For decades, the medical community and the government have advised Americans to cut down on fatty foods to avoid heart disease. Now the tide is changing, with some experts recommending more fat and protein, and fewer carbohydrates, to help you stay heart healthy and avoid diabetes.

If you grew up in the 1950s or ‘60s, chances are you ate eggs and bacon for breakfast, steak for dinner, and there was always butter on the kitchen table. Fast forward to the 1980s; you probably switched your diet to include a slew of low-fat products. If you are still clinging to the belief that fatty foods cause heart disease and should be avoided, you may want to think again. So says Dr. Larry Kaskel, a lipidologist and medical director of Northwestern Wellness Center in Libertyville, Ill.

Healthline sat down with Kaskel to find out whether fatty foods are actually beneficial and what Americans should be eating and doing to prevent heart disease, obesity, and diabetes.

Pointing out that for the past 60 years, saturated fat and cholesterol have been linked to heart disease, Kaskel said, “There has been a steady cornucopia of contradictory facts, yet this theory persists because of some scientists’ and doctors’ ambition, greed, and selection bias. When doctors and researchers respond to scientific or technical evidence, it’s usually in ways that justify their preexisting beliefs. They become overly attached to their own hypotheses.”

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Faulting pharmaceutical companies, large agricultural firms, trade associations, and the government for promoting carbohydrates, Kaskel said the result has been an epidemic of obesity and diabetes. “We’re not eating what we should be eating, which is saturated fat and proteins. We really don’t need any carbs in our diet. The human body requires zero carbohydrates to function. It’s nothing new that excessive carbs cause Type 2 diabetes, which is the most prevalent [type of diabetes]. If you restrict carbs and replace them with fat and protein, you can reverse and cure diabetes, and you don’t even need to be on medications,” said Kaskel.

Consumers are confused, Kaskel said, because “they believe the lie. They are still afraid of fat. They don’t know what to do. They are paralyzed by all the data out there. They think, well, I’ve been told fat is bad for me, so I can’t eat fat. What’s left? Carbs.”

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According to Kaskel, all cereals are unhealthy, even oatmeal, which he says can spike your blood sugar levels. “Our breakfast should be like any other meal we eat, which is one of fat, protein, and minimal carbs. You can have an omelet with veggies, a piece of chicken, or roast beef with veggies,” he said.

People who aren’t obese should eat what they want, said Kaskel, but he suggested that obese people should switch their diet to one that is predominantly fat and protein in order to lose weight. “It’s the carb that drives the weight gain. Whenever you eat a carb, your body releases a hormone called insulin. Insulin tells your body to store whatever came in as fat. Lock it away; don’t access it. As long as you keep eating carbs, you will release insulin; you will store it as fat. Once you stop eating carbs, your body will start burning your fat stores and you will lose weight,” he said.

Kaskel went on to say that Americans need to be reprogrammed. “We need to reboot them and get them out of this cult mentality that fat is bad for them, and tell them their grandparents and great grandparents were eating butter, bacon, eggs, and lard, and they weren’t dying from heart disease. They weren’t obese and they weren’t diabetic.

Moderation is key with everything in life. We don’t know how to moderate in this country. We’re very extremist. When anything says low fat, the fat is replaced with more carbohydrates so you are basically screwing up everybody by eating low-fat,” Kaskel said. “There is no reason to pick low-fat foods. The only reason people do that is they think if they eat fat they will get fat, but that is incorrect.”

Emphasizing that a safe amount of carbs is the least amount that you need, Kaskel noted that some doctors say if you do a heavy workout you can have some carbs after the exercise. But, he added, “Otherwise you shouldn’t really be eating carbs. A safe amount, in my opinion, is less than 75 grams a day, which comes out to 19 teaspoons a day, which is still an enormous amount of sugar.”

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Kaskel recommended a diet in which 60 percent of calories come from fat, 20 percent from protein, and 20 percent from carbs. If you are diabetic or obese, he advises 60 percent from fat, 35 percent from protein, and five percent from carbs. “Again, use moderation,” he said. “Butter is not the enemy. Fat is not the enemy. Saturated fat is not the enemy.”

If you do drink alcohol, do so in moderation, said Kaskel. In addition to drinking causing problems at home and at work, he cautioned that wine contains a lot of sugar. “You will have to cut back on the other carbs if you want to stay thin,” he advised.

Kaskel went on to say that exercise alone isn’t going to make you lose weight. “You’d have to be extremely excessive and extreme in your exercise, which I don’t think is healthy. A healthy amount is 15 minutes a day of doing something where you break a sweat,” he said.

Kaskel concluded, “We’ve had it backwards for 50 years – telling people to eat low fat when we really should have been saying eat low carb. We’re almost at the point where the tide is changing. People should start looking at food labels for the amount of sugar and stop focusing on the fat content. If you look at the carbohydrates and try to keep your carb levels below 75 grams a day, you should not get obese; and if you are obese, you will lose weight, you’ll be able to reverse your diabetes, and get off of many of your medications.”

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