Are You Getting Enough Vitamin D??

The warm weather is finally here, and it’s time to get outside and enjoy the sunshine!

As you probably know, Vitamin D is an essential nutrient we produce when exposed to the sun. We can also obtain some through diet (primarily fatty fish), however few cultures consume an adequate quantity to meet their needs. Despite sunshine, dietary sources, and even supplementation, 25% of Canadians have sub-optimal levels in summer, increasing to 40% in the winter!

Vitamin D is so important because it plays a huge role in gene control and cell functioning. Low levels have been linked to many diseases, including osteoporosis, diabetes, multiple sclerosis, cardiovascular disease, impaired immune function, rickets in children, and several cancers.

Here is what you need to know to maximize your levels!

1 – Ultraviolet (UV) Rays

Sunlight is composed of about 1500 wavelengths, but the only one that will have you produce Vitamin D is UVB. These rays induce Vitamin D production at a rate of up to 1000 IU per minute! Once maximum production is reached (within about 20 minutes at midday, in summer, for a fair-skinned individual) additional units are destroyed to avoid toxicity.

2 – Exposure

Vitamin D is only produced when UVB-rays shine directly on exposed, non-protected skin. Sunscreen will greatly impact production, as will clothes, clouds, pollution, and windows. Limit yourself to the 20 minutes per day as stated above (or longer if dark-skinned) to optimize production without high risk of sun damage.

3 – Time of Year

UVB-rays are short and therefore can only penetrate the atmosphere when the sun is high and strong enough. For most of Canada, this means we are likely not producing enough Vitamin D a whole 6 months out of the year! Fortunately, excess amounts are stored in the body, therefore daily exposure in the summer can help you get through the winter.

4 – Time of Day

For the same reason as above, UVB-rays can only penetrate for a limited time each day (assuming the sun is strong enough and there is no interference). The time varies depending on date and geographic location, but generally 11am – 3pm during the summer is a useful reference.

 5 – Absorption

Vitamin D is produced on the surface layers of the skin and then absorbed into the body. Refrain from washing your arms and legs with soap during the first 48 hours of sun exposure to maximize absorption.

6 – Diet and Supplements

Without testing, it is impossible to determine whether you have sufficient levels of Vitamin D, especially during the winter months. Age, skin pigmentation, and environmental factors are all conditions which can impact production. A dietary supplement (look for Vitamin D3) and food sources in addition to sunshine are all viable options.