Transcript for '21-Day Belly Fix' Claims Digestive Health Is Key to Weight Loss
Up next, the surprising way to jump-start the weight loss right now without going on a diet? It all begins in your belly. The secrets are revealed in a brand-new book that's out this week. "The 21-day belly fix." Reporter: It's the diet plan promming a slimmer waist. But it doesn't involve tiny portions or grueling workouts. This fix is all about focusing on the bacteria in your belly. Your gut, or your belly is the command center for just about everything else that happens in the body. Reporter: Dr. Tas wrote "The 21-day belly fix." She says digestive health derms everything. If you have the wrong mix or the wrong population living if your belly, it affects your metabolic rate. Reporter: Her plan for weight loss, fo loss, four phases over three weeks. Phase one, detoxification. On the menu, apple cider vinegar and green tea to aid digestion. Green juice and protein shake for energy. Then more foods are gradually added back in the last three phrases. Rest, rebuilding, and finally an educational phase. Nothing else I tried was getting me any progress. Reporter: Ally says she just couldn't shake those last ten pounds. Until she tried the 21-day belly fix. This whole plan, kind of realizes how your body reacts to certain things. What to stay away from. What I'm okay with. Reporter: Not everyone is convinced. Do we know enough about what's happening in the gut to make definitive statements about how it could influence weight loss or other systems? I don't think we can. There's a lot of research. We don't yet know the direction it's going to take. Reporter: But for Dr. Tas, the secret to slim is all about trusting your gut. You have to fix your belly to find your health. Reporter: For "Good morning America," Mara schiavocampo, ABC news, New York. Joining us sen ior medical contributor Dr. Skren Jennifer Ashton. Think about this. This is a hot area. This is the premise of the probiotic trend. We have good evidence from mice and humans that there is chronic low level inflammation produced by the bacteria in our G.I. Tract that can start and promote obesity. We know that. Does a diet or changing your food actually change those bacteria in the short term or the long term? We don't know. Based on what we do know, somewhat the key to making this work. This diet will 100% work. It's low in carbs, fat, in the short term, it will be effective. We don't know long term whether you can actually change the DNA in those trillions and trillions of bacteria that occupy our G.I. Tract. It sounds like we're trying. Like it's worth trying. Should anybody not? Pregnant women? A chronic G.I. Issue. For someone who wants to initiate a kind of new page, absolutely. Any red flags to look out for? I have a problem with the phase cleanse or detox. Our G.I. Tract does it pretty well on a daily basis. Thank you. There you go. I thought as much. Jen, thank you very much. And Dr. Ashton will be taking your questions on Twitter throughout the morning. Tweet her @drjashton. We have a fabulous upgrade
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