absorb vitamin D. Those who take anticonvulsant medications, glucocorticoids, antifungals such as ketoconazole, and medications for AIDS will want to have their vitamin D levels tested for deficiency.
People With Chronic Pain
If your muscles or joints are chronically sore, it’s definitely worth it to request a blood draw to measure your serum vitamin D level. A study in Presse Medical found that people with severe vitamin D deficiency saw an improvement after using high doses of D.
People Who Sit Inside All Day
Let’s face it—this is most of us. Even those who work from home rarely sit in front of a window with the sunshine pouring in. (Doesn’t that sound lovely, though?) According to a Clinical Laboratory study, people who working primarily indoors are basically guaranteed a low vitamin D level, so you may want to consider supplementation.
What Now?
If any of the above applies to you, you’ll want to ask your physician to check your vitamin D levels. That way, if you are deficient in vitamin D, you can plan your sun time and look for a proper supplement dosage.