(NaturalNews) While the talking heads on TV frantically warn about the so-called swine flu pandemic that is supposedly on the verge of causing world-wide suffering and death, there's another world-wide health problem of enormous proportions that's here, right now -- being overweight. The World Health Organization (WHO) estimates more than 300 million people across the planet are obese, and another billion more are overweight. Being too fat isn't a cosmetic problem, it's a condition that kills people prematurely by leading to cardiovascular disease, high blood pressure, stroke and type 2 diabetes. And now there's evidence that being too fat also causes brain degeneration and maybe even Alzheimer's disease.
In a study just published in the current online edition of the journal Human Brain Mapping, a research team headed by Paul Thompson, senior author and a University of California at Los Angeles (UCLA) professor of neurology, and lead author Cyrus A. Raji, a medical student at the University of Pittsburgh School of Medicine, compared the brains of people who were obese, overweight, and of normal weight. To define the weight categories, the scientists used the Body Mass Index (BMI), to establish that normal weight people had a BMI between 18.5 and 25, overweight people had a BMI between 25 and 30, and obese people's BMI was more than 30.
The scientists wanted to document whether the brains of those in each of the three groups were equally normal and healthy. Surprisingly, they weren't. In fact, the scientists discovered that obese people had eight percent less brain tissue than people with normal weight. In addition, people who were only overweight and not downright obese still showed a loss of about four percent of brain tissue.
Thompson, who is a member of UCLA's Laboratory of Neuro Imaging, said in a statement to the media that this study marks the first time anyone has established a link between being being overweight and having what Thompson called in a statement to the media "severe brain degeneration." In fact, he noted that "..the brains of obese people looked 16 years older than the brains of those who were lean, and in overweight people looked eight years older."
"That's a big loss of tissue and it depletes your cognitive reserves, putting you at much greater risk of Alzheimer's and other diseases that attack the brain," Thompson stated. "But you can greatly reduce your risk for Alzheimer's, if you can eat healthily and keep your weight under control."
The researchers used brain images from the earlier Cardiovascular Health Study Cognition Study. The researchers then transformed those scans into three-dimensional images using a high tech neuroimaging method that produces detailed resolution mapping of differences in brain anatomy.
When they compared both grey matter and white matter of the brain, the scientists found that the people defined as obese had lost brain tissue in the frontal and temporal lobes (parts of the brain critical for memory and planning), the anterior cingulate gyrus (needed for attention and executive functions), hippocampus (critical for long term memory) and the basal ganglia (needed for movement). Overweight people showed less brain loss, but it was brain loss, all the same -- mostly in the basal ganglia and the parietal lobe (known as the sensory lobe).
"It seems that along with increased risk for health problems such as type 2 diabetes and heart disease, obesity is bad for your brain: we have linked it to shrinkage of brain areas that are also targeted by Alzheimer's," Raji said in a statement to the press. "But that could mean exercising, eating right and keeping weight under control can maintain brain health with aging and potentially lower the risk for Alzheimer's and other dementias."