Is 'Bad Cholesterol' Really Good for You?

Dr. Perlmutter discusses how the concept that LDL, aka “bad cholesterol” is something that should be feared is unfounded.

LDL is what we call a carrier protein, and one of its important jobs is to carry a fundamentally important chemical to every cell in the body. This chemical is a critical component of cell membranes, serves as a brain antioxidant, and is the raw material from which your body manufactures vitamin D, cortisol, estrogen, progesterone, and testosterone. And this important, life-sustaining chemical is cholesterol.

So the notion that LDL is “bad cholesterol” is flawed on two counts. First, it is, in and of itself, not cholesterol, it is a protein. Second, now that you’ve embraced all of its functions in human physiology, it’s clear that LDL is anything but bad. How could we castigate a part of our biochemistry so fundamental for life?

LDL plays a particularly important role in brain health and function as you would expect based on the information above. In fact, you might expect that low levels of LDL might well be associated with compromise of brain tissue, and you would be right.

Earlier this month, researchers publishing in the prestigious journal, Neurology, designed a study to explore possible correlations between various markers of blood fats and risk for specific changes on MRI scans of the brain in 2,608 adults. The MRI changes in the brain they explored were changes associated with damage to small blood vessels, and, changes in the brain’s white matter associated with small strokes as these changes represent “powerful predictors of stroke and dementia.”

The researchers concluded that there was a strong correlation between these threatening brain changes and the blood measurement of triglycerides. While the reverse was true as it related to LDL. Meaning that higher levels of LDL were associated with less risk of the brain changes that are so worrisome.