The winter months have arrived and I do a lot of patient education regarding Vitamin D. Here are some highlights:

Checking your vitamin D levels every year is crucial to supporting overall health and wellness.
Unfortunately many providers fail to order this test and patients are left wondering what their levels are.
We make vitamin D in our skin from sunlight exposure but this depends on many factors - our skin tone, the time of day and the season. In northern latitudes even if you go outside naked on a sunny day in the winter, it is thought that the sun is too low in the sky and its rays are too weak to produce sufficient vitamin D in your skin.
Going into the winter months is a perfect time to test vitamin D so that we can determine if supplementation is necessary and how much to take.
Vitamin D is an essential nutrient that affects many different systems in the body - the immune system, gut health, bone health as well as mood. Low levels of vitamin D are linked to more severe Seasonal Affective Disorder (SAD).
Many patients are unaware that there is an "optimal level" of vitamin D and even if your numbers are considered "normal," they may not be "optimal."
Vitamin D is a fat-soluble nutrient which means it needs to be taken with food for optimal absorption.
Make sure you are taking the active form of vitamin D which is D3. The inactive form, D2, requires conversion to D3 before the body can use it.
Blood testing for vitamin D is the only way to know for sure if you are deficient or not.
Vitamin D does not require fasting before the blood draw but you should not take a vitamin D supplement before you get your blood drawn.
Vitamin D dosage should be based on your blood work, where you live and how much time you spend outdoors. Make sure you always get an individualized recommendation that takes into account these factors.
Vitamin D is found in food but not in a lot of them and not in high amounts. Vitamin D is found in fortified milk and juice, mushrooms, swordfish, salmon, cod liver oil, beef liver and egg yolks.