By Natalie Matthews

People who love the Paleo diet are often quick to dismiss naysayers. (I know because I have, like, eight of these friends, and they're cult-y about it.) But a new study just released this week may give them reason for concern, too.

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The study, published in Cell Metabolism, tracked more than 6,000 adults above the age of 50 for 18 years. Some people were on an animal-protein rich diet like Paleo or Atkins (remember when Atkins was a thing?); some were not. And those who ate the animal-protein heavy diet fared way, way worse than others: They were 74% more likely to die early than those who followed a low-protein diet.

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"We provide convincing evidence that a high-protein diet, particularly if the proteins are derived from animals, is nearly as bad as smoking," said Dr. Valter D. Longo, lead author of the study. (SMOKING. Gah!!)

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It's terrifying, right?

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