Timothy Noakes, M.D., is an emeritus professor in the Division of Exercise Science and Sports Medicine at the University of Cape Town. While his name may not ring a bell here in the U.S., he’s a full-blown celebrity in his native South Africa and one of the most accomplished exercise physiologists on the planet. You can’t walk by a restaurant in Cape Town that doesn’t offer a “Noakes option”—say, an avocado stuffed with breakfast sausage and eggs, or a double cheeseburger with lettuce sans bun—and evidence of his teachings seems to be everywhere, mostly in the form of the nation’s best-known athletes, including ageless golfing legend Gary Player and eight-time Ironman World Champion Paula Newby-Fraser. In fact, Noakes’ celebrity these days is such that he’s even been pulled into South African presidential politics: To echo the country’s papers of record, “Is President Jacob Zuma’s and his wife’s dramatic weight loss a result of the Noakes Diet?” No one is sure about the president, but his wife, definitely: She’s lost 66 pounds following the Noakes plan.
To high-performing athletes, Noakes preaches that the bedrock tenet of endurance athletic nutrition—that winning performance is best fueled by eating lots of carbohydrates—is simply wrong. Instead, he believes athletes can alter their bodies so that their metabolism burns fat as a primary fuel source, a physiological process known as ketosis, either from stored body fat or from the foods they eat every day. For non-athletes and anyone trying to lose weight or keep it off, Noakes’ advice is that eating a high-fat diet, with few if any refined carbs and as little sugar as possible, will switch on the same fat-burning system and keep your body lean and your weight stable without making you hungry. According to Noakes and a growing number of nutritionists, physiologists, and biohackers, when you’re in a state of ketosis—best attained through a strict “ketogenic diet”—good things happen.