Studies regarding human beings as well as animals show a strong association between high cholesterol and atherosclerosis or heart disease. A researcher first noticed the connection among rabbits. This was followed by studies of monkeys which clearly showed the direct relationship between cholesterol and heart disease and saturated fat in our diet, cholesterol level in the blood and the development of atherosclerosis.
Correlation between High Cholesterol and Cardiovascular Disease
In one of the studies, a group of monkeys was fed with a diet rich in total fat, cholesterol and saturated fat. On the other hand, another group was fed a careful, balanced diet low in fat.The animals on the rich diet exhibited high levels of blood cholesterol and atherosclerosis in their coronary arteries as compared to the ones on the balanced diet.
Even studies involving humans have confirmed the correlation between high blood-cholesterol and heart disease and diet high in saturated fat and increased risk of atherosclerosis. In the early sixties, medical research determined that all countries did not have the same amount of atherosclerosis in their population. Countries with most heart disease cases had higher blood cholesterol levels and consumed more fat than countries with a lower rate of heart disease.
Relationship between Cholesterol and Atherosclerosis
One of the major studies in the nineteen eighties found a rather strong relationship between death rate due to coronary heart disease and high blood cholesterol levels.
The rigorous study spread over six years followed approximately three hundred and sixty one thousand men aged between thirty-five and fifty-seven with no history of heart attack. It was found that –
- The risk of death from coronary heart disease increases gradually at blood cholesterol levels of 180mg/dL
- Speeds at about 200mg/dL
- Doubles at about 220mg/dL
- And increases three times at about 245mg/dL.
In this study, the bad effects of high cholesterol were separated from other major risk factors which included cigarette smoking and high blood pressure.This helped to prove that at least in middle aged men, cholesterol by itself is a risk factor for atherosclerosis.
Another heart study found that –
- At any given age, for every one percent increase in blood cholesterol, the rate of heart attack rose by two percent starting at about 200 mg/dl.
- There was ten percent risk of coronary artery disease when people had blood cholesterol levels of 200 mg/dl or lower.
- People faced eighteen percent risk when their levels were 240 mg/dl or higher.
- It simply means that one person among ten with cholesterol lower than 200 mg/dl and about two people among ten with cholesterol higher than 240 mg/dl can develop heart disease.
Genes and Cholesterol
- It is true that in spite of dietary measures some people get inherited disorders which keep their cholesterol or triglyceride level high. And on the other hand, some lucky people can eat anything they want and still never have a problem with high cholesterol. But most people fall somewhere in between.
- There are variations in the results of low-fat, low cholesterol diet. Cholesterol levels of some people hardly change at all, whereas in others it can drop to 100 mg/dL or more. But the number of people who are truly resistant to dietary changes is not exactly known. Most studies simply look at the average decline in cholesterol. And researchers assume that non-compliant people (not following the diet) will not respond to the treatment.
Ways Of Reducing Cholesterol
- One type of study wherein every bite is controlled showed that it is indeed rare for a person not to respond at all to diet. So the only method to know the response to a diet and if one is truly diet resistant is to try a particular diet and see if it lowers the cholesterol. A low-fat diet may also reduce symptoms of chest pain and fatigue if one is already having a heart disease.
- Most doctors believe that cholesterol levels are raised due to too much fat in the diet, especially saturated fat. Countries which normally have a low-saturated fat diet have cholesterol level of 160 mg/dL or lower on an average. But when the same people switched over to a high-fat diet their cholesterol levels rose along with their risk of heart disease. Doctors strongly feel that most people can lower their cholesterol with a sufficiently low-fat diet and can shrink artery blockages slightly in some cases.