Keto Constipation: It's Real & It's Gnarly

The most common phrase you’ll hear when you ask people about constipation is: “I hate to be graphic, but…” This is how dietician Ashley Lytwyn prefaced her explanation of why, physiologically, you might feel constipated while on the popular ketogenic diet. This diet involves ditching most carbs in order for your body to go into “ketosis,” a time when your body burns its reserves of stored fat to fuel itself.

“When you cut those carbs from your food intake, you don’t get the properties that help create bulk within the stool, and, it’s graphic, but those properties pull that stool down your digestive track,” Lytwyn, M.S., RDN, LDN, and founder of Nutrition Unveiled, says. “Carbs are fibrous and they create weight in your stool which helps gravity pull that waste through your body to be eliminated.”

But that’s just the beginning of the story.

Not every keto dieter will feel constipated, but it’s not an uncommon side effect. Dr. Richard Firshein, D.O., a leading expert in integrative and precision-based medicine and founder of Firshein Center, says that when you’re deprived of an adequate amount of fiber from carbs, your body isn’t able to regulate itself and what comes out of it. For the record, The American Heart Association, recommends adults get 25 grams of fiber per day on a 2,000-calorie diet.

But that’s not the only reason you might feel constipated on keto.”The most common reason for constipation on low carb diets is dehydration,” Firshein says. This is because carbs are converted into glycogen, which also happens to store water. But your body burns glycogen as it works its way into ketosis, according to Firshein. So the more glycogen you lose, the more dehydrated you become. Studies have shown that dehydration can lead to constipation. Isn’t it wild how everything is connected? And there’s more.

“It’s also the general probiotics,” Firshein says. “You’re not getting adequate amounts of the compounds and fiber that support the growth of bacteria. You’re not getting the bulk of bacteria, and not growing the same types of bacteria, so your gut biome is not developing properly.”

Aside from being uncomfortable, Lytwyn says that constipation can be a warning signal from your body that something might need to change. Constipation can cause long-term problems for you bowel, especially if you try to get things moving with laxatives, which your body can ultimately become dependent on, Lytwyn says. This could lead to issues with your intestines.

“Constipation is generally cause for concern,” Lytwyn says. “Your body is constantly sending you messages. But as fast paced Americans, I think we often ignore these messages.”

Now you know why it’s happening, but you might be wondering if it’s possible to relieve the constipation. Lytwyn generally doesn’t recommend keto, but she says if you ramp up your veggie intake while on the diet, it can increase motility for the digestive tract.

Firshein adds that, in general, a way to deal is to include more fiber-rich vegetables as a base or as a foundation for each meal. Specifically, leafy greens, Brussels sprouts, broccoli, artichokes, or avocado.

He also recommends supplements such as chia, flax seed, and aloe. You can also take probiotics to regulate the gut biome. Lastly, as always, it’s important to ensure you’re getting enough water in your diet to avoid the dreaded dehydration constipation.