Heart disease has been the leading cause of death in both men and women for the past twenty years in the United States. The term heart disease is more accurately a disease of the coronary arteries. These arteries supply blood to the heart muscle. When the blood supply through these arteries is diminished, symptoms arise. If the blood supply becomes completely blocked a heart attack or myocardial infarction occurs. The amount of time that passes before the blood supply is restored and the size of the area involved determines the outcome. Each year approximately one million Americans experience this event. The research into understanding and preventing this disease has been extensive. Medical researchers wanted to know what exactly caused the disease and what factors contributed to the disease process.
The easiest part of understanding heart disease was discovering what victims of the disease had in common. We call these risk factors of heart disease. These factors contribute to heart disease. The five major risk factors are smoking, high blood pressure, diabetes, high cholesterol, and heredity. Minor risk factors are obesity, lack of exercise, age and sex. Scientists have known these risk factors for over fifteen years. There has been an effective program of getting this information to the public. The result has been a significant reduction in smoking. There has also been better screening and treatment of high blood pressure, high cholesterol and diabetes. Unfortunately, the number of heart attacks has remained about the same.
The research into what exactly causes the plaques that form in the coronary arteries has been much more difficult. It is clear that this is not simply excess low-density lipoproteins (LDL) clogging the arteries. Analysis of the plaques indicated a matrix of inflammatory cells and material mixed within the LDL cholesterol. There appears to be an inflammatory process involved. The exact origin of this inflammatory process and the role it plays in the location, formation, and progression of plaques is not known. However, the search is on to discover what may be causing this inflammatory response.
The search for the origin of the inflammation lead researchers to investigate homocysteine as a possible risk factor in heart disease. Homocysteine is a non-essential amino acid that is a by-product of the normal metabolism of the essential amino acid methionine. Methionine is found abundantly in all the animal meats we consume. The body needs three B vitamins to metabolize methionine normally. Folic acid, B6 and B12 are the nutrients required to convert methionine to cysteine, which is then excreted by the kidneys. When these nutrients are not present in adequate amounts, methionine metabolism produces an intermediate substance called homocysteine. The homocysteine remains in the bloodstream until the nutrient levels become adequate to convert it to cysteine and the normal excretion process is restored. What interested researchers about homocysteine was the fact that they discovered that individuals who had genetic defects that prevented the normal metabolism of methionine and therefore, had chronically high levels of homocysteine in their bloodstream were at an especially high risk for heart disease. In fact, they were likely to have advanced disease at a very young age. What was it about homocysteine that caused this to happen?
It turns out that homocysteine is very irritating to the most outer lining of arterial walls. The amount of irritation is directly proportional to the amount of homocysteine in the blood. The higher the homocysteine level the more severe the vessel wall irritation. This is exactly the kind of irritation that would produce the inflammatory response found in the plaque analysis.
The next thing researchers did was to evaluate the effects of moderately elevated homocysteine levels over a prolonged period. Again, the data suggests a strong correlation between homocysteine and the risk of heart disease. Individuals with consistently low levels of blood homocysteine had very low rates of heart disease. The rate of heart disease rose along with the presence of higher levels of homocysteine. An abnormal homocysteine level greater than 20mg/dl was a five times greater predictor of heart disease than an abnormal cholesterol level. Darryl Kile, a well-conditioned professional baseball player died at age 33 from heart failure that could have been caught except for undetected extremely high homocysteine levels.
It cost about $40 to check for an elevated blood homocysteine level. Most doctors do not routinely run this test. Why? Until recently many medical insurance companies did not pay for it and the role of homocysteine and heart disease is still investigational. There is another reason why routine screening may never become common practice. It is because the treatment for an elevated homocysteine level is so simple. For most individuals, a daily multivitamin would provide adequate amounts of the folic acid, B6 and B12 the body need to insure normal methionine metabolism. Add Omega-3 fatty acids and the body has essential all-natural warriors fighting heart disease.
It is important for fitness professionals to know about homocysteine. Many of your clients want to lower their risk of heart disease. They want to establish better cardiovascular health by losing weight and getting regular exercise. The fact that many dieters now consume even more protein than ever before means that adequate daily levels of folic acid, B6 and B12 and Omega-3 fatty acids are even more important than ever.