There's no single answer to the question, "Why do protein bars give me gas?" In fact, there are many reasons you could be having trouble. It could be the protein or an added ingredient that's not sitting right with you. The protein bar could also have added fiber that your body needs to adjust to.
If you're eating protein bars and stomach pain follows, it may be time to switch to the other protein bars that don't cause gas or do some troubleshooting to figure out what the underlying problem is.
High-Protein Diet and Flatulence
Gas and flatulence are common complaints when first starting out on a high-protein diet. If you're eating protein bars as part of a high-protein diet, it's possible that you're just getting too much protein in a short period of time and your digestive system is having trouble with it.
According to the International Milk Genomics Consortium, proteins take longer to break down in the stomach than carbohydrates, and milk-based proteins like whey, which are commonly the main ingredient in protein bars, is one of the slowest digesting proteins of all. This slow movement of protein is what's responsible for a lot of protein's connection to weight loss and weight management; it helps keep you full longer so that you're less likely to overeat.
However, in some cases, it can cause gas, bloating and flatulence, especially if you're consuming too much protein in a short period of time. The International Milk Genomics Consortium also notes that casein proteins form curds in the stomach, making it harder for digestive enzymes to digest them.
Protein Bars and Stomach Pain
But if the protein bars you're eating give you gas and stomach pain even if your diet isn't that high in protein otherwise, there might be another issue with the type of protein you're eating. Whey protein, which comes from milk, contains lactose, a sugar that many people can't properly digest. If you're one of those people, it's likely that you'll get gas after consuming whey protein or other milk-based proteins, like whey.
It's also possible that the protein bars contain an ingredient that you're sensitive to or a sugar alcohol, like malitol or sorbitol, that's known for causing gas and bloating. Sugar alcohols are a common ingredient, especially in protein bars that are marketed as low-carb or keto-friendly. Some manufacturers also add fiber powders, like psyllium, to their protein bars.
While fiber can keep you regular and help eliminate gas in the long run, increasing your intake too quickly or eating too much fiber at one time can actually have the opposite effect, according to the Mayo Clinic. If fiber is the issue, increasing your water intake can help alleviate some uncomfortable symptoms until your body adjusts.
Read more: How to Stop Having Gas From Protein Shakes
Preventing Gas Attacks
Whether it's the protein itself or something else in the protein bars that you're eating that's giving you gas, there are some things you can do to prevent gas and make yourself a little more comfortable.
The first thing to do is avoid the culprit. While there's no one-size-fits-all list for protein bars that don't cause gas, the best thing to do is do a little detective work for yourself. Try different types of bars out and write down their ingredients — both the major protein source and any added ingredients. Take note of which bars give you gas and which ones don't and see if you can find any similarities between them.
Is the main protein the same? Do they all share a common added ingredient, like malitol? Are they rich in fiber? If you can find patterns, you can avoid the bars that are problematic for you and stick to the protein bars that don't cause gas. The International Foundation for Gastrointestinal Disorders also recommends:
- Taking digestive enzymes
- Eliminating other foods in your diet that may be problematic, like beans and bran
- Avoiding carbonated beverages