Experts say it's because its legions of fans are focusing on the short-term benefits of fast weight loss, without factoring in possible long-term risks. Katz's low opinion of keto is echoed by many nutritional specialists across the country. Katz joined 24 other top names in the field to rank 35 popular weight loss programs for 2020 recently put out by U.S. Katz is no fan of keto, or any other diet that restricts entire food groups, calling them unhealthy and unsustainable.
As always, be sure to consult your doctor before making any dietary changes. With that said, he says, there are alternative fuels -- like something called ketone bodies. “You might find that you fatigue more quickly or that exercise seems harder than normal,” says Seattle-based nutritionist and Academy of Nutrition and Dietetics spokesperson Ginger Hultin, MS, RDN. Behavioral trials with more powerful interventions lasting ≥1–2 y, and feeding studies of ≥4 wk, will be needed to test the true efficacy of carbohydrate restriction and clarify mechanisms.
If you want to lose weight, cut down on your fat intake by calories, or grams. A ketogenic diet consists of replacing carbohydrates with fats. It is a very low-carb, high-fat diet that shares many similarities with the Atkins diet. The reduction in carbs puts the body into a metabolic state called ketosis.