It's time for some real talk about a potentially less pleasant topic: bloating. Many people experience it, especially those who consume a lot of protein. Protein, the very thing that makes us healthy and strong, may also be contributing to uncomfortable, potentially embarrassing gas and bloating. The good news is that by being aware of the problem and its potential causes, you can make small changes to address it.
What is Protein Bloating?
Protein bloating is the buildup of air (gas) in your body, more specifically your intestines, when eating protein. As you might imagine, this causes discomfort and potentially embarrassing and annoying gas, and it could make you feel like someone is inflating a balloon inside your belly.
Protein bloat can be attributed to a number of factors. First, let's look at the science behind this. Protein's thermic effect, or the amount of energy needed to digest it, is very high, higher than any other macronutrients. For the most part, this is a great thing because this is why protein fills you up and keeps you satisfied for way longer than carbs. But here's the downside: this means lots of this protein can sit in our gut, undigested, which leads to indigestion and, you guessed it, gas and bloating.
This isn't the end of the story; you don't need to cut all that amazing protein out of your diet. Work to find a solution for your body. Be sure you're balancing with other macronutrients like complex carbohydrates and fats. Healthy fats are integral to digestive health because they really move things along through your digestive system. What counts as a healthy fat? Tons of the things you probably crave anyway: cheese, nuts, salmon, avocado, and olive oil, just to name a few!
Complex carbohydrates are rich in fiber; think whole wheat bread and pasta, whole grains, sweet potatoes, and beans. Fiber is integral to a healthy digestive system.
Read also: High-Fiber Diet for Better Health
Understanding Protein Farts
If you're looking to get stronger, you may have started upping your protein consumption, as the muscle-building macronutrient is an MVP when it comes to hitting fitness goals. A potential downside you may be experiencing, though, is something called protein farts.
Eating foods with amino acids, the building blocks that make up protein, can help the body repair muscle proteins that have been broken down during exercise and create new ones through muscle protein synthesis. So it stands to reason that those who have a goal of building muscle crank up their protein intake both before and after a workout.
Unfortunately, amping up your protein consumption can also do a number on your gas game, even when you're within the recommended range of healthy macronutrient consumption. Here's what you need to know about why you might be experiencing so-called protein farts after increasing your protein intake, plus how to prevent them.
"Protein farts" is a term that refers to increased flatulence or smellier-than-normal gas that some people experience while consuming a diet higher in protein, explains Danielle Crumble Smith, RD, a registered dietitian and spokesperson for Top Nutrition Coaching.
This term is used frequently by people who say they notice this unpleasant side effect after eating more protein, but it's not well-studied. “Despite chatter around protein farts when people increase protein intake, scientific research to support this phenomenon is weak,” says board-certified sports dietitian Kelly Jones, RD. That being said, excessive protein intake in one sitting (especially of certain types of protein, such as protein powder) may affect how the bacteria in the lower digestive tract interact with amino acids, creating more foul-smelling byproducts, Jones adds.
Read also: Delicious High-Fiber Smoothie Recipes
What Causes Protein Farts?
A variety of things could be causing these so-called protein farts, but the cause isn't usually the same for everyone. That's why Desiree Nielsen, RD, a registered dietitian and the author of Plant Magic, recommends putting on your detective cap to figure out why protein makes you fart. “We need to do some sleuthing to determine if their protein choices may be contributing to digestive ills or if it is something about their dietary pattern as a whole,” she says.
Here are some potential causes of protein farts to consider:
1. Protein Intake “Crowding Out” Fiber-Rich Foods
Eating a high-protein diet often happens at the expense of higher-fiber choices, which can hamper digestion or even cause constipation and an increase in gas, Nielsen says. More time between bowel movements means more time for waste products to interact with bacteria and ferment in the digestive tract, potentially lending to increased flatulence and smelly protein farts.
2. Gut Bacteria Fermentation Byproducts
If the protein you're eating reaches the large intestine undigested, the gut bacteria must break it down through fermentation. This task produces various gasses including hydrogen, methane, and in some cases, sulfur compounds. “This process can increase the volume and odor of flatulence, especially if there are already gut imbalances,” Smith says.
3. Dehydration
If you've recently upped your protein intake pretty dramatically, while also upping your time spent exercising (as one might when trying to put on muscle), hydration may be part of the problem, Jones says. “Those with an ‘all-or-nothing’ mentality in the gym may also be more likely to go on strict low-carb diets, reducing intake of healthy plant foods that support normal digestion, leading to an increase in digestive distress,” Jones says. Consuming more protein and fewer carbs may increase fluid needs, she continues, “and not increasing fluid and electrolyte intake appropriately can also lead to constipation.”
Read also: Explore the pros and cons of a high metabolism diet
4. Enzyme Overwhelm
The body has specific enzymes to break down proteins. A sudden increase in protein can temporarily overwhelm these enzymes, leading to incomplete digestion, according to Smith. And again, when proteins aren't fully digested in the small intestine, they reach the large intestine and end up producing gasses.
