Alzheimer's Disease and Homocysteine
This is the VOA Special English Science Report.
Medical researchers say a new study shows a link between the mental condition Alzheimer's disease and high levels of the substance homocysteine (ho-mo-SIS-teen) in the blood.
Homocysteine is an amino acid present in proteins that are normally produced in the body. Homocysteine levels
Researchers at Boston University and Tufts University in Massachusetts carried out the new study. It is the first to find a link between high homocysteine levels in healthy people and the later development of Alzheimer's disease. The researchers reported their work in the New England Journal of Medicine.
They examined the medical records of people who took part in the Framingham, Massachusetts Heart Study. That study examined the health of several thousand people who live in a town near Boston. They have had medical tests every other year since Nineteen-Forty-Eight.
More than ten years ago, researchers measured the homocysteine levels of more than one-thousand healthy people taking part in the Framingham study. All the people were sixty-eight years old or older. Eight years later, ten percent of them had developed the mental and memory problems of Alzheimer's disease.
The researchers found that those with the highest homocysteine levels had two times the risk of developing Alzheimer's disease as those with lower levels. They said even a small increase in homocysteine levels appeared to increase the chance that the person would later develop Alzheimer's.
The study does not prove that high levels of homocysteine cause Alzheimer's. But, the researchers say homocysteine can damage blood vessels and nerves. High levels of homocysteine have also been linked to strokes and heart attacks.
Experts say some vitamins and folic acid in fruits and vegetables help change homocysteine into amino acids that do not harm the body. The researchers say people can reduce their homocysteine levels by eating more fruits and vegetables. Or they can take folic acid and vitamin B in pills. Scientists are planning to continue their work to find out if the vitamins can prevent or delay Alzheimer's disease in healthy people.
This VOA Special English Science Report was written by Nancy Steinbach.