Men and women have different obesity drivers, pointing to the need for tailored interventions

A recent study conducted by researchers from UCLA has found sex-specific brain signals that may indicate why men and women develop obesity differently. Published in the journal Brain Communications, the study combined data from multiple modes of MRI imaging with clinical features and personal histories of patients to identify sex-specific mechanisms in the brain associated with obesity. The study aims to help tailor obesity interventions based on an individual’s sex.

The researchers analysed data from 183 participants aged between 18 and 55, which included 42 males with a non-obese BMI, 23 males with a high BMI, 63 females with a non-obese BMI, and 55 females with a high BMI. All participants completed a battery of self-report questionnaires that assessed various factors, including childhood trauma, anxiety and depression, visceral sensitivity, food addiction, bowel symptoms, and personality traits.

The researchers conducted three different brain MRIs to assess the structure, function, and connectivity of each participant’s brain. They then analysed the data sets from the three scans, along with clinical information, using an analytical tool to identify a limited number of variables from multiple data sets to predict an outcome.

The results of the study showed that specific network connectivity changes were associated with high BMI, regardless of sex. The researchers also found that in females, brain regions and networks had alterations associated with early life trauma, consistent with previous studies that showed that females with obesity may have greater anxiety, lower resilience, and difficulty integrating emotions with action-directed goal planning. The study also revealed that females may be more susceptible to the sight, smell, and taste of highly processed foods.

According to the researchers, the study’s results suggest that tailoring treatment plans for females with a high BMI should focus on emotional regulation techniques and vulnerability factors. However, they note that the study identified associations, not cause and effect. Future studies are needed to determine whether changes in the brain are a factor in the development of obesity or a result of the condition. The study builds on previous research that examined sex-related differences in the prominence and signalling of brain regions in obesity, which showed that women’s obesity was associated with emotion-related and compulsive eating, while men’s eating behaviour tended to be affected by a greater awareness of gut sensations and visceral responses.