Eating a nutrient-dense breakfast has long been touted as a way to boost the brain’s memory and creativity. Now, Agricultural Research Service studies are showing that eating a healthful diet over a lifetime can improve the condition of the brain as people
Eating a nutrient-dense breakfast has long been touted as a way to boost the brain’s memory and creativity. Now, Agricultural Research Service studies are showing that eating a healthful diet over a lifetime can improve the condition of the brain as people reach their twilight years. “Dementia” is a general term for a loss of memory and other mental abilities that is severe enough to interfere with daily life. It is caused by physical changes in the brain. While Alzheimer’s disease is the most common type of dementia, there are other forms, including mild cognitive impairment.
Reducing Alzheimer’s Risk
Every 70 seconds, someone develops Alzheimer’s disease, says the Chicago, Illinois-based Alzheimer’s Association. Direct and indirect costs of Alzheimer’s and other dementias to Medicare, Medicaid, and businesses amount to more than $148 billion each year. To understand links between inadequate nutrition and brain degeneration, scientists use different approaches that involve cell culture, animal model, and human clinical studies.
A long-term study headed by physician Ernst Schaefer found that people who ate the greatest amount of oily fish rich in an omega-3 fatty acid, DHA, on a weekly basis appeared to cut their odds of dementia nearly in half. DHA (short for docosahexaenoic acid) is found in the brain, and scientists think it raises HDL, or good cholesterol; lowers harmful fats called triglycerides; and slows the buildup of plaque that can line blood vessels. DHA also seems to grease the wheels of neurons and synapses responsible for memory, language, and thinking. It is abundant in oily fish, such as salmon, tuna, mackerel, and herring.
Schaefer is the director of the Lipid Metabolism Laboratory at the Jean Mayer USDA Human Nutrition Research Center on Aging (HNRCA) at Tufts University in Boston, Massachusetts. He and colleagues analyzed the DHA blood levels of the nearly 900 men and women, ages 55 to 88, participating in the Framingham Heart Study. All participants were free of dementia at the beginning of the 9-year study.
The researchers ranked the participants into four groups, or “quartiles,” based on highest to lowest DHA blood levels. Participants with plasma DHA levels in the upper quartile experienced a significant 47-percent lower risk of developing dementia compared with participants with levels in the lower three quartiles. There was also a significant correlation between plasma DHA levels and both fish intake and DHA intake.
Participants who ate the greatest amount of oily fish averaged about three servings a week, which is equivalent to an average daily DHA intake of 180 milligrams. The study suggests that relatively higher oily-fish consumption over time correlates with a lower incidence of dementia in people over 75, according to Schaefer.
The study appears in a 2006 issue of the Archives of Neurology.
Genetics Still a Barrier
While ARS researchers are reporting links between various food 