Search the world's information, including webpages, images, videos and more. Google has many special features to help you find exactly what you're looking for.What Causes Heart Disease? Price Foundation. Read this in. Nederlands. Fran. In broad outlines, this theory proposes that when we eat foods rich in saturated fat and cholesterol, cholesterol is then deposited in our arteries in the form of plaque or atheromas that cause blockages. If the blockages become severe, or if a clot forms that cannot get past the plaque, the heart is starved of blood and a heart attack occurs. Many distinguished scientists have pointed to serious flaws in this theory, beginning with the fact that heart disease in America has increased during the period when consumption of saturated fat has decreased. We don’t know enough to say for sure but we do have many clues; and although these clues present a complicated picture, it is not beyond the abilities of dedicated scientists to unravel them. Nor is the picture so complex that the consumer cannot make reasonable life- style adjustments to improve his chances. What Is Heart Disease? Coronary Heart Disease (CHD) is not a single disease, but a complex of diseases of varied etiology. Some of the recognized causes of heart disease include damage to the heart muscle or valves due to a congenital defect; or to inflammation and damage associated with various viral, bacterial, fungal, rickettsial or parasitic diseases. Rheumatic fever or syphilis can lead to heart disease, as can genetic or autoimmune disorders in which cellular proteins in the heart muscle are deranged or which disrupt enzymes affecting cardiac function. These factors probably contributed to most cases of heart disease recorded in the early part of the century, when rates of infectious diseases were much higher and antibiotics were not in use. Nevertheless, according to CDC statistics, heart disease was relatively rare in 1. US (http: //www. cdc. In 1. 99. 8, CHD (including stroke) accounted for about 3. One reason for the decline is the fact that victims of heart disease are living longer, due most likely to improved surgical techniques, the advent of angioplasty and the use of anti- clotting drugs given to heart attack victims. But the morbidity rates—the incidence of heart disease—remains high. Of greatest concern is the high rate of heart disease in American men between the ages of 4. The interesting thing is that most cases of heart disease in the twentieth century are of a form that is new, namely heart attack or myocardial infarction—a massive blood clot leading to obstruction of a coronary artery and consequent death to the heart muscle. Myocardial infarction (MI) was almost nonexistent in 1. Paul Dudley White, who introduced the electrocardiograph machine to America, stated the following during a 1. American Heart Association televised fund- raiser: “I began my practice as a cardiologist in 1. The Cleveland Clinic uses weight loss surgery as a treatment for type 2 diabetes, although this method has a much higher risk of complications. Switzerland (/ . It consists of 26 cantons, and the city of Bern is.
I never saw an MI patient until 1. By 1. 96. 0, there were at least 5. MI deaths per year in the US. Rates of stroke have also increased and the cause is similar—blockage in the large arteries supplying the brain with blood. The factors that initiate a heart attack (or a stroke) are twofold. One is the pathological buildup of abnormal plaque, or atheromas, in the arteries, plaque that gradually hardens through calcification. Blockage most often occurs in the large arteries feeding the heart or the brain. This abnormal plaque or atherosclerosis should not be confused with the fatty streaks and thickening that is found in the arteries of both primitive and industrialized peoples throughout the world. This thickening is a protective mechanism that occurs in areas where the arteries branch or make a turn and therefore incur the greatest levels of pressure from the blood. Without this natural thickening, our arteries would weaken in these areas as we age, leading to aneurysms and ruptures. With normal thickening, the blood vessel usually widens to accommodate the change. But with atherosclerosis the vessel ultimately becomes more narrow so that even small blood clots may cause an obstruction. The other half of the MI equation is the blood clot or thrombus that blocks blood flow to the heart or brain. Thus, any search for the causes of heart disease must consider complex factors in the blood that promote clotting at inappropriate times, that is, other than in response to bleeding from a rupture or wound. In fact, while a great deal of attention has been focused on the cause and solution to atherosclerosis, the role played by clotting factors in the blood has been relatively neglected. Yet a heart attack due to a clot can occur even in the absence of arterial blockages. Inflammation may also cause blockages. In fact, a new view of coronary artery disease is that it is an inflammatory process, characterized by cycles of irritation, injury, healing and reinjury inside the blood vessels. The