May 3, 2011
High levels of high-density lipoprotein, or HDL, the so-called “good” cholesterol, appear to protect against Alzheimer’s disease, according to a new report. The findings come from a study of older adults living in New York City who were followed for about four years.
Previous studies have shown that high levels of HDL seem to protect against heart attacks and strokes. Hence the name “good” cholesterol. The new findings, publishing in the Archives of Neurology, from the American Medical Association, suggest HDL has protective effects, not just for the heart, but for the brain as well.
In the study, researchers at Columbia University’s Taub Institute for Research on Alzheimer’s and the Aging Brain studied 1,130 seniors living in northern Manhattan. None had Alzheimer’s at the start of the study. All were given blood tests to assess their cholesterol levels, including levels of HDL.
During the follow-up period, 101 of the participants developed Alzheimer’s; their average age was 83. Men and women who had the highest HDL levels, measuring 55 milligrams per deciliter of blood or higher, developed 60 percent fewer cases of Alzheimer’s disease than those with the lowest HDL levels, of 38 milligrams or less. The protective effect persisted even after the researchers considered such Alzheimer’s risk factors as age, education levels and genes that predispose to the disease.
Professional medical guidelines recommend that men raise HDL levels that are under 40 milligrams per deciliter, and that women increase HDL numbers under 50 milligrams. An HDL of 60 milligrams or higher is considered optimal.
Regular exercise, and especially aerobic activities like walking, dancing or running, are thought to boost levels of “good” HDL cholesterol. Other studies have shown that regular exercise may likewise reduce the risk of developing Alzheimer’s later in life. Exercise also improves cardiovascular function, including blood flow to the brain. In addition, a heart-healthy Mediterranean diet, rich in fish, nuts and healthy oils like olive oil, is also recommended to keep the brain healthy into old age.
Christiane Reitz; Ming-Xin Tang; Nicole Schupf; Jennifer J. Manly; Richard Mayeux; José A. Luchsinger: “Association of Higher Levels of High-Density Lipoprotein Cholesterol in Elderly Individuals and Lower Risk of Late-Onset Alzheimer Disease.” Archives of Neurology, Vol. 67 (No. 12), pages 1491-1497.