Restrictive Dieting May Shorten Your Life, So That's Bad News for Keto Dieters

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So you know how everyone (even famous trainers) and their mom swears the keto diet is the best thing that's ever happened to their body? Turns out, restrictive diets like keto could actually have seriously harmful consequences—like shortening your life span, according to a comprehensive new study published in the journal Lancet.

People who derived less than 40 percent or more than 70 percent of their daily calories from carbohydrates were more likely to die than people who ate a percentage in between those numbers, researchers found. Translation: Your diet need's balance; no tipping the scales one way or another. The authors reached this conclusion after tracking the diets of almost half a million people (more than 15,400 adults in the U.S. and an additional 432,000 people in 20+ other countries around the world). Then they took that info and compared it against how long these people lived.

Considering that the keto diet calls for sourcing just around 5 to 10 percent of your daily calories with carbohydrates—with 70 to 75 percent of your calories coming from fat and 20 percent from protein—it certainly falls outside of the ideal limits determined by the study. And it's not the only restrictive diet that comes under fire with these findings: High-fat, low-carb diets like paleo, Atkins, Dukan, and Whole30 also force your body to tap into its fat stores for energy versus burning carbohydrates (hence the super short-term weight-loss results) and are just as limiting.

This isn't the only time long-term, low-carb diets have been linked to a higher mortality rate. Additional research, which tracked the self-reported eating patterns of nearly 25,000 people, was presented at the European Society of Cardiology Congress this summer and concluded the same early death findings. Studies have shown that besides, you know, early death, there are a lot of drawbacks to restrictive diets (not the least of which is that they're incredibly tough to stick to): They can trigger overeating, cause social withdrawal, deprive your body of important nutrients, and lead to disordered eating habits. And, for what it's worth, the keto diet was ranked all the way down at number 38 in the U.S. News & World Report's 2019 list of the best and the worst diets. (Even Jillian Michaels hates keto.)

But there is good news: What the study authors did find was that a diet "rich in plant-based whole foods such as vegetables, whole grains, legumes, and nuts is associated with healthy aging," said lead researcher Sara Seidelmann, M.D., Ph.D., a cardiologist and nutrition researcher at Brigham and Women's Hospital in Boston.

Sounds a lot like the Mediterranean diet, right? Makes sense, because the Mediterranean diet was at the top of the U.S. News & World Report's rankings this year. (Related: Mediterranean Diet Cookbooks That Will Inspire Your Healthy Recipes for Weeks to Come)

Essentially, though, this new report is saying that eating a well-balanced, healthy diet will send you cruising into old age. But, real talk for a second: Do we really still need massive studies to tell us this?! Sure, everyone wants a magic solution for weight loss, and while keto definitely does yield short-term results, there's no long-term replacement for balance and moderation in your diet.