The researchers found that people with larger midsections and normal Body Mass Index (BMI), a measure comparing weight to height, had an increased risk of late life dementia compared to those with smaller midsections and normal BMI. People who exhibited both obesity and larger midsections had the highest risk of dementia.
The mechanisms linking obesity to dementia are not well understood. The excess fat may increase blood glucose, which could conceivably affect brain function. And it goes without saying that large stomachs may be a proxy for reduced vascular health, which could affect the brain and other organ systems.
In interpreting this study, we should be careful not to focus exclusively on large stomachs as a simple causal factor at the expense of understanding the social environments that encourage unhealthy behaviors that, in turn, promote obesity.
Indeed, there are a wide range of influences in our surroundings -- service sector jobs requiring greater time commitments and less physical movement, faster paced lives and motorized transportation that discourage walking, easy access to cheap, unhealthy, fast foods, increasing levels of stress, disparities in income -- that promote obesity in individuals or populations.Some have termed our modern environments "obesogenic" for their propensity to encourage behaviors that cause us to take in more calories and move less. Promoting nutritional change will be impossible without first understanding the food meanings, practices and beliefs, and the factors that might constrain them, within a particular group.
