Kourtney Kardashian said her doctor put her on the keto diet to cleanse her of toxins and metals. Experts say there's no evidence that works.

• Kourtney Kardashian is back on the low-carb, high-fat keto diet, according to her lifestyle website Poosh.
• Some fans and critics, however, expressed concern that the diet is unhealthy, noting that Kardashian is not a dietitian and doesn't have a background in nutrition.
• Kardashian responded to fans on Instagram that her keto diet is doctor-approved, and that she uses it for brief periods to "help detox metals or toxins."
• There's no evidence that keto or any or diet can help one "detox," from metals or anything else. In fact, your liver and kidneys take care of all your detoxing needs naturally.

Summer is here, the weather is warming, and Kourtney Kardashian is back on the keto diet, according to the celeb's lifestyle blog Poosh.

Kardashian says the high-fat, low-carb eating plan is approved by her doctor to "to help detox from metals and other toxins."

She was trying to diet, she said, because "I want to look and feel my best."

Although she suggested consulting a doctor before trying this (or any) diet, the post incited criticism that the keto diet may be unhealthy, and that Kardashian does not have the qualifications to offer nutritional advice.

While there are some medical applications of the keto diet, experts say there's no evidence that it can "detox" anything.

Kardashian's keto diet cuts out grains, root vegetables, and all fruit except berries

The ketogenic diet, or "keto" for short, entails eating a higher percentage of dietary fat and very few carbohydrates to induce a state called "ketosis" where the body burns fat for instead of glucose, its preferred fuel source generated from carbohydrates.

"I personally love it" Kardashian said of keto. The celeb spent two months on the keto diet in 2018, and wrote on Poosh that it was "a really positive experience," although it can be very restrictive even compared to other diets.

Although keto diets can vary widely, a common version limits your daily carbohydrates to between 5-10% of your overall calories, and sometimes fewer than 50 grams of carbohydrates per day. For reference, a medium-sized apple has about 25 grams of carbohydrates.

Kardashian wrote that her keto diet cuts out sugar, grains, beans, root vegetables, processed foods, alcohol, and all fruit except small portions of berries.

The health effects of the keto diet have been hotly debated, with some nutritionists and cardiologists objecting to the high saturated fat of many keto diets, and others arguing that the restrictiveness of the diet can make it difficult to sustain long-term.

Keto advocates, however, praise the diet's effectiveness for weight loss, its value for treating health conditions such as diabetes, and its potential for helping steer people away from the standard American diet high in sugar and processed foods.

During Kardashian's first stint on the keto diet, she also noted that she was using the eating plan to detox, claiming that her doctor had found "high levels of metals like mercury and lead" in her body.

There's no evidence keto can help detox anything, metals included

It is possible to have unsafe levels of heavy metal if you're exposed to them in your environment — for instance, you might encounter lead in old paint, and mercury in certain types of fish. These can be dangerous, but there's no evidence that keto can help, according to experts.

"I can't think of any biochemical pathway through which a ketogenic diet would decrease levels of lead and mercury," Andy Belatti, a registered dietician-nutritionist.

A well-formulated keto diet, rich in whole foods, could potentially have health benefits from cutting out processed foods and added sugars, according Dr. Mark Cucuzzella, a professor at West Virginia University School of Medicine and a marathon runner who has published several studies on keto and diabetes.

But, Cucuzzella added, there's no research showing keto has a beneficial effect with regard to heavy metals or any other "toxins."

Furthermore, it's actually unnecessary to seek out a diet plan to detox, since your body is naturally equipped with all the tools it needs.

"We each have a liver and kidneys to do that job without needing a detox diet that is, in most cases, inadequately balanced and lacking in so many important nutrients," registered dietitian Bonnie Taub-Dix, author of "Read It Before You Eat It: Taking You from Label to Table," previously told Insider.

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