Antioxidants Lower Risk of Heart Disease, Study Finds
Apr 25th, 2013
Dietary antioxidants, such as beta-carotene and vitamins C and E, are known to aid in the prevention of some cancers. Additionally, dietary antioxidants help protect people from cardiovascular disease.
Peripheral Arterial Disease (PAD) is an important manifestation of systemic atherosclerosis that is characterized by obstruction of the arteries in the lower limbs. Experimental and epidemiological studies suggest a key role for oxidative stress in initiation and progression of the atherosclerotic process.
Peripheral Arterial Disease affects an estimated 10 million Americans and increases the chance of death from a cardiovascular event. Reduced blood flow causes pain in the legs and increases blood pressure in people who have Peripheral Arterial Disease. However, the causes of the disease are unknown.
Low antioxidant levels contribute to increased blood pressure during exercise for people with peripheral arterial disease, according to researchers at Penn State Hershey Heart and Vascular Institute. The researchers posted their findings in the Journal of Physiology and were funded by the National Institutes of Health. Antioxidants help to neutralize free radicals, chemicals continually formed within cells during normal metabolism that can cause inflammation. The association between antioxidant intake and disease was examined primarily by logistic regression.
“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,” said Matthew Muller, lead author of the study, postdoctoral fellow in Larry Sinoway’s lab at Penn State College of Medicine.
The study showed that blood pressure increases more with exercise in more severe Peripheral Arterial Disease cases. By infusing the antioxidant vitamin C into the blood, researchers were able to lessen the increase in blood pressure during exercise. Vitamin C does not lessen the increase in blood pressure of PAD patients to that of healthy people. As the intensity of exercise increases, the effects of vitamin C decrease but are still seen.
A group of five PAD patients and five without PAD had their leg muscles electrically stimulated to remove the brain’s role in raising blood pressure during muscle contraction in this disease. Increased blood pressure during exercise occurs in both legs, before pain begins, and relates to the severity of the disease.
“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,” Muller said. “Therefore, supplementing the diet with antioxidants may help these patients, but more studies are needed to confirm this concept.”
Related posts from our blog:
No related posts.