5. Increased Saturated Fat Consumption
“If your new high-protein intake also comes with a higher fat intake, both of these nutrients can lead to a slowdown in gut motility, which could contribute to gas output,” Nielsen says. This is especially true if that fat is saturated fat, which can also be challenging to digest and absorb in large amounts, Jones says. Sure, that 16-ounce ribeye at a steakhouse looks like a win at 90 grams of protein, but the 80 grams of fat stresses the digestive tract, often resulting in more proteins reaching the lower digestive tract and causing undesirable gas.
6. Sulfur-Containing Amino Acids
Foods high in protein, especially animal proteins like meat, eggs, and dairy products, naturally include sulfur-containing amino acids, including cysteine, methionine, and taurine. “When these amino acids are broken down in the gut, they can produce hydrogen sulfide, a gas that gives farts their characteristic unpleasant odor,” Smith says.
7. Ingredient Intolerance
Have you been leaning on protein powder to up your protein intake? Whey and casein protein powders, “which are popular among fitness enthusiasts,” according to Smith, are derived from dairy and may contain lactose. It's estimated that nearly 70 percent of the world’s population has difficulty digesting lactose. For these populations, consuming lactose can lead to increased gas production, bloating, and flatulence, Smith says.
Beyond that, many protein supplements contain artificial sweeteners such as sugar alcohols (erythritol and sorbitol are two common examples), which tend to be difficult to digest and can ferment in the gut, leading to gas and bloating.
“I encourage my clients to try to stick to proteins with minimal ingredients and look for ingredients that they recognize and/or can pronounce,” Smith adds.
8. Adjusting to Plant Protein
If you’ve been eating more plant-based proteins like chickpeas, beans, and lentils, these can cause gastrointestinal (GI) symptoms in certain people, says Anthea Levi, RD, a registered dietitian and founder of ALIVE+WELL Nutrition. “If you’re not accustomed to eating a plant-forward diet, markedly increasing your dietary fiber intake from plant-based proteins may cause gas and bloating at first,” she says. Legumes also contain specific types of carbohydrates called galactooligosaccharides (or GOS for short) that can be difficult to digest. “GOS are readily fermented by bacteria in the gut, which means they're also more likely to promote gas and bloating in sensitive individuals,” Levi explains.
The good news? With a little time, your body will adjust to plant proteins: “Despite the associations between beans and flatulence, those who consume beans regularly have gut bacteria that adapt to the regular intake of more fiber and prebiotics, which can actually offer gut health benefits,” Jones says. “After several weeks of regular legume consumption and bacteria adaptation, flatulence should subside.”
Are Protein Farts Normal?
First things first: Gas as a general concept is totally normal. It’s actually an indicator of a healthy, functioning digestive tract, Nielsen confirms. It’s normal to pass gas every day; in fact, the average person farts 14 times each day. And if you’ve been upping your protein lately, it’s unsurprising to be experiencing these so-called protein farts too.
Any substantial diet changes, including a rapid increase in protein intake, can slow digestion slightly as the body acclimates to its new normal, Nielsen says. So if you notice an increase in gas, or gas aroma, for a couple of weeks and then things return to their usual levels, that means your body is responding just as planned.
“Long-term protein farts aren’t a universal experience though, so it’s worth being curious,” Nielsen says. “Keep a food and symptom journal for a week or two to try to pinpoint what the culprits might be.”
Maybe your pre-workout snacks are a bit too protein-strong, for example, and having that food in your gut during a tough running or cycling workout is triggering indigestion. Or maybe you’re not drinking enough water throughout the day, which can cause sluggish digestion. Perhaps those extra eggs and cheese sticks are crowding out your more fibrous noshes, so you’re experiencing constipation or gas.
Symptoms like protein farts are neither “good” or “bad,” Nielsen says. “They just are! If that’s all you are noticing from your dietary shift but it doesn’t really bother you, and isn’t combined with any other troubling symptoms, you could just give your body some time and see if it adjusts,” she says.
Still, while protein farts often aren't a cause for concern, they could be a call to action for you to fine-tune your diet. Balance, moderation, and experimentation (say, swapping protein powder for a whole-food protein source like chicken) are often helpful to keep top of mind if you notice that the protein farts are persistent. That said, if protein farts do bother you, or if you or your doctor are concerned that they might be a sign that something in your digestive system is a little out of balance, there are some things you can do to prevent them.
How to Stop Protein Farts
As we mentioned, gas is a totally normal part of being alive. But if your protein farts are particularly frequent or smelly, try any or all of the steps below to get things under control.
1. Go Gradually
As you embark on adding more protein to your menu, do so one meal or snack at a time. For example, you might add an extra protein source to breakfast as you keep the rest of your day’s menu consistent for a week. Then pack your breakfast and post-workout snack with protein the next week. “This gives your digestive system time to adjust to the increased protein load,” Smith says.
2. Ease Into Plant Proteins Too
Same goes for adding more plant-based food sources to your diet. If you don’t typically eat a lot of high-fiber plant proteins, plan to increase your intake slowly to help your body build up a tolerance, Levi says.
