Is it possible that everything we have long held as dietary gospel is backwards? Tonight you will learn a mom/investigative reporter who says all of those high-fat foods we have been told to avoid are... See More
Is it possible that everything we have long held as dietary gospel is backwards? Tonight you will learn a mom/investigative reporter who says all of those high-fat foods we have been told to avoid are actually good for us, not only that, she says if you eat things like cheeseburgers, meatballs, and bacon, all my favorite foods, you may actually lose weight. Here is my "Nightline" co-anchor juju Chang. ? Reporter: It is an age-old debate, low carbs? Or low fat? Some dieters like gwenyth paltrow, and Kim Kardashian advocate Atkins to lose the pounds. Some suggest Kim Kardashian could be on to something. You can still have the body without putting down the bacon. But the food revolution isn't just being waged by celebrities on the red carpet. We don't have any low fat foods in our fridge. Reporter: But also by this unassuming New York City mom. We have heavy cream, half and half, whole milk, we don't have low fat milk. Reporter: Nina is author of "Big fat surprise." The surprise is that saturated fat is really not bad for health. It does not cause heart disease. Thank you. Reporter: She is not a scientist, but she is on a mission to literally turn everything we know about nutritional guidelines on its head. Mine family we basically eat the usda food pyramid turned upside down. They have meat at the top. We would put them closer at the bigger slab on the bottom. So we want to lunch with her at a carnivore's delight, strip house steakhouse in New York. She spent the decade analyzing revered traditional and medical data to prove a radical idea. That fat may not be the devil we have been taught it is. When you take in carbohydrates your body does something come letly different than what it does when you take in protein or fat. It trigger the release of insulin, insulin is the king of all hormones for storing fat. You are saying my body reacts better to bacon than a bagel? Exactly. Reporter: How is it saturated fats became demonized. The story begins in the 1950s when the nation was terrified of the heart disease epidemic. The chief killer of Americans is cardiovascular disease. Reporter: The founding father of the low fat diet produced a landmark study to see what might cause heart disease. He examined 13,000 subjegts. But only looked at the diets of a few hundred men. That study set the government on its path to recommending a low-fat diet in order to prevent heart disease. A lot of people are faithfully following the dietary guidelines. We have changed the obesity rates keep climbing. It tells you our working high pohigh -- hypothesis isworking. Reporter: As a carnivore, she says she lost 10 pounds 2001 trying. What does make you fat? The best science that we have so far points to carbohydrates. If your diet ties high in carbohydrates, regardless of the kind that they are, it's harder for you to lose weight and you are at higher risk for heart disease and diabetes. Many scientists are beginning to agree as does our waiter. What is your reaction to the fact that steaks may be good for you? It is great. We have known it for years here. Reporter: Not everyone thinks we should throw out the low fat guidelines. I don't think it is enough to look at existing studies we have and say they're not perfect. That's not an indicator to go out and say sure let's eat more saturated fat. I think nutrition it is very difficult to get perfection. But I think where we are at, we have enough suggestive evidence to say -- you know what? Eating a lot of saturated fat may not be the best idea. It's one thing to say, okay. Saturated fat may be bad for you. Is it responsible to say well let's stock up on high fat foods? The last decade of rigorous clinical trials and long term trials of two years really definitively showed that a high fat diet is better than a low fat diet. Other experts say the trials are far from definitive. While the results show that high fat diets may not be harmful, they're not necessarily protective either. But that isn't stopping her, she is even changing the rules at home for her two young boys. So a typical breakfast is bacon, or eggs, sausage, meatballs, sometimes. Do you get sick of meatballs and sausage? No. Reporter: Do you wish you had cereal instead? You probably don't know what cereal is. Reporter: She says she snacks all day. Mostly on cheese. Nuts and protein. I can eat red meat three times a day. I could have a cheeseburger for lunch. Think nothing of having a cheeseburger for dinner. I don't think that's killing me. Reporter: Or is it? When we learned she didn't know her cholesterol levels, we asked if she would be willing to find out. Hi, I'm here to see the doctor. Reporter: She got tested off camera. The first door on the right. Reporter: Now her doctor is about to tell her the full results. What's the overall verdict? Unless you have a very strong family history of premature heart disease, this looks fabulous. You are good. It is very, very low. These are good Numbers. Yea! Reporter: The self-appointed Guinea pig is clearly relieved. So I should just keep doing what I am doing, right? Whatever I am doing. However bizarre it sounds? In my judgment. Whatever you are doing is working for you. Reporter: Like many physicians, the doctor remains cautious about going overboard on a high-fat diet. I couldn't say that eating in this fashion is appropriate for everybody. Clearly if you do eat in this fashion, you probably should be checked by your physician at some point. That feels great. I am going to celebrate with a steak tonight. Reporter: For "Nightline," juju Chang in New York. Our thanks to juju Chang. The "Big fat surprise" is at
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