Healthy diet is associated with better cognitive functioning in the elderly

A meta-analysis of studies exploring the links between diet quality and cognitive functioning in individuals aged 60 years and older revealed that those adhering to a healthy dietary pattern have 40% lower odds of suffering from cognitive dysfunction. The paper was published in Geriatric Nursing.

As people grow old, their cognition starts to change. During normal aging, cognitive processing speed gradually slows, working memory capacity decreases, and multitasking becomes more difficult. Vocabulary and general knowledge tend to remain stable or even improve with age, while skills that require rapid problem-solving may decline.

However, some people begin experiencing cognitive dysfunction as they age. Cognitive dysfunction in the elderly goes beyond normal age-related changes and includes significant impairments in memory, attention, language, or executive functions. Such dysfunction can result from neurodegenerative diseases like Alzheimer’s disease, vascular issues, or other medical conditions. Early signs often include frequent forgetfulness, confusion, and difficulty completing familiar tasks. These changes usually develop subtly and progress over years, depending on the underlying cause.

Study author Haoting Pei and his colleagues aimed to integrate findings from existing studies on the association between dietary patterns and cognitive function in older adults. Previous research has identified a variety of lifestyle factors linked to cognitive functioning in late life, including physical activity, cognitive stimulation, social engagement, and continuous learning. Maintaining a healthy diet has also been highlighted, but the strength of the association has remained unclear. The authors wanted to examine this link more systematically.

They searched the scientific databases MEDLINE, Scopus, PubMed, and Web of Science for studies reporting on dietary patterns and cognitive function among older adults. Eligible studies included participants aged 60 years or older, specified the dietary patterns being assessed, and used valid outcome measures of cognitive function.

The search resulted in 15 independent studies with a combined sample of more than 62,500 participants. Taken together, these studies indicated that older adults adhering to a healthy dietary pattern had 40% lower odds of experiencing cognitive dysfunction compared to their peers with less healthy diets. Although the results were highly heterogeneous across studies, the researchers found that no single study disproportionately influenced the overall findings.

“Therefore, in daily life, older adults should be encouraged to have a balanced intake of vegetables, fruits, fish, and legumes at each meal. However, whether some dietary components such as dairy products have beneficial effects on cognitive function in older adults is still controversial and further in-depth studies on them are needed in the future.”, study authors concluded.

A healthy dietary pattern in this study refers to diets shown in previous research to support overall health, such as the Mediterranean diet and the MIND diet. These patterns emphasize fruits, vegetables, whole grains, legumes, nuts, olive oil, moderate fish and poultry, and limited consumption of red meat, sweets, pastries, and fried foods.

The study provides evidence that healthy diets are linked to better cognitive outcomes in older adults. Still, the design of the included studies does not allow for definitive causal conclusions. While it is likely that healthy dietary patterns help protect cognitive health, it is also possible that older adults with stronger cognitive abilities are better able to access healthy foods and maintain beneficial dietary habits.

The paper, “Association of dietary pattern and cognitive function in the elderly: A systematic review and meta-analysis,” was authored by Haoting Pei, Sihan Liu, Longxin Li, and Min Zhou.