Dr. Sanjay Gupta: The buzz is hunger hormone

CNN's Dr. Sanjay Gupta

(CNN) -- Now that researchers believe they have discovered a hormone that tells the body when it's hungry, will this emerge as a new, effective, serious weight loss tool? CNN's Dr. Sanjay Gupta tackled the subject on American Morning with Paula Zahn.

ZAHN: So, doctor, is this the panacea that everybody's looking for.

GUPTA: Well, we don't know yet, but it's certainly a tool in the battle against the bulge, as you say, the battle of the bulge being a big one. Sixty percent of this country's adults are overweight and 15 percent of the children -- and a lot of scientists are looking at different ways to try to curb appetite.

Scientists in England have come up with a new way -- possibly. It's not out there yet. Let me tell what you they're thinking. They basically found that in mice, first of all, a certain hormone is released after you feel full, after you've eaten.

They actually took that hormone and started injecting it before a meal was given, and found that the mice did not eat after that. They decided to try that in human volunteers, 12 volunteers, to be specific, in England, and what they did was interesting -- they injected half of them with the hormone, and half of them they just gave a placebo, and then they put them in front of a big buffet.

What they found was that people who received the hormone ate a third less than they would have normally eaten compared with the other people. .. They described [their hunger] as being 40 percent less with this hormone being injected before the buffet.

So that's sort of where the impetus -- that's what we're talking about. It's still very much in the early stages, but this hormone called PYY-36 is all the buzz right now.

ZAHN: So is it safe for everyone?

GUPTA: Well, we don't really know how safe it is, and that's probably why they're going to do clinical trials. But let me give you a sort of idea of exactly how it works, and maybe it makes a little bit more sense.

We have an animation that basically describes this. If someone takes some food normally, you see the food going down into the stomach and then into the intestines. As it's going through the intestines, certain things happen. Cells within the intestines start to aggregate, and then they release a certain hormone, this hormone PYY 36. This hormone eventually finds its way into the bloodstream, and through the bloodstream, goes back up to the brain.

There's an area in the brain that is responsible for your feeling of fullness. This hormone makes its way all the way up to that area, gets to that area of the brain ... and stimulates it. This area of the brain sends signals, saying, you know, it's full, no need to eat anymore, and you get a feeling of fullness ...

Now it's hard to say whether it's safe, Paula, to answer your question. It's still very much in the early stages. But it does look promising right now.

ZAHN: So I guess most of us have never given our brains much credit for telling us we are full. We always rely on our tummy to tell us that. Let's talk a little bit about other appetite suppressants. Is this at all similar to those mechanisms that have been used before?

GUPTA: It's not different from a couple of other products that are out there that also rely on the center of the brain to feel full. I should also point out one thing, Paula, as well. It takes a while for that signal, as you can see there in that animation, to get back up to the brain, and that's important, because people who eat really fast won't feel full until they've eaten a lot of food, whereas people who eat more slowly may eat a lot less food and still have the same feeling of fullness, because of that delay in the signal getting from the intestine to the brain. But there are substances out there that actually do affect the brain as well.

The thing that's promising about this is that it seems to be so specific to this particular area part of the brain, so the side-effect profile may be much lower.

ZAHN: So you sound pretty hopeful that ultimately this treatment could be used for people really struggling with losing weight.

GUPTA: Yes, I'm going to stay a little guarded on this one still, Paula. Hunger mechanisms are a very complicated things. I think that this is a step in the right direction, but you have to look at blood glucose levels, you've got to look at overall obesity levels. Fat people, people who are obese, might actually have more of this hormone already. Do they need more? I think a lot of study needs to be done, but I think it's a step in the right direction.

ZAHN: The most wise thing you talked about is the speed in which we at. Why don't you come spend dinner at our house, and see if you can get us to sit more than 15 minutes at the dinner table together?

GUPTA: Do you actually sit when you're eating?

ZAHN: No, we do. We're good. We sit, maybe 14, 15 minutes, and then the kids split. So we all could eat a little bit slower, couldn't we?

GUPTA: That's right, I think that's a good idea.