Auburn -- Researchers believe an amino acid already linked to heart disease and stroke may also contribute to a higher risk of Alzheimer's disease. Individuals with high blood levels of this amino acid, known as homocysteine, face twice the average risk of developing Alzheimer's disease, one of several forms of dementia that typically strike in old age. Researchers have not yet established a direct causal link between high blood levels of homocysteine and Alzheimer's disease. "It could be that homocysteine is merely an effect of Alzheimers disease rather than a cause," says Dr. Robert Keith, an Alabama Cooperative Extension System nutritionist. Since people suffering from Alzheimer's and other forms of dementia typically do not eat as well as other people, it could be that the high blood levels of homocysteine are merely a reflection of their poor eating habits, he says. Even so, scientists have determined that people suffering from Alzheimer's disease have abnormaly high blood levels of homocysteine exceeding 15 micromoles per liter of blood. They also belive that high blood levels of homocysteine, which cause damage ot blood vessels and nerves, could be a direct cause of heart disease and strokes - damage that may also contribute to brain damage and, ultimately, the dementia associated with Alzheimer's disease. "Blood vessels feed ozygen to the brain just as they do the heart muscle," Keith says. "So it follows that high blood levels of homocysteine may also be causing damage to the brain." For these reasons alone, Keith believes reducing blood levels of homocysteine to below 10 micromoles per liter of blood is worth the effort, if only to reduce the risk of heart disease and stroke. High blood levels of homocysteine are partly caused from consuming diets low in B vitamins. Reducing homocysteine blood levels typically involves increasing one's intake of three common B vitamins: B-6, B-12 and folic acid. B-12 and B-6 are commonly found in animal products, while folic acid is readily available in green, leafy vegetables, orange juice, and fortified breads and cereals, Keith says. These vitamins work by converting homocysteine into another more benign amino acid. Lowering one's blood level of homocysteine appears to be only one of several lifestyle changes that may reduce the risk of Alzheimer's and other forms of dementia. Maintaining strenuous mental activity throughout life also appears to be a vital safeguard. "It sort of boils down to the old saying, use it or lose it," Keith says. "If you keep your brain active throughout your life through mental stimulation, such as reading or working crossword puzzles, you probably will face a reduced risk of developing Alzheimer's disease or another form of dementia." "With less mental activity, you lose those neuronal connections and your brain, in a manner of speaking, begins to atrophy, almost like unused skeletal muscles," He adds. Antioxidants, such as vitamins C and E, widely available in fruits and vegetables, also appear to play a role in preventing Alzheimer's disease and other forms of dementia. "There is a connection between having these antioxidants in your diet and lowering your risk of these diseases later in life," Keith says. Indeed, studies have shown Alzheimer's disease tends to be more prevalent among people with low blood levels of antioxidants, while people with high levels of these compounds develop this form of dementia less frequently. While including large amounts of antioxidants in your diet will not produce instant effects, they could be decisive in the long run, Keith says. "People shouldn't assume they can reduce their risks of Alzheimer's right away by increasing their antioxidant intake, " Keith says. "It's a lifestyle choice that produces subtle effects over many years. We're talking about a long-term process here. Again, the best way to get these antioxidants into your diet over the long haul is to include more fruits and vegetables in your diet." Source: Dr. Robert Keith, Extension Nutritionist |