Everyone has been told that cholesterol is bad and can lead to heart disease, heart attack and stroke, but most may not realize that cholesterol also is created and used by the body to help keep us healthy. The liver makes all the cholesterol we need and circulates it through the blood.
A normal lipid profile suggests total cholesterol should be less than 200 milligrams per deciliter of blood, with high-density lipoproteins (HDL) cholesterol above 40, low-density lipoprotein (LDL) cholesterol below 130 and triglycerides below 150.
Current guidelines recommend prescribing statins to lower cholesterol, with the goal of reducing LDL levels to 70. The result is that cholesterol is removed from the body, but it’s important not to remove too much. The body needs a certain level of cholesterol and can be harmed without enough, according to Dr. L. David Shuler, a cardiologist with Mercy Clinic Cardiology – Carthage.
Dr. Shuler said that too little cholesterol can increase the risk of liver disease, dementia and Alzheimer’s disease.
“The result of statins is blocking the synthesis of cholesterol in the liver. It’s important to monitor liver function for patients on statins,” he said. “The brain contains 25 percent of a body’s cholesterol. If statins are removing cholesterol from the body, much of it is coming from the brain.”
When the landmark Framingham heart study looked at patients during the mid-1990s to early 2000s, it was noted that some had dementia or Alzheimer’s. Many of them also had low cholesterol levels.
Cholesterol is carried to the brain via the LDL receptor and is a building block for neurons. Reducing LDL levels too much “starves” the brain of cholesterol, according to Dr. Shuler.
Studies also suggest that statins can lead to type 2 diabetes in women. “If you follow women on statins in the Framingham study, they have a 48 percent higher incidence of type 2 diabetes than those not on statins,” he said.
In the mid-1990s, many suggested reducing fat and increasing carbohydrates to reduce cholesterol. Unfortunately, that made the problem worse. When people eat carbohydrates, it metabolizes into sugar. The pancreas, which produces insulin, is overwhelmed by sugar and turns it into fat.
As a result, Dr. Shuler said, obesity has become an epidemic.
Sugar exposed to proteins results in glycated protein, which is a deformed protein. LDL is a type of deformed protein that becomes inflamed plaque and connects to the wall of an artery. Thus, it’s not cholesterol, but glycated protein (hemoglobin A1C), that can cause atherosclerosis, which is hardening and narrowing of the arteries.
“If sugar intake is reduced, LDL no longer is bad cholesterol because it carries lipids, fats and antioxidants that help membrane formation,” he said. “If you deprive the brain of LDL, you can lose brain tissue and develop dementia. That’s exactly what these large studies are showing.”
A low-cholesterol diet only will lower cholesterol about 10 percent, so Dr. Shuler suggests making healthy eating choices, including reducing carbohydrates and sugars, and increasing exercise.