Can HDL be too high?

Jennifer Berry wrote an article that was reviewed by Daniel Murrell, MD, that explained more about the HDL.  We seem to think that cholesterol should be as low as possible as we all know it is well-documented as a risk factor for heart disease.

According to the Centers for Disease Control and Prevention there are tens of millions of Americans that take cholesterol-lowering drugs, or should be taking them.  The high-density lipoprotein (HDL) cholesterol is known as “good” cholesterol and actually beneficial for the heart.  But, what are the healthy levels and what happens if HDL falls out of range?

Low-density lipoprotein (LDL) cholesterol contributes to the fatty buildup that can clog the arteries.  The buildup clogs or narrows the arteries and a heart attack or stroke is more likely to occur, so lower is better for your LDL.

HDL cholesterol is useful for the heart as it may remove LDL cholesterol from the blood and transport it to the liver where it can be processed and eliminated.  Therefore, a higher HDL number is desirable as it signals a lower risk of heart disease.

HDL does protect the heart but no upper limit has been established and does not naturally elevate to unhealthy high levels in those with normal cholesterol processing and metabolism.  There are rare cases where HDL can become too high.

The journal Science reports a rare genetic variant that may cause high HDL levels.  The genetic variant alters the way that HDL works in the body and can increase the risk of heart disease.  This variant is found in a specific molecule known as SR-BI where the mutation causes increased levels of HDL and an increased risk of heart disease.

Another study performed found people who recently had a heart attack and had both high HDL and high levels of a substance called C-reactive protein were at higher risk of having another cardiac event.  The liver produces C-reactive protein when inflammation occurs in the body.  Circulation reported a study that found a defect in a specific protein known as cholesterol ester transfer protein may also cause abnormally high HDL levels and an increased risk of heart disease.  This was detected in women but not men.

It is recommended by the American Heart Association that all people ages 20 and older get a cholesterol test at least every 4 to 6 years.  American Academy of Pediatrics recommend children between the ages 9 and 11 have a cholesterol test.  Those children with a family history of high cholesterol should be tested between ages 2 and 10 years.

Total cholesterol level is less than 200 mg/dl, 200-239 as borderline high and above 240 is high.  The LDL levels should be less than 100 mg/dl, 100-129 for near optimal, 130-159 borderline, 160-189 high and 190 and above is very high.  The HDL, if less than 40 mg/dl is a heart disease risk, 40-59 is better and greater than 60 mg/dl protects against heart disease.

A common problem is having low HDL and high LDL.  AHA states that heart disease accounts for 1/3 of all deaths in the US.  Other heart disease risk factors include age, weight, diet, activity level, blood pressure and lifestyle factors.  Experts recommend to achieve healthy cholesterol levels you should get a cholesterol check at least every 5 years, eat a heart-healthy diet rich in fruits, vegetables, whole grains and lean protein, limit saturated fats, fried foods, salt and sweets, exercise for 30 minutes 4 to 5 times per week and do not smoke.

Dr Fredda Branyon