High Levels of Bad Cholesterol May Be Linked to Alzheimer’s Disease

Did You Know…that your high levels of bad cholesterol may be linked to Alzheimer’s?

The news on cholesterol can be confusing, as researchers scramble to determine how cholesterol levels affect overall health.  The relationship between cholesterol levels and heart disease is less clear than was once believed.  However, the impact of elevated cholesterol on brain health is clearer—and more concerning-than ever.


FACT: Elevated “bad” cholesterol may put you at significantly higher risk of Alzheimer’s disease. 

In 2010, Austrian researchers showed that a chronic high-cholesterol diet in rats produces brain damage similar to Alzheimer’s disease.  And in 2013, groundbreaking research published in JAMA Neurology and conducted by Bruce Reed clearly showed that this risk applies to humans, as well.

Reed is a professor of neurology at the University of California (UC) Davis, and associate director of its Alzheimer’s Disease Center.  “Our study shows that both higher levels of HDL (good) and lower levels of LDL (bad) cholesterol in the bloodstream are associated with lower levels of amyloid plaque deposits in the brain,” said Reed.  Amyloid plaques are a hallmark of Alzheimer’s disease.

Reed explained that long-standing evidence already shows that high cholesterol is associated with a higher risk of developing Alzheimer’s.  However, his team’s study is the first to link high cholesterol with the development of amyloid plaques in the brains of living people.

A Groundbreaking Study 

Reed’s study included 74 men and women aged 70 and over recruited from the Alzheimer’s Disease Center, stroke clinics, and community senior facilities.

The group included:

  • 3 people with mild dementia
  • 38 with mild cognitive impairment
  • 33 who were cognitively normal

All the participants underwent fasting blood tests as well as brain PET scans. The PET scans highlighted amyloid plaques via a radioactive tracer.  The findings?  Higher levels of “bad” cholesterol (LDL) and lower levels of “good” cholesterol (HDL) were linked to more amyloid plaques in the brain.

The findings were not affected by age of participants or by the presence of a specific gene linked to some forms of Alzheimer’s.


Protecting Brain Health by Controlling Cholesterol 

Study co-author Charles DeCarli is also a professor of neurology at UC Davis and director of its Alzheimer’s Disease Center.  He calls the team’s findings a “wake-up call” and says people can improve their chances of keeping their brains healthy later in life by controlling their cholesterol.  “If you have an LDL above 100 or an HDL that is less than 40, even if you’re taking a statin drug, you want to make sure that you are getting those numbers into alignment.  You have to get the HDL up and the LDL down,” he says.