Topping "The heat index," the surprising new book that says if you're having trouble dropping weight, it may not be your fault. Thinfluenc thinfluencers co-authored by Dan Childs tells you where to... See More
Topping "The heat index," the surprising new book that says if you're having trouble dropping weight, it may not be your fault. Thinfluenc thinfluencers co-authored by Dan Childs tells you where to point the finger of blame. Deborah Roberts is here with that. Reporter: We've all heard genetics plays a part in weight trouble. What about your friend, family and co-workers. According to the latest researchers your personal relationships may be contributing to that battle of the bulge. Who would have guessed that extra weight you're carrying around really isn't all your fault. Turns out friends, family, even your office might be partly to blame. That's the conclusion of new research packaged in a new book called thinfluence. It takes that feeling of guilt away from the individual and really relate it to all of the other factors in our life. Reporter: Cardiologist and awe thundershower maliss's wood -- A teen who wants to be healthy. Yep, maliss's daughter can thank her mom for her love of nutritious food and exercise. I have from the beginning of their lives tried to lead from example. Getting them out in the baby jogger when they were 2 or 3 weeks old. Reporter: All four of her kids are avid runners like mom. You got this, Kira. Nice, honey. Reporter: It's true in my house too. Nicky insists on joining me for a run around the park if he can keep up. Keep going. Keep going. Reporter: But this thinfluence can go the other way. If they eat poorly, guess what happens. You have a 37% higher chance of becoming obese if your spouse is obese and a 57% chance if a close friend is obese. It's all about peer eating habits. Even at the office. Just look what I've found here at "Gma." Pastries, lollipops, somebody even shared their leftover potato chips with us. If our co-workers are actually getting together at lunchtime and going outside and going or a walk or even trying to bring healthier snacks into the office, then that can work to improve our overall health. Reporter: So all is not lost if you're surrounded by unhealthy eaters, you don't have to get rid of your friends or family. Actually you can take the charge and try to instill some healthy eating habits which I why I brought a bowl of fruit. I will take that banana. The cupcakes are always in the office. A lot of carbs. Working as a team and you if sort of agree you need to make the change it can make it easier. Of course, it does. Thank you very much, Deborah. Coming up next on "The heat index" a stirring video shared by millions. A couple's decision to allow
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