Here's a prediction: It's only a matter of time before people start zapping their brain to shed weight.
In the last few years, electrical brain stimulation (transcranial direct current stimulation or tDCS) has become a hot topic. The principle behind this area of research is that a small electric current, delivered through electrodes attached to the head, can increase or decrease the activity of the brain for several minutes. The initial results are promising: Such treatment has been shown to help train pilots faster, make math calculations easier and even aid in the rehabilitation of stroke patients. The currents tested are a tiny fraction of those used for electroconvulsive therapy (a proven therapy for severe depression, a brutal version of which was memorably portrayed in One Flew Over the Cuckoo's Nest) -- just 1 to 2 milliamps, less than what's needed to light a typical LED. Although exciting and plausible, the researchers in the field freely admit these are early days, and both the efficacy and long-term safety are yet unknown.
Can this method also address our oh-so-tough and ever-persistent weight control problem? A few small studies suggest that tDCS can diminish feelings of hunger and reduce craving for sweetness, and now a German group published a new study in The American Journal of Clinical Nutrition that shows this method can make people eat less.
Shocked into reduced appetite
In the new study, 14 healthy-weight male students were alternated between 20-minute treatments with either electric stimulation or sham stimulation for eight consecutive days -- the electric and sham treatment assignment was known to the researchers, but was easily confused by the students as the zap is so mild. The area stimulated was in the prefrontal cortex, thought to modulate our behavior around food. While the volunteers thought what was tested was their mood, what was actually checked was how much they ate at a subsequent buffet.
The response to the repetitive electric treatment was about 14 percent reduction in food intake by day 8 of the experiment, compared to the sham treatment, and the diminished eating was mainly of carbs. The short treatment didn't lead to weight loss.
The $20 slimming cap?
Commercial companies have jumped into the improved-mental-performance arena with devices that they claim increase the plasticity of your brain and make your synapses fire faster -- they admit these devices are not FDA approved or proven to cure disease. For the handy, there's no need to shell out hundreds of dollars: The components needed -- a battery, a resistor, a few wires, sponges etc. -- are available and cheap, and devising a DIY kit isn't that difficult. YouTube has many tutorials.
And although none of us would mind a bit of cognitive enhancement, the humongous diet industry proves we're absolute suckers for half-baked, magic weight loss solutions. Just a hint of weight loss success unleashes a tide of demand, and I won't be surprised if those in possession of electrodes will now be searching for that elusive dorsolateral prefrontal cortex that supposedly controls our food cravings and appetite.
Hence my prediction.
But not only is this method far from proven for any condition yet, it also isn't necessarily harmless. Here are a few words of caution: Google hasn't yet mapped the brain for DIY navigation, and even researchers with MRI and EEG machines can't neatly pinpoint to the area they want to treat, so we might be awakening anger rather than self control; 2 milliamps may seem harmless, and we can agree that that amount of juice won't drill a hole in your skull, or make neurons fire, but the currents that transmit information within human cells are even smaller, and just ask yourself this: If you believe 2 milliamps are enough for a positive effect, then why shouldn't they suffice for nasty side effects?
There'll also, no doubt, be those who think -- following the prevailing logic regarding vitamins -- that if 2 milliamps are good, 20 must be better.
The science definitely isn't ready, but if you're itching to try brain stimulation for weight loss in a controlled setting -- and at the same time help advance the knowledge -- the National Institutes of Health is recruiting volunteers for a clinical study.
Dr. Ayala