Every 68 seconds, someone in the U.S. is diagnosed with Alzheimer’s disease, the neurodegenerative condition leading to memory loss, dementia, and eventual death. New research from Tufts University suggests a typical Western diet increases the chance of developing Alzheimer’s.
The study was conducted using mice. The researchers found that prolonged consumption of the western diet chow led to a dramatic increase in immune response activity in the brains of all mice, including those that don’t model Alzheimer’s disease. The diet greatly increased the activity of microglia, which function as the brain’s immune cells, and monocytes, circulating white blood cells that may cross into the brain in response to immune signaling. Some components of the western diet have been associated with the development of peripheral inflammation over time, and the study’s findings strengthen the possibility that immune activity in the brain increases Alzheimer’s disease susceptibility.
Researchers at Tufts have previously suggested that a hybrid dietary pattern of a Mediterranean-style diet and the DASH (Dietary Approaches to Stop Hypertension) eating plan may protect memory and thinking. A study reported that the MIND (Mediterranean-DASH Intervention for Neurodegenerative Delay) diet was associated with a slower rate of cognitive decline—equivalent to 7.5 years of younger age. Those with the highest MIND diet scores were 53% less likely to develop Alzheimer’s disease than those with the lowest scores.
“Inflammation and oxidative stress play a large role in the development and progression of Alzheimer’s disease,” says Tammy Scott, PhD, a scientist at Tufts’ HNRCA Neuroscience and Aging Laboratory. “The MIND diet particularly emphasizes foods, such as green leafy vegetables, berries and olive oil, which are rich in antioxidants and anti-inflammatory agents that may help to protect against dementia and cognitive decline.”
Martha Clare Morris, ScD, of Rush University, and colleagues developed the MIND diet score as a hybrid of the Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets.
Morris and colleagues noted that the results “suggest that even modest adjustments to the diet may help to reduce one’s risk of Alzheimer’s disease. For example, the MIND diet score specifies just two vegetable servings per day, two berry servings per week, and one fish meal per week.” Those recommendations are much lower and easier to achieve than comparable guidelines in the Mediterranean or DASH plans.
Another Tufts University study found that a high carbohydrate intake may be linked to a greater risk for cognitive impairment. Diets heavy in sugar and complex carbohydrates, such as processed grains, contribute to the risk factor by affecting the body’s glucose and insulin metabolism.