Many factors can cause obesity, including genes, lifestyle and environment. But there's some evidence to suggest that quirks of the brain might be a factor, too. In fact, doctors may be able to stimulate the brain so that patients lose weight, according to a study published today in the journal Obesity and led by researchers from the National Institutes of Health.
The idea that obesity can be controlled with the brain shouldn't be that surprising—everything from appetite and cravings to self-control is funneled through the brain, even if the signals are coming from the stomach. Past studies have shown that obese people have less activity than lean people in a particular region of the prefrontal cortex, the part of the brain responsible for behavioral planning and making decisions. That suggests that people who are obese might have trouble quieting signals that come from more primal parts of the brain that tell them to keep eating, even if they want to lose weight.
The researchers thought that if they could stimulate the brains of obese patients, maybe they would be able to lose weight. The researchers chose nine obese patients who were each staying at the facility for two eight-day stints. On the first visit, patients were all given sham transcranial direct current stimulation (tDCS), a method in which low-amplitude current is sent to the brain through electrodes stuck to the scalp—in the sham version, patients are hooked up to the machine but no electricity comes out. But during the last three days of the second visit, five patients were given active tDCS, and the other four were again given sham tDCS. Then, all patients were allowed to go to the vending machine and pick whatever food or drink they wanted. The researchers found that the patients who received active tDCS consumed an average of 700 fewer calories than they had during their first hospital stay, and lost an average of 0.8 pounds.
To the researchers, these results provide an early indication that tDCS might help obese patients lose weight. And though this is a small study with only modest results in weight loss, officials are desperately looking for new treatments and solutions as reports estimate that the United States is spending billions of dollars per year on treating obese patients.
Scientists still have a lot of questions about how obesity affects the brain's function. Next, the researchers plan to more directly compare patients who receive tDCS and those who do not to better understand the treatment's effectiveness and safety.