You read that right. In a new study out in Nature Neuroscience, scientists tinkered with a single gene in a mouse and made it less likely to get fat. Finally I can eat as many Double Stufs as I want without worrying about gaining weight. If scientists can turn what they've learned into a pill, that is.

How'd the researchers do it? By changing one part of the mouse's brain, the hypothalamus. One of the hypothalamus' many jobs is body weight regulation. So it was a logical place to start.

The scientists couldn't go in with a wrecking ball and tear the hypothalamus apart. It is an important part of the brain with lots of different duties. They needed to something pretty subtle so the mice would survive but be thinner.

What they did was to keep certain cells in the hypothalamus from being able to release a neurotransmitter called GABA. This was enough to make a mouse better able to maintain a lower weight.

This study suggests that GABA's normal job in the hypothalamus is to keep mice (and probably us) from burning too much energy. Makes sense in the wild. But is quite a pain in my cubicle.

Now, we can't go changing human genes (at least not yet). But perhaps scientists can come up with a pill that will do the same thing. A pill that keeps AgRP neurons from releasing GABA in the hypothalamus.

This is as hard as it sounds. But now that scientists know what to do, pharmaceutical companies will be able to apply all of their firepower to solving this problem. Given the potential market, if anyone can find a medicine for restricting weight gain using this finding, they will.

Before I get too excited, though, I want to see what happens to these mice as they age. Burning calories makes free radicals which damages DNA which causes aging and can cause cancer. Perhaps burning more calories this way might generate more free radicals.

Of course even if it does, maybe we could just take the pills with cranberries or some other anti-oxidant. Or maybe Nabisco can make an Oreo laced with antioxidants…

Given today's environment, it is surprising that there are still thin people around.

The origins of this epidemic are pretty easy to spot– lots of food and less opportunity for exercise. And yet, not everyone in the U.S. is overweight. So why is one person fat and the next thin?

One big reason is genetics. A number of twin, family and adoption studies have found that somewhere between 45-60% of body mass index (BMI) comes from the genes we inherit. In other words, some people are more likely to be sucked into a Super-Sized meal because of their genes.

So how might genes affect someone’s chances of succumbing to the mountain of food now available? Lots of ways.

Some people burn energy more slowly than other people. These folks need to eat less to maintain their weight. Not an easy thing to do!

Some people take longer to realize they are full. Others get hungrier more quickly after eating. Still others need more sweets and fat to get enjoyment from their food.

The last example was addressed by a study last year. One of the reasons people eat is that they get a hit of dopamine when they do. The dopamine makes us feel good and once we get it, we feel less inclined to keep eating.

The study found that people with a certain version of the DRD2 gene needed more food to get enough dopamine to stop eating. So they ate more on average.

There are more and more studies finding gene variations just like this one. Finding these gene variations might be useful in creating new medicines to help people eat less by decreasing hunger, burning calories faster, etc.

Knowing about these gene variations might also help doctors identify who is at a greater risk for obesity. These folks can get early help in maintaining their optimal body weight.

Now none of this is an excuse for getting fat (although I wish it was). For the most part, genes that affect our BMI make maintaining a healthy weight harder, not impossible.

But what it also means is that the thin should be a bit nicer to the overweight. Recognize that it might be easier for the thin person to not overeat.

This is not to take away from the thin person's accomplishment. In a world awash in high calorie foods and with work and play involving a lot of sitting, it takes will power not to become overweight. Just remember that it is easier for some people to be thin.

http://www.cdc.gov/nccdphp/dnpa/obesity/trend/maps/index.htm