For those suffering from IBS [1] (irritable bowel syndrome), the bloating, stomach pain, constipation, and diarrhea are just some of the uncomfortable and sometimes debilitating symptoms. But can IBS also cause weight gain? Here's what registered dietitian and gut health expert Jessie Wong [2], MAcc, RDN, LD, who specializes in IBS, and NYC internist and gastroenterologist Niket Sonpal [3], MD, had to say.

How Can IBS Contribute to Weight Gain?

IBS can contribute to weight gain in a multitude of ways, Dr. Sonpal explained. He said that IBS is often linked to depression or anxiety, which can lead to overeating. Emotional eating usually occurs when someone feels stressed or upset, and food provides comfort. He added that lifestyle habits such as poor diet, dehydration, and lack of exercise which worsen constipation in IBS sufferers, can also lead to weight gain, a slower metabolism, and excess body fat.

Most people with IBS tend to lose their appetite due to the discomfort, Wong said, which actually leads to weight loss. But in other cases, Wong explained, "eating provides a different sensation that can mask the pain or discomfort from IBS, leading people to eat continuously, hence causing weight gain." In order to reduce IBS flare-ups, Dr. Sonpal also said someone may skip eating vegetables, fruits, and beans, and eat comforting, easier-to-digest processed carbs, which are more calorie-dense, another cause of weight gain.

Another reason IBS can contribute to weight gain is because of bloating [4]. "There are two major types of bloat that can happen in IBS; above the belly button or below the belly button," Wong said. Some people experience both types of bloat.

Above the belly button bloat, also known as upper gastrointestinal (upper GI) bloat, is bloat that usually happens soon after a meal, and the bloat may go away in two to three hours after eating. Wong explained that with this kind of bloat, people sometimes feel a burning sensation in their gut, and a lot of discomfort and cramps in their stomach area. "Some people resort to eating cold foods to find temporary relief to their symptoms," Wong said, and overeating on foods like ice cream, iced coffee drinks, and smoothies could contribute to weight gain.

Still another reason was found in recent studies which indicate that certain hormones in the digestive tract regulate weight [5]. These seem to be at abnormal levels in people with IBS, either higher or lower than expected, and weight may be affected by these changes in gut hormone levels.

What Can Someone Do If Their IBS Is Causing Weight Gain?

Since the bloat, pain, and discomfort are the main reasons why some people are disconnected from their body's natural hunger cues leading to overeating, Wong said that learning to manage their IBS is the first step to stopping the weight gain.

Oftentimes, people are told to just live with their IBS, but in reality, there are effective treatments that can help you identify what is causing your IBS, and you can learn to manage it, she said. "It usually requires dietary and lifestyle changes, and sometimes working through the FODMAP [6] protocol to identify personal food triggers," Wong said.

Try this:

• Dietary changes: Wong said to expand the variety of plant-based foods [7] you eat to increase fiber consumption. Aim for 30 grams of fiber a day [8] and 30 different types of plant-based foods a week. Focus on eating foods such as whole grains, fruits, and veggies, as opposed to powders, sugar substitutes, or supplements. Limit the high-fat foods, whole milk products, alcohol, caffeine, refined carbs, fast food, and junk food, as Dr. Sonpal said these foods can contribute to IBS symptoms and weight gain. Eating many smaller meals may also improve symptoms as opposed to eating a few large meals, Wong said. And whenever you can, Dr. Sonpal said to cook your meals at home.
• Hydration: Adequate hydration is also important, said Dr. Sonpal. Aim to drink at least half of your body's weight in pounds in fluid ounces; so if a person weighs 160 pounds, aim to drink 80 ounces daily as a baseline. If you exercise, your fluid intake need will be higher.
• Lifestyle changes: This refers to stress management, improving sleep quality and quantity, and getting some gentle to moderate exercise. "Intense exercise is not recommended as it draws blood away from the intestines, which can increase inflammation in the gut and make symptoms worse," Wong said.
• FODMAP protocol: FODMAPs [9] refers to fermentable carbohydrates (the name is an acronym for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols.) These carbohydrates are short-chain fibers and sugars that our body doesn't digest, and our gut microbes ferment it. They are very good in providing fuel for our gut microbes, but for people with IBS, it can cause distention and bloating, Wong explained.

  The FODMAP protocol is a temporary elimination and reintroduction protocol to find out which types of fiber and sugar you don't tolerate. The low-FODMAP diet is not a long-term diet, and you should work with a trained dietitian to get through it. Newer research suggests people staying on the low FODMAP diet for longer than eight weeks will start seeing a decrease in their good gut microbes, leading to worsened symptoms.

This isn't something you have to deal with on your own! "If you suffer from IBS and are struggling with weight loss or weight gain, it's always recommended to work with a dietitian who specializes in gut health to help you with weight management," Wong said.