3. Take a Break From Packaged Foods
Many busy individuals on a high-protein diet turn to packaged items like bars and shakes, not realizing that they’re sensitive to the large amounts of prebiotic fibers, sugar alcohols, or dairy in the mix. Swapping in plant-based protein foods such as nuts, seeds, quinoa, or even beans may tackle two problems at once: increasing fiber and eliminating intolerance.
4. Balance Your Diet
“It’s also really important to focus on balance, even if your diet is protein-heavy,” Smith says. “Include fiber-rich foods like complex carbohydrates, vegetables, and fruits as well as healthy fat and adequate fluid to help support bowel regularity, which can help reduce the effects of protein farts if they are a result of constipation.”
5. Stay Hydrated
Aim to drink about half of your body weight (in pounds) in ounces of water each day. So if you weigh 160 pounds, shoot for 80 ounces daily. Proper hydration supports digestion and the integration of nutrients, including protein, Smith explains.
6. Choose Lean Protein Sources
According to Smith, lean meats (like chicken, turkey, and fish) and plant-based proteins (like lentils, chickpeas, and quinoa) are generally easier to digest than meats high in saturated fats.
7. Try Different Protein Types
If you use protein supplements, play around with them. Plant-based or dairy-free protein powders might be a better fit for your gut than whey or casein protein, which have been linked to slower gastric emptying. (If you take this route, a smart place to start is getting your doctor’s OK to try a new supplement and then selecting an option listed in the National Sanitation Foundation’s Certified for Sport® directory.)
8. Eat Smaller, More Frequent Meals
Consuming small amounts of protein throughout the day instead of large amounts in one sitting can ease digestion and give your body enough time to utilize the protein for muscle-building rather than energy storage.
9. Tune In to Avoid Gas-Triggering Foods
Each gut responds to foods differently, and some people may find that certain protein-rich foods simply cause them to produce more gas. Rather than sticking to the same routine each day or week, aim to be mindful of how your body reacts to different foods and, if you don’t adjust after eating them for some time, consider cutting back on any of your personal protein-fart generators.
10. Move Your Body
“Regular physical activity can improve your digestion and reduce bloating,” Smith says. Health experts recommend shooting for at least 150 minutes of moderate cardiovascular activity per week, plus two days of full body strength training.
11. Prioritize Probiotics
Consuming probiotic-rich foods like yogurt, kefir, and fermented vegetables (or taking a probiotic supplement if your healthcare provider advises it) can support gut health and potentially reduce gas of all kinds, Smith says, including protein farts.
12. Try Ginger
If you think that your gas might be caused by sluggish digestion, try adding about a 1-inch piece of peeled fresh ginger to a smoothie or grating it into oatmeal. “Ginger is pro-kinetic, meaning that it helps facilitate the movement of the gut,” Nielsen says. “It's a great food-based digestive aid.”
13. Consult a Dietitian
Persistent and excessive amounts of gas might be a sign of a gut imbalance, so it’s wise to work with a registered dietitian to identify your potential triggers if your body doesn’t seem to adjust to increased protein intake. “If the gas is excessive or accompanied by discomfort, bloating, or other symptoms,” Smith says, definitely speak to a dietitian for personalized guidance.
Additional Considerations
The Role of Fiber
People who eat high-fiber diets are more likely to experience bloating if their high-fiber diet is protein-rich as compared to carbohydrate-rich, according to a study led by researchers at the Johns Hopkins Bloomberg School of Public Health.
The researchers determined that when the 164 trial participants ate versions of a heart-healthy, high-fiber diet that was relatively rich in plant protein, they were about 40 percent more likely to report bloating symptoms than when eating a carbohydrate-rich version of the same high fiber diet.
The study suggests that people who want to eat a high fiber diet would be less likely to experience bloating if the diet were relatively carb-rich versus protein-rich.
High-fiber diets are believed to cause bloating by boosting certain populations of healthful fiber-digesting gut bacteria species, which produce gas as a byproduct. The findings thus also hint at a role for “macronutrients” such as carbs and proteins in modifying the gut bacteria population-the microbiome.
Potential Downsides of Carb-Rich Diets
There is the possibility, however, that making high fiber diets more tolerable in this way would also make them less healthy. The plant- protein- and fat-rich diets in the study, which led to higher bloating prevalence, also appeared, in the original OmniHeart trial analysis, to lower blood pressure and improve blood lipid measures more than the carb-rich diet.
Researchers have been uncovering evidence that many of the effects of a healthier diet come from shifts in the gut microbiome that result in greater microbial production of health-promoting molecules called metabolites.
Protein Supplements and Additives
If you notice an increase in farting, chances are protein itself is not the culprit. Instead, protein powder additives and certain food components might be why you’re experiencing increased flatulence.
While protein itself does not increase flatulence, protein supplements may contain other substances that make you gassy. Supplements that are based on whey protein or casein may contain high amounts of lactose. A high intake of lactose can increase flatulence, even in people who usually consume dairy products without any problems.