The Myth of Cholesterol, Part I

Aug 17, 2010 | Articles, Nutrition

In my experience there is no current area of medicine that provokes stronger objection by many patients than the recommendation to use a statin, the family of medications that help lower LDL cholesterol (for example Lipitor or Crestor).  It seems that lots of people know someone that has had a painful muscle reaction to one of those medications.  There also seems to be a widely held opinion that the focus of so many doctors on cholesterol as the bad guy is a myth – perpetrated perhaps by drug companies.

There is some truth in that.  More than 75% of people who have a heart attack have normal cholesterol levels.  Over half of people who have elevated cholesterol do not have atherosclerosis, the factor that is considered essential to the development of the events elevated cholesterol is supposed to predict: stroke and heart attack.

The primary recommendations of most authorities is to eat a low cholesterol/fat diet even though clinical trials indicate this is only likely to lower cholesterol levels by 8% or less. We now know that prevention of strokes, heart attacks, and peripheral artery disease is pretty complex. While statins are clearly effective in reducing heart attacks and stroke, cholesterol should not be the sole focus of attention in those efforts.

Other risk factors need to be identified and addressed.  These include overweight and obesity, smoking, family history, blood pressure, levels of HDL – the good cholesterol, homocysteine, triglycerides, blood viscosity and coagulability, and especially c-reactive protein (CRP).  This latter marker is a measure of the degree to which inflammation is present and may be influencing the lining of arteries – the place where virtually all strokes and heart attacks originate.  Such inflammation, it turns out, is probably more dangerous than elevated cholesterol.

Another major factor is the development of insulin resistance.  Insulin is the hormone that helps control blood sugar.  When we eat a meal our blood sugar rises. How quickly it rises depends on the kind of food we eat.  Food high in simple sugars raises blood sugar quickly. Insulin works by opening gates in the cell membranes that allow sugar to flow into the cell where it can be used as a fuel to energize cell function.  Sugar inside cells is good, too much sugar in the blood is not.  Under conditions where a person is eating a lot of sugary foods, insulin begins to lose its effectiveness.  This is called insulin resistance and is the first step in the development of type 2 diabetes.  Insulin resistance is associated with complex changes in the blood including the production of bad LDL, the reduction of good HDL, increase in CRP and blood pressure and the accumulation of fat tissue – especially in the abdomen.  It can lead to the development of a condition called Metabolic Syndrome and this condition has a very high risk of cardiovascular disease indeed – many times riskier than having elevated cholesterol alone.

Cholesterol as a biological molecule is a good thing. We need cholesterol to make many important molecules including all of the sex and adrenal hormones.  Overly aggressive reduction in cholesterol may not be entirely good. There is concern that too aggressive lowering of LDL levels may have adverse effects including the development of some cancers, depression, and anxiety.  Pregnant women should not take statins because of the risk of premature birth and retardation of growth of the baby.

Reducing risk factors may be facilitated by better understanding of how inflammation, hormonal changes, increases in LDL, reduction in HDL, insulin resistance and the development of atherosclerosis and hypertension are all related. No disturbance of human metabolism calls more loudly for a holistic approach.

Although most health interest groups such as the American Heart Association and the American Diabetes Association advocate changes in diet and exercise as the first line therapy for the reduction of risk factors, most of my patients find little support for such changes from their physicians. Perhaps this is because there is little faith in the power of such an approach, or perhaps because of the complexity of such counseling.  Most primary care providers can spend very little time with their patients due to the pressures of insurance companies to see large numbers of patients to pay for the overhead of dealing with insurance companies.

In my next post I’ll try and explain how these various risk factors are related and how that may lead to a rational change in lifestyle that can pay huge dividends for years to come. A hint: it is not just about losing weight. Without an understanding of how these factors interplay, weight loss is not likely. If it is thought to be just a matter of less food in, more exercise out, that is most certainly a myth.