December 6, 2021
Older men and women who ate a diet high in foods that fight inflammation were at lower risk of developing dementia, a new study found. Such foods as fruits and vegetables, fish, beans, coffee and tea were all tied to a lower dementia risk. The findings add to growing evidence that what we eat can have an impact on brain health, helping to ward off Alzheimer’s disease and other forms of dementia as we age.
“There may be some potent nutritional tools in your home to help fight the inflammation that could contribute to brain aging,” said study author Dr. Nikolaos Scarmeas of National and Kapodistrian University of Athens in Greece. “Diet is a lifestyle factor you can modify, and it might play a role in combating inflammation, one of the biological pathways contributing to risk for dementia and cognitive impairment later in life.”
The study looked at 1,059 men and women in Greece who were part of the large and ongoing Hellenic Longitudinal Investigation of Aging and Diet. Their average age was 73, and none had dementia at the start of the study.
The participants filled out detailed questionnaires about the foods they ate during the previous month. The researchers focused on foods that affect levels of inflammatory substances in the blood.
Some foods are known to fight inflammation, a form of low-grade, smoldering irritation that can damage organs throughout the body, including the brain. In general, the less processed the food, the better.
Inflammation-fighting foods include leafy greens like lettuce, spinach and kale and other vegetables; fish rich in omega-3 fats, like salmon, tuna and sardines; fruits like strawberries, blueberries, apples, oranges and cherries; nuts like almonds and walnuts; beans, lentils and other legumes; and heart-healthy fats like olive oil. Coffee and tea, which contain polyphenols and other anti-inflammatory compounds, are also helpful.
Other foods can promote inflammation that, over time, may contribute to Alzheimer’s disease, heart disease and other chronic ailments of aging. Foods that promote inflammation include refined carbohydrates like white bread, cake, white rice and pastries; sugary beverages; deep-fried foods; red meat; processed meats like salami and deli meats.
The researchers divided the participants into three groups, according to how inflammatory their diets tended to be. Over the next three years, 62 of them, or 6 percent, developed Alzheimer’s disease or other forms of dementia.
The researchers found that compared to the group who consumed the fewest inflammatory foods, those in the group that ate the most were three times more likely to develop dementia. The more inflammatory their diet tended to be, the greater their risk of dementia.
Those in the group with the highest inflammatory diet ate, on average, 9 servings of fruit, 10 of vegetables, 2 of legumes and 9 of coffee or tea per week. In comparison, those eating an anti-inflammatory diet tended to eat, on average, 20 servings of fruit, 19 of vegetables, 4 of beans or other legumes and 11 of coffee or tea per week.
The study was short, lasting only three years, but the link between inflammatory foods and increased dementia risk was statistically significant. And the results are consistent with earlier studies showing that a Mediterranean style diet, also high in anti-inflammatory foods, is likewise tied to a lower risk of Alzheimer’s disease.
“Our results are getting us closer to characterizing and measuring the inflammatory potential of people’s diets,” Dr. Scarmeas said. “That in turn could help inform more tailored and precise dietary recommendations and other strategies to maintain cognitive health.”
In addition to avoiding inflammatory foods, regular exercise has been shown to reduce inflammatory compounds in the blood over the long term. And if you are overweight, losing weight can also help to lower inflammation. Chronic stress also contributes to inflammation, so try to take steps to ease stress levels. Gum disease has likewise been tied to higher levels of inflammation, so getting regular dental cleanings may be a wise preventive. In earlier studies, all of these inflammation-fighting measures have been tied to a lower risk of Alzheimer’s disease.
By ALZinfo.org, The Alzheimer’s Information Site. Reviewed by Marc Flajolet, Ph.D., Fisher Center for Alzheimer’s Research Foundation at The Rockefeller University.
Source: Sokratis Charisis, Eva Ntanasi, Mary Yannakoulia, et al: “Diet Inflammatory Index and Dementia Incidence: A Population-Based Study.” Neurology, Nov. 10, 2021