Everything Fit Women Need to Know About the Keto Diet

Why the nearly 100-year-old keto diet is finding some modern-day love.

Oil Bubbles
Joseph Clark / Getty

Joseph Clark / Getty

Keep It Short (and Unsweetened)

Yet, if weight loss is your ultimate goal, some experts say keto is best kept for its original use. “It might help decrease the severity and incidence of seizures in epileptics resistant to medication, but for fat loss there are better options,” says Marie Spano, M.S., R.D., C.S.C.S., C.S.S.D., a sports nutritionist for the Atlanta Braves, Atlanta Hawks, and Atlanta Falcons. Burning fat may produce more ATP (the molecule that powers you during activity), but during high-intensity exercise the body cannot produce ATP fast enough from fat to meet its energy demands, and your intensity will slow down, she explains. And some experts say there’s nothing magical about the ketogenic diet for weight loss. “Just because you’re burning ketones does not mean you’ll lose weight,” Spano adds.

Roberts agrees that keto is not a diet she recommends for the long term. “Women, especially those who exercise regularly, tend to do better with more carbs from both a health and performance standpoint. Our hormones are more sensitive than men’s, and when you top off exercise and life stressors, with a very low-carb, ketogenic diet, it’s often a recipe for burnout,” she explains.

In fact, many of us simply can’t stay on a keto diet for too long. “The ketogenic diet is not sustainable for the majority of people, and it can be difficult to go on and off the diet easily,” says Spano. That could be partially due to the time it takes for the body to become fat adapted and start utilizing ketones, which for some can take several weeks. This stage is sometimes referred to as the “keto flu” (or carb flu) and simply is a sort of sugar/carbohydrate withdrawal phase that can be marked by fatigue, nausea, dizziness, brain fog, trouble sleeping, and stomach irritability. “It’s also not ideal for muscle gain, as the carb cutting interferes with the muscle-growth-signaling processes,” Spano says.

And to restrict something—carbs, calories, etc.—for too long and abstain from eating it forever is not realistic, Bell says. Instead, he says, “you should go through different time periods where you’re on different diets. If you’re looking for performance, and fat loss isn’t the most important thing, then a low-carb diet [as opposed to a ketogenic, which is very low-carb in comparison] is the way to go. But if your aim is to control body-fat levels and lose body fat, then a ketogenic diet is the way to go. Once your desired amount of weight has been lost, switch from a ketogenic to a low-carb diet.”

See the next page for tips on going keto the right way.

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