Here’s Why The Keto Diet Makes You Thirsty All The Time

Turns out “dry mouth” and cutting carbs go hand-in-hand.

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So—debates about how healthy it is be damned, you’ve decided to do the ketogenic diet. And a week in, you discover one of keto’s dirty secrets: it can make you thirsty as hell.

It’s something many encounter once they go keto and it can even turn some away from the program. After all, is normal to feel so damn parched all the time? Is the weight dropping off through pure dehydration?

Men’s Health explains that there’s a certain logic in the way keto triggers cottonmouth. People who choose that program to lose weight are increasing their “fat intake to about 80 percent of your daily calories and slashing carbs to below 50 net grams per day.” That, according to the magazine, “can take a toll on the body’s hydration.”

The secret is hiding in the diet’s name. It induces ketosis—switches on the body’s fat-burning torch. Carbs are big no-nos in the ketogenic diet and a lack of carbs starts burning up the body’s supply of glycogen, which Men’s Health says contains up to “3 grams of water.”

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To keto or not to keto?

Along with burning fat, keto also tweaks insulin levels. High insulin from carb consumption prompts the kidneys to retain water. Without more sugar, insulin drops and the kidneys drain as well.

The solution is pretty obvious: drink more water. Specifically water. Dietitian Ginger Hultin tells Men’s Health: “If your goal is to be in ketosis, many sports drinks or electrolyte replacements won’t be appropriate because the sugar content will be too high.” So choose to keep refilling with H2O. Add a bit of salt to maintain and enhance electrolytes.

In addition to water, dietitians recommend keeping a supply of keto-friendly leafy greens, avocados, or berries on hand.

Or you could just check out some informed opinions on keto and maybe even reconsider it altogether.