Adopting and sticking to a healthy eating plan, such as the Mediterranean diet, is known to have a positive impact on seniors’ health and wellness … including their cognitive health. However, far less is known about the cognitive effects of indulging in unhealthy foods on an otherwise healthy diet.
Researchers at Rush University Medical Center in Chicago took on that question in a long-term study of people taking part in the Chicago Health and Aging Project, which monitored the cognitive health of about 5,000 adults over age 65.
After analyzing their eating habits in detail over nearly 20 years, few or no brain benefits of a Mediterranean diet were found among those who frequently ate unhealthy foods along with healthy ones.
The researchers analyzed how closely each participant followed the Mediterranean diet plan, which includes daily consumption of fruit, vegetables, olive oil, fish, potatoes and whole grains, plus moderate wine consumption. They also measured how many elements of a more Western diet – like fried foods, refined grains, sweets, red and processed meats, full-fat dairy products and pizza – were included in their diets on a daily basis.
They assigned scores of zero to five for each food item to compile a total “Mediterranean diet score” for each participant, ranging from zero to 55. Every three years, the study participants also completed a cognitive assessment questionnaire that tested their basic information processing skills and memory.
Participants who experienced slower cognitive decline over the years of follow-up were those who adhered to the Mediterranean diet most closely while limiting “Westernized” foods. On the other hand, those who ate more Western diet-based foods experienced few or none of the benefits from the healthier foods in their diet as far as slowing their rate cognitive decline.
In fact, people who had the highest Mediterranean diet scores were found to be nearly 6 years younger in age cognitively compared to those who had the lowest scores.
The results of the study were published in January in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.