Close on the heels of the publication of a study in the AMA journal Archives of Neurology linking the consumption of a Mediterranean diet to a lower risk of mild cognitive impairment and Alzheimer's disease, an article published online on February 17, 2009 in the American Heart Association journal Circulation reports an association between greater adherence to a Mediterranean diet and a reduction in deaths from coronary heart disease and stroke in women.
Teresa T. Fung of Simmons College in Boston along with colleagues at Harvard University and Brigham and Women's Hospital evaluated data from 74,886 participants in the Nurses' Health Study for the current analysis. Dietary questionnaires administered six times during the follow-up period were scored for adherence to the Mediterranean diet, which is characterized by a high intake of vegetables, fruits, nuts, whole grains, legumes, fish, and monounsaturated fat, a low intake of saturated fat, red and processed meats, and moderate alcohol consumption (between 5 and 15 grams per day).
Over two decades of follow-up, 1,597 nonfatal and 794 fatal cases of coronary heart disease, and 1,480 nonfatal and 283 fatal strokes occurred. Women whose Mediterranean diet scores were in the top 20 percent of participants had a 29 percent lower adjusted risk of coronary heart disease, a 42 percent lower risk of fatal heart disease, a 13 percent lower risk of stroke, and a 31 percent lower risk of fatal stroke compared to women whose scores were among the lowest fifth. Combined coronary heart disease and stroke risk was lowered by 22 percent, and the risk of cardiovascular fatality by 39 percent, for those whose diet scores were in the top 20 percent.
Consumption of a Mediterranean diet has been associated with reductions in inflammatory markers (such as C-reactive protein), lipids and blood pressure, all of which increase cardiovascular disease risk when elevated. The beneficial effect of the diet on the vascular system may also explain the reduced risk of mild cognitive impairment observed in the Archives of Neurology study. The higher fish intake that characterizes the diet could explain, in part, the lower risk of fatal coronary heart disease events observed in the current study, since greater fish intake has been linked with a lower risk of death from heart disease.
"Greater adherence to the Mediterranean diet, as reflected by a higher Alternate Mediterranean Diet Score, was associated with a lower risk of incident coronary heart disease and stroke in women," the authors conclude. "Because this analysis is conducted in women and because it is the first report on the effects of Mediterranean diet on stroke, our results need to be replicated in other populations, especially men."
Related Health Concern: Stroke and Cerebrovascular Disease
Stroke prevention is a subject of much debate. Approximately 25 percent of people who recover from a first stroke will have a second within five years. While the chance of death and disability increases with each stroke, risk of another stroke appears to be greatest within the first year (National Stroke Association 2005).
Using measurements such as the degree of artery occlusion (how much of the carotid artery is blocked by atherosclerotic plaques), medical experts have sought to establish firm guidelines to help physicians choose between the various options, including medication, angioplasty, and surgery. Common prescription drugs used to help prevent stroke include antihypertensive agents (Gorelick PB et al 1999; Goldstein LB et al 2001), cholesterol lowering agents (statins), and antiarrhythmics to help control irregular heartbeats that might contribute to stroke risk. Angioplasty is a procedure in which a balloon is threaded into the artery and inflated rapidly, crushing the plaque against the arterial wall and opening the artery. The most common surgery used to prevent stroke is called carotid endarterectomy, in which the surgeon opens the arteries in the neck and strips away the inner lining of the artery.
While these strategies have been shown to work in specific circumstances, a common flaw also unites them: they are often used only after stroke risk has reached an unacceptable level. Life Extension prefers a much more proactive approach. By using advanced early screening tests to determine risk, then taking action to improve endothelial function and reduce blood risk factors (such as homocysteine and fibrinogen) and blood pressure, Life Extension seeks to maintain the lowest possible risk profile.
Multiple studies have found that a diet high in fruits and vegetables lowers risk of cerebrovascular disease and both ischemic and hemorrhagic stroke (Gariballa SE 2000; Sauvaget C et al 2003). Two major reviews recommended that public health policy promote increased dietary intake of antioxidant vitamin C, beta-carotene, vitamin E, B vitamins (including folate), potassium, calcium, magnesium, vitamin D, fiber, and omega-3 fatty acids to reduce risk of stroke (Gariballa SE 2000; Johnsen SP 2004). These vital nutrients can also be obtained through dietary supplements in conjunction with a healthy diet.