Last Updated on June 30, 2020

5 Digestive Issues That Could Be Causing Weight Gain

5 Digestive Issues That Could Be Causing Weight Gain

Digestion is responsible for breaking our food down into nutrients. Because what takes place inside our intestines has much to do with how our bodies absorb carbs, fats and fiber, it should come as no surprise that digestion is directly linked to our weight.

According to the American Nutrition Association, 70,000,000 people are currently suffering from some kind of digestive issue. Whether the issue is acid reflux, IBS, Crohn’s disease or something else entirely, one thing is for sure: that’s a lot of people dealing with discomfort on a regular basis.

Most digestive issues tend to cause weight loss because of poor nutrient absorption, but some conditions have the opposite effect. If the number on the scale keeps rising and you’re not sure why, one of these common digestive issues could be a factor.

Gastro Esophageal Reflux Disease (GERD)

GERD, also known as acid reflux disease, causes chronic heartburn due to stomach acid coming back up through the esophagus. Why does this happen? Typically, people with GERD have weakened valves, which would normally keep these acids in place. Certain foods—spicy or oily ones, for instance—can exacerbate the symptoms of acid reflux, while others can soothe them.

But how does GERD cause weight gain? It’s primarily psychological. Some experts believe that weight gain comes from food anxiety. Some GERD sufferers overeat to treat the heartburn symptoms, which, of course, leads to weight gain. Unfortunately, GERD seems to be linked to high body weight to begin with, causing many patients to be trapped in a vicious cycle that makes it tough to shed those extra pounds.

Crohn’s Disease

Crohn’s Disease treats each person differently. For some, it can cause weight gain, while others might find that they have less appetite. But regardless of how it manifests, the disease’s treatment options often cause people to gain weight. This chronic condition often relies on steroids like prednisone, which reduce the body’s immune response to Crohn’s and, in turn, reduce swelling and inflammation. But steroids also affect your metabolism and how your body deposits fat, impacting your appetite and sometimes causing extra fat in the abdominal area.

If you’re experiencing weight gain from your Crohn’s Disease treatment, keep in mind that this usually only involves taking steroids on a temporary basis. Once your condition becomes more manageable, you can shift focus to losing weight.

Bacterial overgrowth

Small Intestinal Bacterial Overgrowth (SIBO) is a common gastrointestinal disease, yet it tends to command a lot less attention than its fellow acronymic disorder, GERD. SIBO is characterized by a combination of bacterial and fungal overgrowth that causes a range of intestinal symptoms.

Your body contains both good bacteria and bad bacteria. The good bacteria works to reduce inflammation and keep your digestive and immune systems running smoothly. But when the colony is thrown off balance, bacteria starts to produce methane gas. This slows the function of the small intestine and, in turn, allows your body to absorb more calories from the food you consume. SIBO also affects leptin and insulin resistance—meaning, it may have an effect on your body’s ability to regulate appetite and your metabolism.


If you’re all backed up, you might feel as though you’re weighed. But that bloating and discomfort could also signal actual weight gain.

While your body isn’t absorbing more calories, the extra fecal matter might tip the scale in the wrong direction. Make sure you’re eating a diet that consists of whole foods and plenty of fiber, followed by lots of water. It’s also important to work out, even if going to the gym constipated sounds like the absolute worst way to spend an hour or two. But remember, skipping out on activity in favor of the couch isn’t doing your digestive system (or the rest of your body) any favors.

If you’ve tried exercising, eating well and staying hydrated, yet something still feels “off,” ask your doctor if underlying issues are causing this irregularity. Constipation could be a symptom of an underactive thyroid, another condition that can cause weight gain.

Irritable Bowel Syndrome (IBS)

IBS is a fairly common digestive condition. The syndrome is linked to concerns like food sensitivities, leaky gut, constipation and intestinal microflora imbalance.

IBS can also cause bloat and inflammation, which may lead to that dreaded water weight. IBS is a chronic condition marked by its unpredictability. One day you’re constipated, the next you’re dealing with diarrhea. People often eat certain foods to soothe their systems and skip exercising when they’re in pain. The best way to deal with these issues is skipping out on foods that agitate IBS: beans, cabbage and carbonated water are three to keep out of your diet.

In the end, any digestive problem is a sign that something inside your body is off. If you’re experiencing persistent heartburn, constipation or diarrhea, talk with your doctor. Weight gain is just one problem linked to digestive issues, and failure to address these problems could spell even more issues down the road.

Cory is a veteran health industry writer and content creator. His work has been featured in major publications such as MyFitnessPal, Healthy Living, and Low Carb Fanatics. His health industry writing career spans over nearly two decades.

In his free time, Cory enjoys snowboarding, fictional writing, and online chess.