If you’re reading this, chances are protein ranks high on your list of priorities. It builds muscle, curbs cravings, and aids recovery, making proteinmaxxing less of a fleeting trend and more of an obvious lifestyle choice. But if you’re one of the roughly three million Americans living with inflammatory bowel disease (IBD)—like Crohn’s or ulcerative colitis—that protein obsession hits a little differently. On one hand, chronic inflammation and malabsorption might increase protein needs. Flares can also strip weight fast—potentially taking muscle along with it—making it seem smart to bank as much of the macro as you can. But certain protein-rich foods, or simply eating too much of it, can irritate an already volatile gut.
So are all those shakes and steaks helping your cause or unwittingly making things worse?
When protein backfires
More protein isn’t always better, especially when your gut lining is inflamed. “Most of the protein you eat is meant to be broken down and absorbed in the small intestine,” says Karan Rajan, MD, a gastrointestinal surgeon and the founder of LOAM. “But when your diet is excessive in protein and fiber poor, more of that leftover protein can spill into the colon,” leading to inflammation and symptoms like bloating, cramps, diarrhea, or nausea.
Adrian Hernandez, MS, RDN, a certified gastrointestinal dietitian nutritionist and owner of AEH Nutrition in Washington, DC, adds that urgency and flatulence can also result from improperly digested protein. He says that excess protein can overwhelm your body’s ability to produce pepsin and protease enzymes, which break down protein into amino acids. “As a result, undigested protein ferments in the colon, producing byproducts like ammonia and hydrogen sulfide, which cause sulfur-smelling gas,” he says. “High hydrogen sulfide levels can also harm cells lining the colon that protect against mucosal damage and inflammation.”
So what’s the safe zone for intake? Per Hernandez, those with IBD should generally aim for no more than 1.2 to 1.5 grams of protein per kilogram of body weight (though the exact amount will vary by physical activity levels and other personal factors).
The best and worst protein sources for IBD
Gram count isn’t the only point you need to consider. The type of protein you eat also holds sway over your symptoms and overall health. Red meat (especially fatty cuts) is one of the biggest red flags for those with Crohn’s or ulcerative colitis, so limit or avoid it outright. “High intake is linked to a greater risk of IBD and colon cancer, likely due to saturated fat content,” says Hernandez. Moreover, he warns that colon cancer risk rises in those with IBD due to chronic inflammation.
Cold cuts and processed meats also linger in the danger zone, says Hernandez, as their preservatives and additives are pro-inflammatory and possibly carcinogenic. Unfortunately, convenient protein sources like bars, shakes, and powders might not be doing your colon any favors, either. “These can contain added sugars, artificial sweeteners, emulsifiers, preservatives, and high amounts of fat (bars especially),” which can exacerbate symptoms, Hernandez says. If you’re not willing to ditch them completely, choose options with minimal ingredients and reach for them sparingly.
But it’s not all doom and gloom. There are plenty of protein sources that get the green light for guys with IBD. According to Dr. Rajan, lean meats like chicken and turkey, as well as eggs and fish (especially those rich in omega-3s, like salmon and sardines), tend to be safe bets. “Don’t forget that non-animal proteins count too,” adds Sophie Dolan, MS, RD, a dietitian specializing in IBD management in Birmingham, Alabama. “Try adding some tofu, beans, legumes, lentils, and nut butter as tolerated to meet your protein goals.” Some of these plant-based foods are high in fiber, which may not be well-tolerated especially during a flare, says Hernandez. Aim to introduce them gradually and hold back when you’re symptomatic.