Even though these warmer temperatures have us feeling like it’s still summer outside, fall is officially here, and unfortunately, that means less daylight hours and colder temperatures. It also means less vitamin D.
Vitamin D is a fat-soluble vitamin essential to human life. While vitamin D is found in fish (such as salmon and tuna), eggs, and fortified dairy products, our primary natural source of the nutrient is through sun exposure. As winter approaches, we spend less time outside and are exposed to less sunlight, decreasing our ability to obtain natural vitamin D.
While most people are not deficient in vitamin D levels, many do not have an optimal level, especially during winter months when UV light and sun exposure is low. Since vitamin D is essential to calcium absorption, low levels can contribute to a loss of bone density, and lead to osteoporosis, osteomalacia (softening of bones), or increased fractures.
And vitamin D may also have some added health benefits. Supplementation has been shown to reduce pain in patients with chronic pain conditions, and also significantly reduces the risk of falls in the elderly. It has anti-inflammatory effects, may help improve immune system function and brain health, and could reduce the risk of cardiovascular disease.
Currently, the recommended daily dose of vitamin D for adults is listed as 600IU, with the upper limit being 4000IU. A study conducted in 2004 found that between 74-96% of Canadians had inadequate vitamin D intake from food sources, and thus Health Canada currently recommends that people over 50 years of age take a daily vitamin D supplement of 400 IU.
However, like any supplement, there is always a risk of taking too much. Excess vitamin D can be damaging to your kidneys, can cause too much calcium to be deposited in the body, or can cause nausea, constipation, or poor appetite.
If you’re concerned about your vitamin D levels as winter approaches, consider increasing your intake of foods high vitamin D, or using a vitamin D supplement. But be sure check with your healthcare provider before starting any new supplement, as your individual health concerns may impact these recommendations.