Bloating 101: What Is Bloating & What Causes It?

For some people, bloating is occasional and mild. For others, it's a more daily affair. It can make you feel gassy, "stuffed," or heavy, especially after meals. As a medical doctor who specializes in gut health, I can tell you bloating is a common complaint I hear. "I want to take off my pants, put on my sweatpants, and watch Netflix on my couch alone," one person recently told me.

In fact, around 15 to 30% of Americans regularly experience bloating1. It can be visible or simply a feeling. For most, the reason for bloating is too much intestinal gas, and it can be caused by a number of things.

Many times, helping people beat bloating requires a bit of digging to find what's creating the issue in the first place. It's also important to acknowledge that bloat can be a symptom of certain conditions like irritable bowel syndrome1 (IBS), inflammatory bowel disease, and other functional gastrointestinal disorders—for which you would want to seek the advice of a health care practitioner.

That said, after helping hundreds of individuals, I've pinpointed a few lesser-known culprits of bloat you'll probably want to note:

Many bloating problems come down to food. Overeating can certainly create bloating, along with consuming fried foods, too many carbs, and processed foods.

Overdoing fiber can also create bloating. While dietary fiber is great for your gut, increasing the amount too quickly can be a problem. If that's the case, slow down and add fiber gradually. 

Certain foods including dairy and legumes can also create bloating in some individuals. Many people have intolerances to these foods, or the inability to fully break down that food with digestive enzymes, which further leads to irritation. For these people, I use an elimination diet to remove potentially problematic foods. We then carefully reintroduce those foods, one at a time, to pinpoint what is contributing to the bloating. 

Underlying many of these gut disorders is an imbalance of one's gut microbiota, between favorable and unfavorable microorganisms in the digestive tract. Your gut contains about 500 to 1,000 species of bacteria. And the tiniest shifts in the relative predominance of these bacteria can affect how your gut works2.

An overpopulation of bacteria in the small intestine can increase fermentation of sugar in the carbohydrates you eat, and bloating can occur from this gas production1. As a result, people with this issue should limit carbohydrates, including starches, sweets, and sugars. To address this unique need, I use a carefully designed nutrient plan and implement an elimination diet, which cuts out all sugars, including sneaky sweet sources.

In a different case, one's small intestine can become imbalanced, overpopulated with too much yeast or fungi3. One type of fungus, a yeast called candida, can wipe out other friendly, symbiotic bacteria, and the imbalances in your gut bacteria may lead to gas and other digestive challenges. Interestingly, a diet rich in sugar and simple carbohydrates is also often the culprit here.

Some individuals experience bloating within minutes after eating a meal that contains protein. They may also find they belch a lot. "After I eat, it feels like I've got a brick sitting in my stomach for an hour," one person told me. 

Low stomach acid–not too much—can cause issues after eating. When you don't have enough stomach acid to adequately break down protein, food sits undigested in the stomach longer.

The most common sign of low stomach acid is a feeling of bloating or stomach expansion after eating a protein-rich meal. If you experience this on a regular basis, you might benefit from supplementation. I often recommend hydrochloric acid supplements as a targeted approach, but be sure to consult with your health care provider before giving this a try.

Sometimes pinning down what creates bloating can require some trial and error. Carefully tracking what you eat, when you eat it, and any accompanying "gut feelings" in a journal can help better pinpoint the problem. This is an important step in developing food-gut intuition—your ability to tell which foods personally disagree with you and which ones lead to a happy gut.

Once you identify what contributes to the bloating, the diet should be personalized to limit specific problem foods and create a plan that supports overall gut health. I also often recommend lifestyle modifications, including stress management and regular exercise.

There are a number of reasons you may be feeling bloated occasionally. Being mindful of when you feel bloated can help you get a better understanding of the root causes. If you experience chronic bloating, speak to your doctor about your best options.