Lowering Cholesterol: A Piece of the Heart Health Puzzle

The relationship between LDL cholesterol and cardiovascular diseases has been well-documented and summarized by the NIH's National Cholesterol Education Program.

Epidemiologic studies (i.e. research that associates the lifestyles of different populations or groups to a disease), laboratory studies (i.e. research into the effects of certain nutrients or medication on cells outside the body) and clinical studies (research on the effects of certain nutrients or medications on a living person) all show that cholesterol is a critical factor in the development of atherosclerosis.

Atherosclerosis occurs when plaque builds up on the walls of your arteries. This plaque leads to a narrowing and ultimate closing of an artery. Plaque also can break free of the arterial wall. It then can lodge further down your artery, causing a blockage that can lead to a stroke, heart attack, or a blood clot in your arms, legs or other parts of your body.

National Cholesterol Education Program Summary of Research

• Studies across different populations reveal that those with higher cholesterol levels have more arterial plaque and heart disease than those with lower levels. People who migrate from regions where average serum cholesterol in the general population is low to areas with high cholesterol levels show increases in their cholesterol levels as they acculturate. These higher levels in turn are accompanied by higher levels of heart disease.
• Atherosclerosis often can be identified in adolescence or early adulthood. The cholesterol level in young adulthood predicts development of heart disease later in life. In three prospective studies with long-term follow-up, detection of elevated serum cholesterol in early adulthood predicted an increased incidence of heart disease in middle-age.
• The power of elevated LDL to cause heart disease has been shown most clearly in persons with genetic forms of very high cholesterol. In these persons, advanced coronary atherosclerosis and premature heart disease occur commonly even in the complete absence of other risk factors. These disorders provide stronge evidence that LDL is a powerful cause.
• Since LDL-cholesterol levels of less than 100 mg/dL throughout life are associated with a very low risk for heart disease in populations, they can be called optimal. Even when LDL-cholesterol concentrations are near optimal (100–129 mg/dL), plaque formation occurs; hence, such levels must also be called above optimal. At levels that are borderline high (130–159 mg/dL), plaque formation proceeds at a significant rate, whereas at levels that are high (160–189 mg/dL) and very high (above 189 mg/dL) it accelerates further.
• A large number of clinical trials on cholesterol-lowering therapy have been carried out over the past four decades. The initial encouraging findings of earlier trials have recently been reinforced by the robust findings of a large number of studies.
  

The Research in Context: Only A Piece of the Puzzle

Lowering LDL cholesterol is not a guarantee of cardiovascular health. Many people on cholesterol-lowering medications still suffer heart attacks, strokes and other cardiovascular challenges. Similarly, LDL cholesterol levels above the "optimal" levels should not necessarily require an individual to proceed to a lifetime of cholesterol-lowering medications. Each of us should discuss this carefully with our medical providers.

In these conversations, however, you should recognize that cholesterol-lowering is only one piece of the puzzle. Some things to consider:

• Once built-up in your arteries, plaque is difficult to remove. Cholesterol-lowering therapies may only serve to reduce further development, but not fully remedy arterial health.
• The medical community also is investigating the role that different types of LDLs might play in the development of both plaque itself and the ability for plaque to remain “stable” and not break free from the arterial wall. This may be a factor even if LDL levels are low.
• Low levels (below 40mg/dl) of HDL cholesterol have been shown to be a risk factor for heart diseases and high levels (above 60mg/dl) have been associated with reducing the risk of heart disease and plaque development.

Beyond cholesterol management, cardiovascular health flows from different hereditary, environmental and lifestyle factors. It is a complex equation.

The important point: cholesterol management should be thought of as a lifetime approach, starting in your teens, to maintain cardiovascular health. Like weight-management and physical fitness, cholesterol management and its nutritional tools can promote long term health.