The media have made us all familiar with the term “cholesterol.” Although most people tend to believe that there is a link between the cholesterol in their diet and heart disease, the experts consider this topic a controversial one because the scientifically established link is between blood, or serum, cholesterol and heart disease, not dietary cholesterol and heart disease. Only about 15 percent of blood cholesterol is from the diet; the rest we make in our own liver and in other cells. Research into fat, cholesterol, and heart disease is destined to continue for years to come. Meanwhile, here is what is known – so far.
Cholesterol is a complex, waxlike substance that the body needs for many vital processes. The brain, the nervous system, and all cell walls require some cholesterol. It is also important in creating hormones and vitamin D, and in aiding the digestion of fats.
The primary source of dietary cholesterol are foods of animal origin, with the greatest amounts of cholesterol found in red meats, eggs, dairy products, and some shellfish. Regardless of the amount you consume in your diet, your body continues to produce cholesterol every day. Your body will attempt to balance the cholesterol it manufactures with what it takes in, tending to produce less and to eliminate more in response to a high cholesterol diet. However, in some people the amounts of cholesterol in the bloodstream cannot adjust to overcome the effects of a high cholesterol diet.
Most healthy people maintain a fairly constant level of cholesterol in the bloodstream, although this level may rise with age. A diet high in polyunsaturated fats is associated with lower levels of blood cholesterol, whereas a diet high in saturated fats tends to increase the amount of cholesterol circulating in the blood – a condition that is a risk factor for heart disease.