A nutritionist weighs in.


If you’re as obsessed with Halle Berry as we are, you probably already know that she swears by the ketogenic diet. The 51-year-old actress has been open about using this high-fat, moderate-protein, low-carb eating plan to manage both her weight and her type 2 diabetes.

But on the latest installment of her #FitnessFriday Instagram Stories, Berry revealed that in addition to eating keto, she also practices intermittent fasting.

“I normally eat two meals a day,” Berry told viewers. “I normally skip breakfast and I sort of fast and I do my green drink or I do my bullet coffee,” she added.

Intermittent fasting is one weight-loss and healthy-eating strategy that doesn’t have a strict rule book. Some people eat only during a specific time window every day, while others restrict their diet for an entire 24 hours a few times each week.

Fasting in general isn't a smart idea, but intermittent fasting appears to have some upsides. Periodic fasting has been linked to a lower risk of heart disease, diabetes, and cancer, and it may help slow down aging. It’s also been shown to improve cholesterol levels and stabilize blood sugar, as well as help with weight loss.

Considering those benefits, it’s no surprise Berry is a fan. But is it safe to practice intermittent fasting and the keto diet at the same time?

“Technically there is no reason intermittent fasting and keto can't be combined,” says Health contributing nutrition editor Cynthia Sass, MPH, RD. “Because a keto diet tends to reduce hunger, many people feel it’s easier to stick with intermittent fasting when following a keto plan.” Not much research exists, however, on the effectiveness of pairing the two approaches, Sass adds.

If you’re thinking of trying intermittent fasting, you’ll only see results if the food you do eat is healthy. “Simply eating a high-fat diet on a time-restricted schedule can lead to nutrient shortfalls that can negatively impact your health,” says Sass, “even if you're losing weight simultaneously.”

Sass also emphasizes that intermittent fasting and the keto diet, separate or together, are not right for everyone. “Intermittent fasting and keto are both big commitments that will impact your social life, and for many people are not sustainable long term.”

Both eating plans involve significant lifestyle changes that can become overwhelming. “If a method of losing weight feels like a struggle and does not make you feel well both physically and emotionally, it's not right for you, no matter how popular it is,” Sass says.

Though we can all agree intermittent fasting and the keto diet seem to be working for Berry, it’s important to remember our bodies are uniquely ours and might not have the same needs as someone else’s.