inflammatory response is actually a defense mechanism that helps the body heal but when the inflammatory process goes awry, plaques may rupture, provoking clots that lead to heart attacks. The health and integrity of the blood vessel walls is another factor that must be considered. Aneurysms, the dilation and rupture of blood vessels due to weakness in the vessel walls, will naturally provoke a clotting response, not to mention the more immediate danger of rapid blood loss. In addition, biochemical imbalances in the smooth muscle cells may result in spasms that can be just as effective as a blood clot in cutting off blood flow to the heart. Finally, arrythmias—abnormalities in the rhythm of the heart’s pumping mechanism—can lead to interrupted blood flow, oxygen starvation of the heart muscle or complete shut down of the heart—the so- called cardiac arrest. Regulation of the nervous impulses that govern the heart depends on a large number of factors—from mineral status to the integrity of the myelin sheath. Known Risk Factors. There are dozens of risk factors for heart disease. Those cited most often by medical orthodoxy include high blood cholesterol, smoking, lack of exercise, stress and overweight. A high level of cholesterol in the blood is a mild risk factor for individuals with familial hyper- cholesterolemia (cholesterol levels chronically above 3. One factor of apparent importance is smoking, which has been associated in many studies with an increased risk of coronary mortality, even after correction for other risk factors. It is easy to speculate on the mechanism by which smoking causes heart disease. Exposure to fumes containing free radicals may promote the growth of atherosclerotic plaques. Perhaps chronic carbon monoxide intoxication limits the heart’s utilization of oxygen. But the picture is more complex than simple cause and effect. In a multi- year British study involving several thousand men, half were asked to reduce saturated fat and cholesterol in their diets, to stop smoking and to increase the amounts of unsaturated oils such as margarine and vegetable oils. After one year, those on the “good” diet had 1. In a study of Indians from Bombay and Punjab, researchers found that those from Punjab had one- fifth the number of heart attacks even though they smoked eight times more cigarettes. And while smoking was widespread at the turn of the century, myocardial infarction was not. This suggests that there may be factors in traditional diets that protect against the negative effects of smoking. It also raises the question of whether additives now used in cigarette paper and filters and changes in the curing process itself have exacerbated the harmful effects of cigarette use. Perhaps the association between smoking and heart disease is really an association with some other factor—stress, biochemical imbalances, nutrient deficiencies—that creates the desire or the need to smoke. Often when people quit smoking they become nervous and overweight, which may seem a bad bargain of one risk factor in exchange for two more. Regular physical activity is one of the few risk factors that has proved consistent. In all studies, regular physical activity is inversely associated with mortality from CHD, and physical activity is the only factor that has shown dose- response in the trials. Common sense tells us why exercise may be beneficial. When we exercise, our heart beats more rapidly, the arteries widen to provide more oxygen and arterial blood flow improves. Lack of exercise may also be a risk factor because it is a marker for something else that is the true cause. People who are overweight, for example, are less inclined to exercise. Prosperous people who have leisure time are more likely to exercise than those who must work long hours to make ends meet—and we know that heart disease in westernized nations is more prevalent among the poor. Dietary factors may make people less inclined to exercise. An interesting finding in the Framingham study was that those who ate the most saturated fat, the most calories and the most cholesterol were the most physically active. They also weighed the least and had the lowest levels of serum cholesterol! Common sense also tells us why overweight may be a risk factor. People who are overweight are less inclined to exercise. They probably eat large quantities of refined foods that provide lots of calories but little nourishment. They may have biochemical imbalances that contribute not only to overweight but also to some of the many aspects of heart disease, such as the tendency to form blood clots. Many doctors have noticed that heart attack strikes in the months just after severe emotional trauma—loss of a spouse or close friend, bankruptcy, layoff or disappointment. We know that grief changes many aspects of the body chemistry, making us more vulnerable to all sorts of diseases—not just heart disease but also cancer, allergies, tuberculosis and depression. But mankind has always suffered loss and grief. The question is why these traumas cause heart attacks today but did not in 1.
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