Antioxidants help prevent Alzheimer's disease: research focuses on flavonoids and curcumin

Medical researchers have come to believe that some antioxidant compounds, called flavonoids, can help keep our brains healthy as we age. Flavonoids and other antioxidants have been shown to benefit the heart and reduce cancer risks. Now there is an increasing amount of evidence that they also protect healthy brain functioning and help prevent Alzheimer's disease and cognitive impairments that occur in many elderly people. Not all flavonoids we consume will reach the brain, and clinical trials with some antioxidants have not shown significant effects on preventing or reversing dementia, so researchers are focusing on some specific antioxidants as they identify nutrients that can help prevent or slow the development of Alzheimer's disease.

Antioxidants are biochemical compounds that neutralize dangerous oxygen free radicals. Free radicals are destructive molecules that damage cell walls and can corrupt DNA. Free radicals build up in the body when we are exposed to toxins from food, air, and beverages, and they are generated in our body when we experience stress. Thus, maintaining a healthy lifestyle and reducing stress in our lives is important to help prevent free radical damage. Part of a healthy lifestyle includes having a diet high in antioxidants and using natural antioxidant extract supplements to boost the body's ability to clear free radicals. Antioxidants are present in high amounts in many fruits and vegetables, and the overall level of these in a food is measured as the ORAC value, the oxygen radical absorbance capacity.

Scientists studying the brain and dementia now believe that flavonoids can also protect the brain through other mechanisms besides neutralizing free radicals. Recent studies looking at Alzheimer’s disease have concluded that green tea and grape flavonoids can reduce damage to the brain and in some cases improve mental performance. One group at King’s College London has focused on the flavonoid called epicatechin which is abundant in a number of foods, including cocoa. Dr. Robert Williams, the biochemist who lead the research, said: "We have found that epicatechin protects brain cells from damage but through a mechanism unrelated to its antioxidant activity." Other Alzheimer's researchers have focused on curcumin, a compound found in turmeric, the Indian spice used in curry. Curcumin has been found to reduce beta amyloid protein plaque buildup in the brain and scientists are now exploring how similar compounds found in ginger and rosemary spices might also affect this marker of Alzheimer's disease.

Alzheimer’s is closely associated with clumps of the disruptive beta amyloid protein that build up in the brain. Dr. Williams, who described his research at the British Pharmacological Society’s Summer 2009 Meeting in Edinburgh, said that flavonoids seemed to protect the brain against the buildup of these amyloid plaques. He concluded: "Although our findings support the general concept that dietary intake of flavonoid-rich foods or supplements could impact on the development and progression of dementia, they are clearly insufficient to make any sort of nutritional recommendations at this stage." This cautious statement should not discourage anyone from immediately enhancing antioxidant consumption - it merely indicates that the dosage and types of antioxidants that will specifically help prevent or treat Alzheimer's are topics that need more study.