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FDA Approves New Weight Loss Pill—Does it Work?

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FDA Approves New Weight Loss Pill—Does it Work?

Jun 27, 2019

Plenity is a new FDA-approved medical device that claims to help lose weight by making you feel full before meals. It is swallowed like a pill and has the potential to help the nearly 40 percent of people in the United States struggling with obesity. But does it actually work? Women' health expert Dr. Kirtly Parker Jones talks about the research behind Plenity and suggests some simple, cheaper ways you can get similar effects.

Image credit: GELESIS, INC.

Episode Transcript

Announcer: Covering all aspects of women's health, this is "The Seven Domains of Women's Health" with Dr. Kirtly Jones on The Scope.

Dr. Jones: Four in 10 women are obese, and over 2 in 10 are overweight. That adds up to 6 in 10 women who are overweight or obese. And many of these women would like to lose some weight. And many of those women have medical problems, such as diabetes, or pre-diabetes, or high blood pressure that would be improved or resolved with weight loss.

Okay, diet and exercise can help with weight loss, and exercise alone doesn't really lead to much weight loss. So the focus of interventions for weight loss is diet. There've been medications approved to decrease appetite. These medications change brain chemistry to decrease interest in eating, but these medications have side effects and some of them are very significant, and the FDA has been very careful about approving new weight loss medications.

Many women who take these medications gain their weight back when they stop them. The alternative is weight loss surgeries that decrease the room in your stomach or decrease the absorption of food in your intestines. This approach has been the most successful for sustained weight loss, but it's expensive and with all surgeries it can be risky.

So what if you feel full before you ate, sort of like weight loss surgery without the surgery? The FDA just unanimously approved a new device for weight loss. The device is a pill with a special compound called Gelesis 100 that absorbs water. If you take these pills 20 to 30 minutes before you eat and drink half a liter of water, which is about two eight-ounce glasses, the compound, which is cellulose, swells up and fills up your stomach so that you aren't too hungry and you can't eat so much. The compound is like those over-the-counter bulk laxatives, a cellulose compound.

Now how well did it work? The GLOW study, that's the name of the study with Gelesis as the G, published in the "Journal of Obesity," was conducted in the U.S. and was sponsored by the manufacturer. About 400 men and women took the active pills or placebo with two eight-ounce glasses of water 20 to 30 minutes before lunch or dinner for six months. The average weight loss for those who took the active pills was about 6% of their body weight, and those who took the placebo pills was the average about 4% of their body weight.

So in a 200 pound person . . . Now of this is for people who are math averse, so I'm doing the numbers for you. The average weight loss was 12 pounds over 6 months in the active group and 8 pounds in the placebo. Now looking more carefully at these results, it appears early on that you could predict who is going to lose weight with the pills and who wasn't. Of course, eating patterns are different person to person. If you get lots of your calories in snacking between meals, and that's such an American thing, taking these pills before meals won't make a difference, because you will have already snacked up your calories in there too late. If you're someone who doesn't really pay attention to how full you are before you eat that second serving of pizza or that dessert, that won't make a difference.

But for those who were losing weight on the active pills in the first several weeks, they were very likely to lose over 10% of their body weight in 6 months, about 20 pounds for a 200 pound person, and that's significant.

And among the participants with pre-diabetes or lifestyle treated type two diabetes, people taking the active pills were 6 times more likely to lose 10% of their baseline weight by the end of the study. And people who are pre-diabetic, or had diabetes that was treated with diet, were more likely to have a significant drop in their fasting glucose and insulin. So these pills helped people with diabetes or pre-diabetes get better control over their sugars.

Now unfortunately, the study didn't differentiate between men and women, and that's outrageous. There's the . . . I got the numbers. They should have done that. Women probably eat differently than men, have different eating and fullness cues, and we're going to need to find out more about that.

Now, one quarter of the participants dropped out in both the active pill group and the placebo group. Now that may be related to how hard it is to eat moderately, one, on a schedule, two, exercise 30 minutes a day, and three, drink water and take pills. All were required of the study, and, of course, there were side effects that were bloating, that only women use and I've never heard a man use, was more common in the active pill than in the placebo. Of course, they didn't call it bloating. They called it fullness or distension. It was noted 11% of the time in active pills and 6% in the placebo group. There you go, take nothing and you get bloated. I don't figure that one out.

Now, tummy side effects were common, 43% in the active pill group and 34% in the placebo, but that's how the pills work. The cellulose, which expands to fill up the stomach breaks down as it passes through the intestines and the large bowel, and it's excreted with bowel movements and so you have more bowel movements.

The product which will be called Plentity, that's kind of a cool name, is termed a device because cellulose is a commonly available chemical in food and in laxatives, but the way it's delivered in these pills makes it unique. It will be marketed in the fall of 2019 and available probably in early 2020.

So how does this help the overweight or obese woman who wants to lose weight? Well, firstly, you have to know your pattern of eating and whether you can change it to eating most of your foods at lunch and dinner and not snacking or drinking those mocha frappuccinos. Keep a log of what you eat and when you eat it so you can figure this out. If you don't want to wait until this new weight loss device is available, you can drink two large glasses of water before lunch or dinner.

In the GLOW study, those drinking water and the placebo also lost weight and water's free. Or you can do what some dietitians have suggested, and that is to eat a large bowl of low-calorie vegetable soup before your regular lunch or dinner. This soup thing is common all over the world and particularly in Asian cultures. This has also been shown to facilitate weight loss in American women.

Or you can buy a bulk laxative like psyllium. Take two doses with two large glasses of water before lunch and dinner. This is much like the strategy of this new weight loss device. It's also been shown to facilitate weight loss. Taking this much new soluble fiber in your diet all at once may have the same side effects as this new device, fullness, and that's the goal, nausea, bloating, more frequent bowel movements, that's also the goal of bulk laxatives, and possibly diarrhea.

We'll be watching to see how this new weight loss product works in American eaters and adolescents as it's introduced into the U.S. In the meantime, eat more fiber, drink your water, and thanks for joining us on The Scope.

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