05 Jun THE ‘D’ DILEMMA
Conflicting media reports on vitamin D are constantly being published, fuelling widespread confusion. Some insist that vitamin D supplementation is vital, others say that the benefits of D are over-hyped. The latter opinion is, however, being debunked by increasing evidence of the link between vitamin D deficiency and numerous health conditions, from immune system insufficiency and fibromyalgia to cancer, depression, TB and heart disease.
A recent article published in ABC7Chicago.com detailed a study that looked at 73 observational studies with almost 850 000 participants, as well as 22 randomised, controlled trials with more than 30 000 participants using vitamin D alone versus placebo or no treatment. The researchers found that in the observational studies the risk of death from cardiovascular disease, cancer and other causes was significantly higher for those who did not take vitamin D supplements.
Can we get all the Vitamin D we need from sunlight?
Vitamin D is also known as the ‘sunshine vitamin’ because it is synthesised from cholesterol in the body with the assistance of sunlight. The D-supplementation detractors will, therefore, insist that we can get enough Vitamin D from exposure to sunlight. Not likely: most people spend the working week indoors, even in sunny climates. If they do get into the sun on weekends, they slather their bodies in sunblock to protect against skin cancer. Even those who spend a lot of time in the sun can be D deficient.
Recently, a KZN south coast builder who spends most of his days in the sun was found to be severely lacking in Vitamin D and was prescribed supplements by his GP. For those living in northern climes access to sunlight is limited, making D deficiency a major problem – so much that it is now considered a global pandemic.
Research determines oral supplementation of Vitamin D to be safest option
In 2010 the Journal of the American Academy of Dermatology published results of a computer simulation model which revealed that it is more beneficial to derive vitamin D from supplements than sun-exposure. Scientists from the Memorial Sloan-Kettering Cancer Centre in New York and the Norwegian Institute for Air Research in Tromsø used a computer model to determine optimal sun exposure times to produce blood levels of vitamin D3 equivalent to 400 or 1 000 IU of vitamin D.
Although the results showed that during summer people would only need exposure to about 25 percent of the body surface for a few minutes to synthesise 400 IU of vitamin D, the researchers said that cutaneous vitamin D synthesis is an intricate process and depends on many variables. They also said that the estimates were rough, as there were many limitations to the models.
They therefore concluded that, “Because of these practical difficulties combined with the detrimental side-effects of UV exposure, we endorse the IARC assessment that even if it is ultimately demonstrated that increasing vitamin D levels impacts on cancer and chronic disease, oral supplements of vitamin D would probably represent the safest way to increase vitamin D status.”
Vitamin D supplementation is also endorsed by the reputable, US-based Council for Responsible Nutrition. Its Vice President, Scientific and Regulatory Affairs, Duffy MacKay, states: “Vitamin D is an essential nutrient for good health and if you’re one of the many people who have low levels of vitamin D, supplementation is a safe and beneficial way to achieve healthy levels.
The current ‘Dietary Guidelines for Americans’ identify vitamin D as one of four nutrients of public health concern because consumers are falling short. Both doctors and consumers should take this into consideration and ensure vitamin D levels are tested during medical checkups. Vitamin D is not easily obtained through food, and getting it through sunlight can pose risks, making supplementation a viable option.”