Vitamin D Deficiency in the Winter: Health Effects & Supplementation

Disclaimer: Results are not guaranteed*** and may vary from person to person***.

vitamin D deficiencyIf you’ve been enduring a cold, dark, snowy winter that’s keeping you indoors…hold on because the end is in sight! Long winters are not great for your health.

People tend to be more sedentary, experience more frequent depression, and, without knowing it, get far less of vitamin D, a crucial nutrient for the body…leading to vitamin D deficiency.

In fact, vitamin D levels play a role in how you feel once the days get shorter and darker and temperatures drop.

Sources of Vitamin D

Although you can get vitamin D from salmon and fortified items like cereal, yogurt, and juice, the best source of this essential vitamin is sunlight. The more sun exposure you get, the higher your blood levels of vitamin D will be.

Typical recommendations are to get 20 to 60 minutes of direct sun exposure on the face, arms, and legs (the length of time depends on your skin color) per day to achieve adequate vitamin D levels. If you live in a winter climate like me, there’s no way that’s happening.

Vitamin D Deficiency & Winter Climate

So as you may imagine, vitamin D deficiency is more common in certain climates; i.e. those areas that experience much less sunlight and the cold temperatures and snow that keep people indoors in the winter months.

This can be dangerous to your health in a number of ways, as vitamin D deficiency is associated with a host of health problems, including heart disease, cognitive impairment, multiple sclerosis, cancer, muscle pain, bone loss, weight gain, chronic fatigue, and loss of strength.

Vitamin D Supplements: What’s Safe

To combat vitamin D deficiency and related health issues, supplementation is often recommended. But because vitamin D is a fat-soluble vitamin, toxicity is a risk. Therefore, making sure you don’t go overboard with daily supplemental intake is essential to maintaining health. Typically, daily dosages from 600 to 4,000 IU are safe, with dosages dependent on individual cases. Going over 4,000 IU per day can lead to toxic symptoms and illness.

Of course, if you’ve been prescribed a high dose by your doctor, follow their advice (but talk to them about any potential vitamin D side effects).

To learn whether you have enough vitamin D in your blood, a blood test is required. A doctor determines adequate dosing at that point, so it’s recommended that you don’t start popping vitamin D pills before establishing your needs.


Jacobsen, M., “Vitamin D Deficiency,” WebMD web site, May 22, 2016;, last accessed February 17, 2017.