Against the Wall High: Blood Pressure

Continued from Yesterday

Calcium absorption requires sufficient vitamin D, another essential nutrient with some ties to blood pressure. An inverse relationship between plasma 25-hydroxyvitamin D levels and risk of incident hypertension in young women was reported in a late 2008 study from Harvard Medical School researchers, who noted young women with low levels of vitamin D had a substantially higher risk of hypertension than women with sufficient levels of the vitamin.14 In 2011, a report from the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University, Boston, concluded while clinical evidence is lacking, observational data suggests “vitamin D supplementation could potentially have a strong preventive effect on some of these conditions and could reduce race-related disparities in their prevalence.”15

Two other essential vitamins are possibly involved in blood pressure. Vitamin C, which contributes to collagen production and vascular flexibility, may affect blood pressure by targeting increased oxidative stress associated with the condition.16 Japanese researchers found 600 mg/d ascorbic acid significantly reduced systolic and pulse pressure in elderly patients being treated for hypertension.17 And 1,000 mg/d of vitamin C added to antihypertensive therapy reduced systolic blood pressure and decreased oxidative stress in an Indian trial.18

Vitamin C taken along with vitamin E affects blood pressure and several related parameters. A University of Pisa, Italy, trial showed hypertensive men taking vitamin C (1 g/d) and vitamin E (400 IU/d) for eight weeks experienced significantly improved flow-mediated dilation (FMD) and arterial flexibility, as well as vasodilation and oxidative stress parameters.19 Similar research found hypertensive men taking vitamins C and E for eight weeks had significantly lower systolic and diastolic blood pressure, in addition to higher serum antioxidant capacity.20

A closer look at vitamin E reveals the effects of specific fractions on blood pressure. Early work from a Malaysian research team found as much as 320 mg/d of tocotrienol-rich vitamin E (TRE) was well-tolerated and increased plasma concentrations of alpha-, delta- and gamma-tocotrienol, but did not significantly affect arterial compliance, plasma total antioxidant status or LDL cholesterol levels in normal subjects.21 However, their subsequent research revealed a self-emulsifying TRE preparation in varying dosages (50 mg/d, 100 mg/d and 200 mg/d for two months) generated a trend toward arterial compliance.22 Further, results from Texas Southern University, Houston, research team indicated supplementation with gamma-tocotrienol may enhance total antioxidant status, reduce lipid peroxidation in plasma and blood vessels and inhibit blood pressure increases.23 Their follow-up work detailed how gamma-tocotrienol may improve blood pressure by increasing nitric oxide synthase (NOS) activity, which is reduced in hypertension.24

Continued Tomorrow

http://www.naturalproductsinsider.com/articles/2011/04/against-the-wall-high-blood-pressure.aspx

http://www.depsyl.com/

http://back2basicnutrition.com/

http://bionutritionalresearch.olhblogspace.com/