Low Good Cholesterol Linked To Memory Loss

(July 1, 2008) - Having a healthy diet that raises your high-density lipoproteins (HDL), the so-called good cholesterol, not only helps your heart but your memory as well. (Read about "Dietary Guidelines" "Cholesterol") Low levels of HDL in middle age may increase the risk of memory loss and lead to dementia (Read about "Dementia") later in life, researchers reported in Arteriosclerosis, Thrombosis and Vascular Biology: Journal of the American Heart Association.

Observing 3,673 participants (26.8 percent women), researchers found that falling levels of HDL cholesterol were predictors of declining memory by age 60.

"Memory problems are key in the diagnosis of dementia," said Archana Singh-Manoux, Ph.D., lead author of the study. "We found that a low level of HDL may be a risk factor for memory loss in late midlife. This suggests that low HDL cholesterol might also be a risk factor for dementia."

The main findings are:

• At age 55, participants with low HDL cholesterol showed a 27 percent increased risk of memory loss when compared to those with high HDL.
• At age 60, participants with low HDL had a 53 percent increased risk of memory loss compared to the high HDL group.
• During none five year period, study members with decreasing HDL had a 61 percent increased risk of decline in their ability to remember words versus those with high HDL.

HDL cholesterol, which at high levels decreases the risk of heart attacks (link to h01), serves several vital biological functions. It helps clear excess cholesterol from the blood; assists nerve-cell synapses to mature; and helps control the formation of beta-amyloid, the major component of the protein plaques found in the brains of Alzheimer's patients. (Read about "Alzheimer's Disease") Dementia most often occurs in people 65 years or older, the fastest growing age group in the industrialized world.