2009 Studies & Research Blog

It’s no secret that obesity is something to be avoided - after all, if it weren’t a problem, the steady rise in overweight individuals wouldn’t be referred to as the "obesity epidemic," but rather the "obesity achievement" or the "portly party."  However, carrying more than a few extra pounds around isn’t something to be pleased about. In addition to driving away members of the opposite sex, love handles or a beer gut can mean that you have to buy an extra airplane ticket or worse, lead to the development of a number of adverse medical conditions.  One of the most common complications associated with obesity is Type 2, or "Adult Onset" Diabetes, which results from insulin resistance.  Additionally, obesity can lead to cardiovascular disease and a higher risk of stroke.

But these conditions aren’t the only incentive to keep off the extra pounds.  Recent research indicates that obesity can not only have unwanted effects on your body, but on your brain as well.  This research was based upon years of efforts, with individuals classified into three groups: normal weight, overweight and obese.  Normal weighted subjects were defined as those with Body Mass Indexes (BMI) of 18.5-25; overweight subjects had BMIs of 25-30; and obese subjects had BMIs of 30 and above.

And while one might expect that obesity’s negative effects are merely limited to physicality, the results found clear differences in the brain scans of each of the groups.  As the BMI of subjects increased, the concentrations of both Grey and White Matter in the brain decreased, suggesting that obesity led to atrophy in the brain tissue.  Most of the tissue reduction occurred in the frontal lobe, which is involved in higher mental functions such as decision making and assessing consequences; the hippocampus, which plays a role in spatial navigation and memory; the anterior cingulate gyrus, which is involved in emotion and regulation of blood pressure and heart rate; and the thalamus, which regulates periods of sleep and wakefulness and relays and processes sensory information.

As the researches noted, obesity and the adverse conditions associated with it " increase risk for cognitive decline and dementia."  And the degree of damage in the brain associated with obesity was not small; overweight subjects had four percent less brain tissue than normal weight individuals, while obese subjects had eight percent less brain tissue.

While some of the consequences of obesity have been long established by science, this research indicates that an unhealthy lifestyle can have many more significant adverse effects than most people comprehend.

SOURCE:

1. Raji, Cyrus A., et al. Brain Structure and Obesity. Human Brain Mapping, 2009.