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Tackling Vitamin D Deficiency

Tackling Vitamin D Deficiency

If you live in the northern half of the United States, the air is getting cooler, the leaves have fallen from the trees and the birds have headed south. Winter is fast upon us, and with that comes shorter days and longer nights.

You—or someone you know—may be noticing that during these shorter, darker days you’re feeling symptoms of depression, less energetic and more irritable. No, you’re not going crazy. What may be happening is that you’re experiencing the lack of a rather underappreciated vitamin: Vitamin D.

Vitamin D, created by the body when UVB rays from the sun come in contact with the skin, is best known for being responsible for helping the body absorb calcium, and in this way it helps to strengthen bones. Vitamin D is also partially responsible for control of genes related to different cancers, autoimmune diseases and infection.

And although research is still being developed around the link between depression and Vitamin D, researchers have pinpointed a correlation between people who are battling depression and lower-than-normal levels of Vitamin D in their blood. Conversely, people who have higher levels of Vitamin D in their blood have a lower risk of becoming depressive.

Location Matters

If you live above the 37th parallel (37 degrees latitude) anywhere in the world, you are at an increased risk for Vitamin D deficiency between the months of September and May. During these months, the angle of the sun does not allow for our bodies to synthesize Vitamin D from UVB, and at the peak of winter we are lucky if we get 10 hours of daylight per day. This combination leads some individuals to suffer from Seasonal Affective Disorder (SAD). SAD can cause irritability, tiredness, anxiety, depression, poor appetite, weight loss and excessive sleepiness, to name a few symptoms.

Food Matters

So now you’re probably saying to yourself, “Well, Nat, I can’t move south every winter like the birds, so what should I do to reduce my risk of Vitamin D deficiency?” Well, you’re in luck!

Preventing Vitamin D deficiency—and the negative health aspects associated with it—can be easy. A study published in Harvard Women’s Health Watch has shown that by taking 1100 IUs of Vitamin D and 1400-1500 mg of calcium per day, you can reduce your risk of Vitamin D deficiency and other diseases by up to 77% after four years.

One way to get your recommended Vitamin D is from a pill supplement. Or, that same Harvard study points us to certain foods that are high in Vitamin D, such as:

  • Salmon (3.5 oz.) = 360 IU
  • Mackerel (3.5 oz.) = 345 IU
  • Tuna (3.5 oz., canned) = 200 IU
  • Orange juice (8 oz., fortified) = 100 IU
  • Milk (8 oz., fortified) = 98 IU
  • Breakfast cereal (1 serving, fortified) = 40-100 IU

Source: Office of Dietary Supplements, National Institutes of Health

Eating foods that are high in Vitamin D and combining them with supplemental Vitamin D and calcium can make all the difference in your mood during these months.

It is important that you pay attention to how you are feeling as the seasons change, and if you are noticing that you are feeling sleepy, slower, sad, or just plain lousy this winter, and if you’re north of the 37th parallel, you might just be suffering from Vitamin D deficiency. Now you know what to do.

If you have any questions, contact your primary care doctor.

Nat Williams, a Resource Health Navigator for ImagineCare, earned a degree in Wellness and Alternative Medicine from Johnson State College in Vermont. As a wellness coach, he loves to be able to have one-on-one conversations with people about their health, and is passionate about finding new ways to empower them to take control of their own health. Outside of ImagineCare, you’ll find Nat outdoors, going for a hike, riding his mountain bike, camping, or just lying in his hammock. 


This article originally appeared in the ImagineCare blog.