Transcript for Could the trendy alternate-day fasting diet be putting you in danger?
Thank you, Paula and Jen. We will talk about the effectiveness of alternate day fasting. Does this trendy diet really help you lose weight long term? ABC's Mara schiavocampo is here with a closer look. Mara, good morning. Reporter: On the surface it sounds great. Diet every other day then eat pretty much whatever you want on N nondiet days but does it actually work any better than good old-fashioned calorie cutting and is it something you can actually stick with? It's quickly become a top choice for weight loss. Now let's talk about the new diet craze. Watch what you eat two days a week and eat what you want the rest of the week. Reporter: A diet many swear by. New research is doubting its effectiveness. Does fasting one day and then eating pretty much whatever you want the next day really work? Simply not sustainable and it's also confusing because it can put you at risk of actually overeating on the days when you're able to, quote/unquote feast. Reporter: On fasting days you eat about 25% of your Normal caloric intake. For someone on a 1600 calorie diet, that's just 400 calories for the entire day. What does that look like? Three ounces of grilled chicken, five almonds, a small apple and half a cup of Greek yogurt. For 34-year-old Alicia, it was a great jump start to weight loss. She lost 31 pounds in ten months from eating just 500 calories two days a week and Alicia says for her it was easy to maintain. I love that I could still eat pretty much anything I wanted on the nonfasting days so, you know, it was a small price to pay for still getting to eat cookies and drink beer and like have burgers and bread. Reporter: But a recent study compares those on an alternate day fasting diet with those who simply cut their calories every day. The result, both groups lost approximately the same amount of weight. So as long as you are reducing your food intake it really doesn't matter what the pattern of calorie restriction is. You'll lose weight. Reporter: The study also found that the alternate day fasting group had a higher dropout rate. Some arguing it's a tough diet to maintain long term. I decided to take a bike ride or a walk through the park or walk home, I would be really hungry and tempted to eat a lot more than what was allotted for that day. Reporter: Now the study also found that alternate day fasting didn't offer any added protection against heart disease compared to those who just cut their calories across the board. Now, the biggest issue is sticking with it. That's one of the biggest challenges. Experts say alternate day fasting is best for those who only eat a few types a day. Really hard for those who snack or graze a lot. Going long stretches without food will be tough. Sticking with it is the hardest part often of new habit formaths. Consistency is key. If you stick with it you'll be okay. Good luck to me. Ginger, what's going on with
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