For decades, it has been known that high cholesterol levels are not good for the heart. High cholesterol levels have been associated with high blood pressure, increased risk of heart attacks, strokes and generalized narrowing of blood vessels.

Now there is a study that shows that moderately elevated levels of cholesterol in middle-aged adults may be an increased risk factor for developing Alzheimer’s disease and other dementias.

Researchers recently published data on 9,800 individuals who were followed for more than 4 decades for development of dementia. It was observed that individuals who had high or even moderately elevated levels of cholesterol in their mid 40s had a significantly increased risk of developing Alzheimer’s disease later in life.

In the past, scientists have always tended to think of the brain and heart as two distinct organs that are affected by different pathology. However, we are now learning that what is good for the heart is also good for the brain. This concept is now being applied by physicians in recommending changes in life style in middle age to help prevent onset of dementia.

The one minor negative of the study was that researchers did not distinguish between the HDL (good) and LDL (bad) cholesterol, chiefly because the significance of these different subtypes of cholesterol was not well understood forty years ago.

At present, the current guidelines mention that total cholesterol of 240 or higher is considered high, and a cholesterol of 200 to 239 is considered borderline high. Cholesterol levels less than 140-160 are being recommended.