Vitamin D
Vitamin D is a fat-soluble vitamin and is stored in the body’s fatty tissue. Vitamin D helps the body absorb calcium. Calcium and phosphate are two minerals that are essential for normal bone formation. Throughout childhood, the body uses these minerals to produce bones. If you do not get enough calcium, or if your body does not absorb enough calcium from your diet, bone production and bone tissues may suffer. As very few foods naturally contain vitamin D, many foods are fortified with vitamin D. Dietary sources of vitamin D include:
- Cheese
- Butter
- Cream
- Fortified milk
- Fatty fish (such as tuna, salmon, and mackerel)
- Oysters
- Fortified breakfast cereals, margarine, and soy milk (check the Nutrition Fact Panel on the food label)
As it can be very hard to get enough vitamin D from food sources alone, some people may need to take a vitamin D supplement (Medline Plus, 2012).
According to Pearce (2010) in the British Medical Journal:
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Vitamin D insufficiency is common in the UK ;
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Vitamin D deficiency typically presents with bony deformity (known as “rickets”) or hypocalcaemia in infancy and childhood, and with musculoskeletal pain and weakness in adults;
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Vitamin D insufficiency has recently been associated with many other health problems including cardiovascular disease, type 2 diabetes, several cancers, and autoimmune conditions; and
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Risk factors leading to low vitamin D levels include skin pigmentation, use of sunscreen or concealing clothing, being elderly or institutionalised, obesity, malabsorption, renal and liver disease, and anticonvulsant use.
As discussed on the Medline Plus website, the body makes vitamin D when the skin is directly exposed to the sun, which explains why it is often called the “sunshine” vitamin. Most people attain at least some of their vitamin D needs this way. People who do not live in sunny places may not make enough vitamin D. Skin that is exposed to sunshine indoors through a window will not produce vitamin D. Cloudy days, shade, and having dark-colored skin also cut down on the amount of vitamin D the skin makes.
Importantly, the skin makes little if any vitamin D from the sun at latitudes above 37 degrees north or below 37 degrees south of the equator except during the summer months. People who live in these areas are at relatively greater risk for vitamin D deficiency (Harvard Women’s Health Watch, 2008).
Due to its country’s high latitude, the Canadian Cancer Society recommended in 2007 a specific amount of Vitamin D supplementation for Canadians to consider taking, based on the growing body of evidence about the link between Vitamin D and reducing risk for colorectal, breast and prostate cancers (Canada Cancer Society, 2007).
In consultation with their own healthcare provider, the Society recommended that:
- Adults living in Canada should consider taking Vitamin D supplementation of 1,000 international units (IU) a day during the fall and winter; and
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Adults at higher risk of having lower Vitamin D levels should consider taking Vitamin D supplementation of 1,000 IU/day all year round. This includes people: who are older; with dark skin; who don’t go outside often, and who wear clothing that covers most of their skin.
Thus, as Britain lies between 50 and 60 degrees North in latitude, the above information would suggest that vitamin D supplementation is advisable. The brand of vitamin D that I prefer is called “Nature’s Plus” and it can be purchased in adult or child dosages. It can be bought at local health food shops or online.
References
Canada Cancer Society (2007) Canadian Cancer Society Announces Vitamin D Recommendation. http://www.cancer.ca/canada-wide/about%20us/media%20centre/cw-media%20releases/cw-2007/canadian%20cancer%20society%20announces%20vitamin%20d%20recommendation.aspx Accessed 9th January 2012
Havard Women’s Health Watch (2008) Time for more vitamin D http://www.health.harvard.edu/newsweek/time-for-more-vitamin-d.htm Accessed 9th January 2012
Medline Plus (2012) Vitamin D. http://www.nlm.nih.gov/medlineplus/ency/article/002405.htm. Accessed 9th January 2012
Pearce, SHS (2010) Diagnosis and management of vitamin D deficiency. BMJ 2010, 340, b5664
