to the hot, new diet trend and why avoiding your bathroom scale would actually help you drop the weight. As much as 15 pounds, they say, in 30 days. ABC's juju Chang has the story. Reporter: It's the... See More
to the hot, new diet trend and why avoiding your bathroom scale would actually help you drop the weight. As much as 15 pounds, they say, in 30 days. ABC's juju Chang has the story. Reporter: It's the hottest new trend for shedding those extra L B's fast. The whole30 diet. Po filed in the best-selling book, it starts with food. The brainchild of certified sports nutritionist Dallas and Melissa Hartwig. The whole30 aimed at resetting your body's reaction to food. For 30 days they only eat fruit, vegetables and protein, no grains like rice or wheat. No beans, no soy, no dairy and, of course, no processed sugar or alcohol. But one surprising no-no, the bathroom scale. So many people are so obsessed with that number on the scale. The scale will blind you to all of the improvements you're seeing in your medical condition. Reporter: But the key to the diet is the slow reintroduction of foods to see how your body reacts to gluten, or dairy or sugar. 30-year-old Ashley reeves is a fan. Like many moms whose world reinvolves around her kids she says she didn't have the time or energy to get back into shape. I had done a few healthy eating things and I just wasn't losing the baby weight and I was getting pretty frustrated. Reporter: Last year she dropped 15 pounds in the first whole 30 days without working out. The first week I'd say is really rough because your body is kind of like purging all these things you've been eating for years but more than anything, my results are measured in energy. I felt amazing. Reporter: More recently Ashley tried the diet again shedding another 10 pounds. She says effortlessly but some dietitians have their concerns. When you start eliminating food groups like dairy, legumes and whole grapes you miss out on calcium and vitamin D. Reporter: But for whole30 dieters like Ashley glad to have found a new relationship with food the results she says can be life-changing. We all know it's not about losing the weight. It's about keeping it off and nutritionists warn the risk is very high of just gaping awe the weight back once the foods are reintroduced but the point of the 30 days is to learn about how your body interacts with the food and so when you reintroduce dayry or meats or whatever, then you get to see what works for you and create a plan. Right. Okay. Maybe reintroduce them one at a time to see which ones work. Are you reacting to gluten, dairy. What is it your body works with. Coming up our biggest and
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