Study Finds Mediterranean Diet and Weight Loss Improve Gut Health and Cognitive Function in African American Obese Adults
A recent study published in the Nutrients Journal explored the effects of the Mediterranean Diet (Med Diet) and intentional weight loss (IWL) on the gut microbiome and cognitive function in African American obese adults. The researchers conducted a post hoc analysis of the Building Research in Diet and Cognition (BRIDGE) trial and examined whether these interventions had any impact on gut microbiota structure, abundance, butyrate production potential, and cognitive function.
Alzheimer’s dementia (AD) is a growing concern, and African American adults have a higher risk of developing AD due to factors such as obesity and poor food quality. Detecting and preventing AD during the mild cognitive impairment (MCI) stage has been a focus of research. Diet and weight are known risk factors for AD, with the Western diet having negative effects on amyloid-beta levels and cerebral perfusion. On the other hand, the Med Diet and IWL have been shown to protect against AD and improve cognitive performance.
The Med Diet is known to reduce inflammation, oxidative stress, and cognitive decline, all of which are risk factors for AD. In addition, the gut microbiome may play a role in boosting cognition, and a Med Diet along with IWL might increase microbial diversity and fecal anti-inflammatory compounds, such as butyrate.
The study analyzed data from 185 participants who were divided into three groups: a lifestyle program following a Med Diet (MedA), a Med Diet combined with calorie restriction for weight loss (MedWL), and a control group following a usual diet. The participants were instructed to maintain their diet and exercise routine throughout the 14-month intervention.
The results showed minimal impact on the gut microbiota composition, but Med Diet adherence scores were correlated with improvements in learning, memory, and recognition. The MedWL group, which experienced weight loss, showed gut microbiome changes associated with anti-inflammatory effects. The Med Diet interventions also had positive effects on cognitive performance, particularly in mental abilities such as attention, executive function, and learning and memory.
However, the study had limitations, including the small sample size, self-reporting of food intake, and the lack of randomization. Further research is needed to explore the underlying mechanisms and to support the implementation of dietary interventions in clinical settings.
Overall, this study provides evidence that adopting a Med Diet, with or without calorie restriction, can have beneficial effects on the gut microbiome and cognitive function in African American obese adults. These findings suggest that dietary interventions could be a potential strategy to improve gut health and mental abilities in this population.