Despite its nickname as the “good cholesterol” because of its cardiovascular benefits, high-density lipoprotein (HDL) cholesterol was linked to as much as a 42 percent increased risk for dementia in older people with very high levels of HDL, according to research published in a Lancet journal, the Lancet Regional Health – Western Pacific.

Although HDL helps remove cholesterol from people’s arteries, the researchers wrote that, at very high levels, HDL’s structure and actions change, and it “may become deleterious to health” in various ways.

For more than six years, they tracked 18,668 study participants, all 65 or older and all physically and cognitively healthy at the start of the study. In those years, cognitive dementia was diagnosed in 850 participants (4.6 percent).

Read more about what the research shows here.