A team of researchers, led by Dr. Oscar Franco at Warwick Medical School in the United Kingdom, recruited 3,262 men and women between the ages of 50 and 70 from Beijing and Shanghai as part of the Nutrition and Health of Aging Population in China (NHAPC) project. The goal of their cross-sectional study was to examine the link between vitamin D levels in the blood and the prevalence of metabolic syndrome, which is known to increase the risk of heart disease and diabetes. The researchers interviewed study participants to collect demographic details and information about education background, smoking status, alcohol use and physical activity. Each participant also underwent a physical examination, which included taking weight, height and blood pressure measurements. Participants also self-reported diabetes, high blood pressure, lipid disorders, heart disease, stroke and medication use. The study found that 69.2% were deficient for vitamin D, 24.4% insufficient and 6.4% sufficient.
“As we get older our skin is less efficient at forming vitamin D,” says Dr. Franco, who notes that vitamin D is mainly obtained from exposure to the sun, as well as from certain foods such as oily fish and eggs. And he adds, “Our diet may also become less varied, with a lower natural vitamin D content. Most importantly, the production of vitamin D after a normal amount of exposure to UVB light decreases with age because of skin changes. When we are older, we may need to spend more time outdoors to make sure we get the same levels of vitamin D we had when we were younger.”
So what does Dr. Franco suggest specifically? “We recommend that older people spend between 5 and 30 minutes, twice a week in the sun to have the desired effect.” What about sun damage? He explains that the impact of the additional sunlight is the same whether or not a sunscreen with a factor of 8 or less is used. The results of the study, published in Diabetes Care, are consistent with the findings of other studies in Western populations.
News Release: Sunshine can help you live longer by cutting risk of heart disease and diabetes www.telegraph.co.uk May 18, 2009
News Release: Sunshine the key to long life http://www.nhs.uk/news/2009/05May/Pages/VitaminDSunshineElderly.aspx May 18, 2009
