Celebrities are obsessed with the 80/20 diet - but an expert says they're making it 'too restrictive'

A long list of celebrities follow the 80/20 diet, from supermodels Miranda Kerr and Gisele Bundchen to football star Tom Brady and actresses Olivia Munn and Kate Bosworth.

In theory, the 80/20 diet doesn't sound too complicated. It's about eating healthy, well-balanced foods 80% of the time, while allowing yourself to indulge in "cheat" foods the remaining 20% of the time, according to registered dietitian Rachel Berman, head of content at Verywell.com.

It's a diet that people can apply to their everyday life, even thinking of the 20% as "dessert" at the end of the day.

But, celebrities have taken the diet one step further - making it far more restrictive than it actually needs to be, the dietitian told INSIDER.

Celebrities are being really strict about their 80/20 diets.

Munn recently told Women's Health that she eats only fruits and vegetables 80% of the time, with the remaining 20% reserved for "any kind of meats or breads or anything else."

Likewise, Bundchen and Brady follow an "80/20 raw diet, with big colorful salads and lots of fresh veggies" even when on vacation, their chef Joanne Gerrard Young told Well and Good.

Meanwhile, Kerr recently told Yahoo that she tries to eat organic foods 80% of the time and Bosworth revealed to Self that she follows a mostly "wheat-free, sugar-free, dairy-free meal plan" 80% of the time.

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Olivia Munn

But that's not sustainable for the rest of us.

Berman told INSIDER that, by and large, the 80/20 model is a great diet to follow, particularly since it isn't so "black and white" that it prohibits people from eating a half a cup of ice cream here, having a glass of wine there.

However, the restrictive 80/20 diets that celebrities are following seems "a little unbalanced" to the dietitian.

"That seems a little too restrictive. That's not the type of 80/20 that is sustainable. If you do it right, by having a healthy balance at each meal and considering the 20% to be food that maybe isn't as nutritious, that way it's more sustainable in the long run," Berman said.

Rather than trying to replicate the strict diets of those celebrities, Berman recommends people just stick to healthy, fiber-rich foods as much as they can 80% of the time.

"That way it's less about a 'fad diet of the moment' but more about 'hey, this is how I can really eat and enjoy all the foods that I love for life,'" she said.