Dutch scientists form the Wageningen University (The Netherlands) analyzed results from the Zutphen Elderly Study and came to the conclusion that dietary intakes of alpha-carotene and beta-carotene reduce the risk of cardiovascular diseases. The intake of vitamin C or vitamin E had no influence on mortality caused by cardiovascular diseases. The Zutphen Elderly Study followed 559 elderly men for a period of 15 years. The main dietary source of the carotenoids were carrots [1]. Another epidemiological study demonstrated the beneficial effects of beta-carotene on hypertension. This study examined the relationship between serum levels of various antioxidants, including beta-carotene, on blood pressure among wore than 15 thousand men and women who participated in Third National Health and Nutrition Examination Survey. The study showed that a 1 SD increase of serum beta-carotene was linked with 11% lower risk of hypertension. Both alpha-carotene and beta-carotene were inversely and significantly associated with systolic blood pressure [2].
A study by the Taipei Medical University showed that beta-carotene suppressed cholesterol-induced oxidative stress via modulation of antioxidant system and cholesterol metabolism. Shih and coworkers tested the effect of beta-carotene and canthaxanthin on lipid peroxidation and antioxidative enzyme activities in rats fed with diet high in cholesterol and fat. Beta-carotene significantly increased glutathione peroxidase activity in the erythrocytes and increased superoxide dismutase activity in the liver [3].
[1] Buijsse B, Feskens EJ, Kwape L, Kok FJ, Kromhout D. "Both alpha- and beta-carotene, but not tocopherols and vitamin C, are inversely related to 15-year cardiovascular mortality in Dutch elderly men." J Nutr. 2008 Feb;138(2):344-50.
[2] Chen J, He J, Hamm L, Batuman V, Whelton PK. " Serum antioxidant vitamins and blood pressure in the United States population." Hypertension. 2002 Dec;40(6):810-6.
[3] Shih CK, Chang JH, Yang SH, Chou TW, Cheng HH. " beta-Carotene and canthaxanthin alter the pro-oxidation and antioxidation balance in rats fed a high-cholesterol and high-fat diet." Br J Nutr. 2008 Jan;99(1):59-66.
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