A new study suggests that mild daily calorie restriction in the elderly could improve cognition. The study compared the effectiveness of the MIND diet, a combination of the Mediterranean and DASH diets, with mild calorie restriction on cognition in individuals with a family history of Alzheimer's disease. The results showed that both the MIND diet and calorie restriction had a positive effect on cognition, with no significant difference between the two. These findings suggest that mild calorie restriction and weight loss can support cognitive function in older individuals. The study was published in the New England Journal of Medicine.
The Normal Cognitive Changes Related to Aging
As individuals age, it is common to experience slight declines in memory and processing speed. These changes usually start in the twenties and thirties but are accompanied by an improvement in cumulative knowledge until advanced age. However, no single nutrient has been identified as a prevention method for cognitive decline. Observational studies have suggested that the Mediterranean diet may have beneficial effects on cognition.
The Study Design and Participants
In this study, researchers recruited 604 individuals with a family history of Alzheimer's disease who followed suboptimal diets but showed no signs of cognitive decline during testing. All participants had a body mass index (BMI) greater than 25, indicating they were overweight. The participants were randomly assigned to two groups: one group followed the MIND diet, while the other group continued their usual diet. The daily caloric intake of all participants was reduced by 250 calories with the aim of achieving a 3-5% reduction in body mass.
Follow-Up Visits and Cognitive Tests
Throughout the three-year study period, participants were instructed to follow their assigned diets and had regular dietary monitoring through phone and in-person consultations. Both groups received guidance on portion sizes, and those following the MIND diet were also given information on specific foods to include and avoid.
Researchers conducted four follow-up visits with the participants to assess their mental abilities, blood pressure, diet, physical activity, health conditions, and medication use. Cognitive tests were administered at six months, 12 months, 24 months, and 36 months. Some participants also underwent MRI scans to identify any potential brain changes.
Cognitive Improvements and Weight Loss
Both groups showed slight improvements in cognitive scores over the three years, but there was no significant difference between the MIND diet group and the group following their usual diet. Additionally, MRI results did not show any significant differences.
Participants in both groups lost an average of 5 kg during the trial. The researchers believe that weight loss may explain the observed improvements in cognition. Previous studies have found a link between weight loss and improved cognitive function, as weight loss has many overall health benefits, such as reducing the risk of heart disease, insulin resistance, and certain cancers. Weight loss also reduces inflammation, which is believed to have a positive effect on cognition.
Conclusion
In conclusion, a study comparing the effects of the MIND diet and mild calorie restriction on cognition in the elderly found no significant difference between the two. Both approaches showed positive effects on cognitive function, suggesting that mild calorie restriction and weight loss can support cognition in older individuals. These findings provide valuable insights into potential lifestyle interventions for cognitive decline in aging populations.
