Higher Vitamin D Levels Linked To Lower Hypertension Risk

Higher vitamin D levels linked to lower hypertension risk

Higher vitamin D levels strongly associated with reduced death from all causes over nearly a decade

Tuesday, March 12, 2013. The results of a meta-analysis that appeared this month in the European Journal of Epidemiology reveal an association between higher vitamin D levels and a lower risk of developing high blood pressure.

S. K. Kunutsor of the University of Cambridge and colleagues selected eight articles describing eleven studies for their analysis. Seven studies reported vitamin D status as serum or plasma 25-hydroxyvitamin D, and four reported vitamin D intake from diet. Study participants were followed for periods ranging from 1.3 to 14 years.

Out of a total of 283,537 subjects, 55,816 cases of hypertension occurred over follow-up. Having a 25-hydroxyvitamin D level among the top one-third of participants was associated with a 30% lower risk of hypertension in comparison with the risk experienced by those whose levels were among the lowest third. A pooled analysis of five studies revealed that each 10 nanogram per milliliter (ng/mL) increase in 25-hydroxyvitamin D was associated with a 12% reduction in the risk of future hypertension.

No significant effect for vitamin D was observed in studies that assessed vitamin D status using intake from dietary sources. Due to the fact that sun exposure can be a major source of vitamin D, the authors remark that dietary intake may not be an accurate indicator of an individual's vitamin D status.

Possible mechanisms cited by the authors to explain the effects of reduced vitamin D levels on blood pressure include activation of the renin-angiotensin-aldosterone system and increased insulin resistance, as well as adverse effects in vascular endothelial and smooth muscle cells.

"This is the largest meta-analysis of prospective associations ever conducted to date which involves more incident hypertension cases than ever before and provides precise estimates of the magnitude of the association of hypertension risk with vitamin D levels," the authors write.

"Studies are needed to determine whether this represents a causal association and also to determine whether vitamin D supplementation or therapy may be beneficial in the prevention or the treatment of hypertension," they conclude.

Reduced antioxidant levels in PAD involved in increased lower extremity blood pressure during exercise

An article published on September 24, 2012 in the Journal of Physiology reveals a protective role for antioxidants, particularly vitamin C, against the rise in blood pressure that occurs in the legs of individuals with peripheral arterial disease (PAD) during exercise. Peripheral artery disease is characterized by poor blood flow and pain in the lower extremities due to the presence of plaque (atherosclerosis).

Lawrence Sinoway and his colleagues at Penn State Hershey Heart and Vascular Institute compared the effects of exercise in subjects with and without PAD. They found an increase in blood pressure in the legs of PAD patients compared to those without the disease. Preadministration of high dose intravenous ascorbic acid reduced this effect in PAD patients by 50 percent. In another experiment in which subjects with and without PAD had their leg muscles electrically stimulated, increases in blood pressure were greater in those with PAD, indicating that the response came directly from the muscle, rather than from the brain.

"Past studies have shown that having low antioxidant levels and increased reactive oxygen species -- chemical products that bind to body cells and cause damage -- is related to more severe PAD," commented lead author Matthew Muller, who is postdoctoral fellow in Dr Sinoway's lab. "This study shows that blood pressure increases more with exercise in more severe PAD cases. By infusing the antioxidant vitamin C into the blood, we were able to lessen the increase in blood pressure during exercise."

"This indicates that during normal, everyday activities such as walking, an impaired antioxidant system -- as well as other factors -- plays a role in the increased blood pressure response to exercise," he added. "Therefore, supplementing the diet with antioxidants may help these patients, but more studies are needed to confirm this concept."

Life Extension Blog

Life Extension's Blog features timely articles by Michael A. Smith, MD and other authors who provide practical tips for better health. Current articles discuss the controversy surrounding the increased presence of vegetable oil in the American diet, reveal a supplement for better looking legs, and inform readers why they should kick their sugar habit for good.

And don't miss this special report: "What do you do if you're getting forgetful."

Let's face it - forgetful moments are in store for anyone who lives long enough. Fortunately, by supporting your brain health and neurological function with the right nutrients now, you can help minimize the cognitive issues that will arise later.

Subscribe to Life Extension's blog at http://feeds.feedburner.com/LifeExtensionBlog or visit online at http://blog.lifeextension.com/

Latest Supplements

Power Foods for the Brain, by Neal D. Barnard, MD
Item #33855

Power Foods for the Brain, a new book by noted nutrition researcher and New York Times best-selling author Neal Barnard, MD, reveals how simple diet changes can shield the brain from memory loss, stroke, and Alzheimer's.

Power Foods for the Brain presents the latest and most compelling research on nutrition's surprising effects on the brain. Dr Barnard also lays out his simple three-step plan to protect the mind and strengthen the memory: put power foods to work, strengthen your brain, and defeat memory threats.

Neal Barnard, MD is an Adjunct Associate Professor of Medicine at the George Washington University School of Medicine and Health Sciences, a Life Member of the American Medical Association, and a member of the American Diabetes Association.

Bioactive Milk Peptides, 30 capsules
Item #01512

Bioactive Milk Peptides (Lactium®) are a cutting-edge nutrient complex consisting of patented bioactive peptides found naturally in milk. Used widely in Europe to promote sustained and restful sleep patterns, published studies reveal that these bioactive milk peptides also promote relaxation, help with stress, and support daytime cognition. A group of 63 women reporting a variety of sleep-related difficulties experienced as much as 65.6% improvement in their symptoms with just 150 mg per day of these bioactive milk peptides. In another study, the same 150 mg dose induced substantial improvements across 27 markers of sleep quality and stress response in 165 healthy adults. And in a third study, a group of healthy men and women taking 150 mg per day of these bioactive milk peptides for one month experienced a 50% improvement in sleep quality after two weeks and needed 30% less time to fall asleep after 4 weeks.

Highlight

Life Extension Update		What's Hot
	Reduced vitamin D levels could help explain high blood pressure in African Americans		Prediabetes and prehypertension associated with reduced vitamin D levels
	Reduced premenopausal vitamin D levels predict hypertension later in life		Pregnant women deficient in vitamin D risk preeclampsia
	Vitamin D deficiency: emerging cardiovascular disease risk factor		Greater vitamin D levels associated with protection from cardiovascular risk factors

Life Extension Magazine®		Health Topics
	Startling findings about vitamin D levels in Life Extension® members		High blood pressure
	Brittle bones and hardened arteries: the hidden link		Atherosclerosis and cardiovascular disease
	Vitamin D's crucial role in cardiovascular protection