Getting those sunny, bone health vitamins

Joke: Why can’t you trust your daughter when it comes to your bone health? ... Because vitamin D comes from the sun ☀️.

The body has the ability to produce vitamin D and vitamin K. So why, as Canadians, do we need additional vitamin D in our diet or supplementation? In the late fall, winter, and early spring months, Canadians and those in the northern regions lack the adequate amount of ultraviolet (UV) exposure to produce enough vitamin D. For those who live close to the equator, vitamin D levels are not a big deal because the sun’s frequency is more intense all year round. The frequency of the sun’s rays gives a higher or lower UV index value. This index gives us an estimate of how long it will take to burn when exposed to sunlight.

On the sunshine index, a value of 3 or more allows the keratinocytes in the skin to produce and metabolize vitamin D. Due to the Canadian climate and geography, a UV index of 3 or more is only available through the late spring to early fall and generally is highest between the hours of 10 a.m. to 2 p.m. (1). For this reason, it is important to get vitamin D in the diet and as a supplement. Vitamin D is most known for being found in fish oils but is also high in liver, fortified dairy, and egg yolks. For the majority of people, a typical diet will not give enough vitamin D to meet their recommended daily intake. Therefore, supplementing is essential in the darker months of the year. Adults should have a daily intake of 2500 IU (international units) of vitamin D (1). Studies show that children between the age of 1 to 18 need between 600 and 1000 IU daily (1). Vitamin D can become toxic in the body because it is not excreted through the urine. Fat soluble vitamins, such as: D, A, K, and E, are stored in the fat tissue and are excreted slowly.

What does vitamin D do anyway, you may ask? It has a direct relationship with calcium and phosphorus absorption for good bone health (2). It also keeps muscles functioning well which reduces the risk of falls, and thus fractures. For children, a lack of vitamin D can cause rickets which is a bone softening disease (2). Soft bones can lead to deformation as the bones can bend while the child is still growing. This is most notable in the femurs (thigh bones) and can cause 'knocking knees' or a waddle-like gait. Adults' bones are fully developed, but a lack of vitamin D and calcium absorption can also lead to bone softening. This is called osteomalacia. Over time, someone with soft bones will have reduced inner bone strength/density and their osteomalacia can progress to osteoporosis (1,2). Those with osteoporosis have more brittle bones and have much higher risk of fracture for trauma or falls.

If you are uncertain about vitamin D or fear that you are supplementing with too much vitamin D, speak with your chiropractor, family doc, naturopath, or pharmacist.

Stay fortified and sunny,

Dr. Cole Maranger, DC

If you want more details, check out:

1. Vitamin D Fact Sheet. Multiple Sclerosis Society of Canada. PDF. Retrieved from: https://mssociety.ca/library/document/38cuveX9sSrF0QEZ1DfOMUaBilKTyRJk/original.pdf

2. Leanne et al. Vitamin D–deficiency rickets among children in Canada. Canadian Medical Association Journal. PDF. Retrieved from: https://www.cmaj.ca/content/cmaj/177/2/161.full.pdf

3. Vitamin D. Harvard T.H. Chan. The nutrition source. Web. Retrieved from: https://www.hsph.harvard.edu/nutritionsource/vitamin-d/