The inclusion of unhealthy foods can reduce the positive effects of an otherwise healthy diet

Eating a healthy diet, such as the Mediterranean diet, has a positive impact on health, but little is known about the consequences of including unhealthy foods in an otherwise healthy diet. Now, researchers from Rush University Medical Center have reported that reduced benefits of a Mediterranean diet are eaten among people with a high frequency of unhealthy foods. The results of their study were published in 2008 Alzheimer’s and Dementia: The Journal of the Alzheimer’s Association on January 7th.

“Eating a diet that emphasizes vegetables, fruits, fish and whole grains can positively affect a person’s health,” said Puja Agarwal, Ph.D., a nutrition epidemiologist and assistant professor in the internal medicine department. medicine at Rush Medical College, said. “But when combined with fried foods, sweets, refined grains, red meat and processed meats, we noticed that the benefits of eating the Mediterranean part of the diet seem to be diminished.”

A Mediterranean diet is associated with a slower rate of cognitive decline in older adults.

The observational study included 5,001 older adults living in Chicago and were part of the Chicago Health and Aging Project, an evaluation of cognitive health in adults older than 65 years conducted from 1993 to 2012. Every three years, study participants completed a cognitive assessment questionnaire that tested basic information processing skills and memory, and completed a questionnaire on the frequency with which they consumed 144 food items.

The researchers analyzed how carefully each of the participants adhered to a Mediterranean diet, which included the daily consumption of fruits, vegetables, legumes, olive oil, fish, potatoes and unrefined grains, plus moderate wine consumption. They also assessed how much each participant followed a Western diet, which included fried foods, refined grains, sweets, red and processed meats, full-fat dairy products, and pizza. They assigned scores from zero to five for each food item to compile a total Mediterranean diet count for each participant in a range of zero to 55.

The researchers then examined the relationship between Mediterranean dietary points and changes in participants’ cognitive function, episodic memory, and perceptual speed. Participants with a slower cognitive decline during the years of follow-up were those who followed the Mediterranean diet most closely, along with restricted foods that were part of the Western diet, while participants who ate more of the Western diet had no beneficial effect. of healthy food components. in the delayed cognitive decline.

There was no significant interaction between age, gender, race, or education and the association with cognitive decline in high or low levels of Western dietary foods. The study also included models for smoking status, body mass index, and other potential variables such as cardiovascular conditions, and findings were the same.

“Western diets can adversely affect cognitive health,” Agarwal said. “Individuals with a high Mediterranean dietary score compared to those who achieved the lowest score were 5.8 years younger than they were cognitive.”

Agarwal said the results are complementary to other studies showing that a Mediterranean diet reduces the risk of heart disease, certain cancers and diabetes, and that it also supports previous studies on the Mediterranean diet and cognition. The study also noted that most nutritional patterns that show improved cognitive functions among older adults, including the Mediterranean, MIND, and DASH diets, have a unique matrix based on the amount of servings consumed for each dietary component.

“The more we can include green leafy vegetables, other vegetables, berries, olive oil and fish in our diet, the better it is for our aging brains and bodies. Other studies show that red and processed meats, fried foods and low whole grains. Intake is related with higher inflammation and faster cognitive decline in older age, “said Agarwal.” To benefit from diets such as the Mediterranean diet, or MIND diet, we will need to reduce our consumption of processed foods and other unhealthy foods such as fried foods and sweets. restrict.”

The study and its findings cannot be easily generalized. Future longitudinal studies on diet and cognition among the middle-aged population are needed to expand these findings.