Sunshine is the best natural source of D-vitamin but new research points to supplements as a more responsible choice.
Emerging science underpins the need for increasing our levels of D-vitamin as a way of preventing disease but according to a new study, supplements are better than sun for obtaining that boost. Using a computer-simulated model to determine how much sun was needed to produce blood levels of D3-vitamin in the range of 400 or 1,000 IU (10 or 25 micrograms), researchers from the Memorial Sloan-Kettering Cancer Center in New York and the Norwegian Institute for Air Research found that there were considerable variations depending on geography, season, and skin type. This insecurity combined with the fact that increased sun exposure is associated with an increased skin cancer risk led them to conclude that supplements are a safer and more practical solution.
Problems during winter
Writing in the June issue of the Journal of the American Academy of Dermatology, the scientists describe how they chose two geographical sites, Miami (Florida), and Boston (Maine), for their research. Their simulation was done during the months January, April, July, and October.
During summer in Boston, three to eight minutes of UV exposure to about 25% of the body surface would synthesize 400 IU of D-vitamin, whereas it would be difficult to produce any D-vitamin during winter in that area. In Miami, on the other hand, three to six minutes of daily exposure would produce 400 IU of D-vitamin all year round.
Recent studies have revealed that a surprisingly large part of the populations in European countries with climates similar to that of Boston have lower-than-optimal levels of D-vitamin. Considering that daily intake of D-vitamin up to 50 micrograms (2,000 IU) is viewed as safe, a recommendation of D-vitamin supplements rather than increased sun exposure is probably a more prudent strategy.
D-vitamin deficiency is associated with an increased risk of such ailments as sclerosis, osteoporosis, certain cancers, bone fractures, infectious diseases, cardiovascular diseases, and there is even evidence pointing to an increased risk for diabetes.
Journal of the American Academy of Dermatology
June 2010, Volume 62, Issue 6, Pages 929.e1-929.e9
“Estimated equivalency of vitamin D production from natural sun exposure versus oral vitamin D supplementation across seasons at two US latitudes”
Authors: V. Terushkin, A. Bender, E.L. Psaty, O. Engelsen, S.Q. Wang, A.C. Halpern
How to choose the best supplement
There is a huge variety of D-vitamin supplements on the market but it pays off to be selective. D-vitamin is a fat-soluble nutrient and research1 shows that oil-based D-vitamin supplements are absorbed better than supplements based on powder or ethanol.
D-Pearls contains 38 micrograms of D3-vitamin dissolved in cold-pressed olive oil in small, round gelatin capsules (“pearls”) that are easy to swallow – or chew (they have a pleasant taste of fresh olive oil). The product is manufactured by Pharma Nord, one of Europe’s leading manufacturers of high-quality nutritional supplements and natural remedies. D-Pearls complies with GMP standards (Good Manufacturing Practice).
1Molecular Nutrition & Food Research, april 2010.