Vitamin D For Flexible Arteries
Taking vitamin D may help benefit your heart by reducing the rigidity (stiffness) of arterial walls, which is a predictor of cardiovascular disease. This news comes from a study at the Medical College of Georgia enrolling 70 healthy African-Americans ages 13 to 45 who were overweight or obese and vitamin D deficient. Researchers randomized the participants to receive 4,000, 2,000 or 600 IUs of “D” daily or a placebo, and measured how pliant their arteries were. After 16 weeks, arterial stiffness had dropped by 10.4 percent in participants who took 4,000 IUs and by two percent among those who took 2,000 IUs. However, arterial stiffness increased a bit – by 0.1 percent – among those who took 600 IUs and by 2.3 percent in those on the placebo. Study leader Yanbin Dong, a geneticist and cardiologist, noted that overweight or obese blacks are at increased risk for vitamin D deficiency because darker skin absorbs less UV rays from sunlight, limiting the amount of “D” the skin makes. The investigators wrote that arterial stiffness and vitamin D deficiency might contribute to the higher rates of cardiovascular disease among blacks compared to whites. A larger, longer study of those at high risk is planned.
My take? Deficiencies of vitamin D are common, especially in industrialized countries in northern latitudes, where sun exposure is typically infrequent. Low levels of “D” may be indicated by weak muscles, porous bones that fracture easily, various other health problems and, perhaps, as this study suggests, by arterial stiffness. I advise everyone to have their vitamin D levels tested and recommend taking 2,000 IU of vitamin D per day. (No adverse effects have been seen with supplemental intakes up to 10,000 IU of “D” daily.) Look for supplements that provide D3 (cholecalciferol) rather than D2 (ergocalciferol). Anyone with vitamin D deficiencies should discuss intake levels with his or her physician.
Yanbin Dong et al, “Dose responses of vitamin D3 supplementation on arterial stiffness in overweight African Americans with vitamin D deficiency: A placebo controlled randomized trial.” PLOS ONE, December 7, 2017, DOI: 10.1371/journal.pone.0188424
Also in this week’s bulletin: