Can IBS Cause Weight Gain and What Can You Do About It

Patients with gastrointestinal problems often experience unprecedented weight change as a side-effect of their disorder. Weight gain or loss can occur depending on a handful of factors.

For example, patients with IBS experiencing constipation and abdominal pain may keep themselves from eating in order to alleviate symptoms. On the other hand, patients with GERD may find themselves eating constantly in order to suppress acid flare-ups. 

So can IBS patients experience weight gain? Yes. This could be due to a host of factors involving hormonal activity, diet, and lack of exercise. The good news is that weight gain from IBS is easily manageable with lifestyle changes. 

How IBS Causes Weight Gain 

Weight change from IBS is likelier to result in weight loss. For irritable bowel syndrome patients, this could be caused by the inefficient nutrient absorption from food and urgent bowel movements that can come right after eating. The discomfort may be associated with food, which could prevent patients from eating.

Read more: Irritable Bowel Syndrome: Symptoms and Causes

While uncommon, IBS patients can also experience weight gain which involves a few factors. These include:

1. Hormonal Activity

One study suggests that weight gain from IBS is due to the hormones residing in the gut, specifically those that control appetite. Researchers found that hormones related to appetite are abnormal in IBS patients. Increased food intake and an insatiable appetite could be the result of fluctuating gut hormones. 

2. Obesity and IBS

Some scientists believe that existing weight problems may contribute to the development of IBS. However, further studies are required in order to properly establish a link between obesity and IBS. Meanwhile, another study pointed out that IBS symptoms are aggravated in obese patients because of the problems in satiation signals in IBS patients. 

3. Improper Diet

Patients with irritable bowel syndrome have more limited food options than healthy people. Dietary restrictions can lead to nutritional imbalance and overeating. Some patients could be consuming more rice, mashed potatoes, and starchy foods more than other food groups in order to alleviate certain symptoms.

Even certain fruits and vegetables are considered food triggers for IBS patients, which can make meal preparation more challenging. As a result, patients can stick to eating certain foods which could be calorie dense, resulting in weight gain. 

4. Complications With Physical Activity

HIIT (high-intensity interval training) is one of the best ways to lose weight. Unfortunately, it is also one of the easiest ways to trigger IBS symptoms. Exercises that involve running and jumping can also trigger gastrointestinal stress. Patients may find themselves reluctant to hop on a treadmill in fear of setting off symptoms. 

Weight Gain VS Bloating

woman touching her belly and holding a pink ballon

Bloating is a common symptom of IBS and could be interpreted as weight gain. While the actual cause of bloating is still unknown, excessive gas does not actually cause bloating.

Other causes could be impaired motility (intestinal muscle contractions that move food and other contents through the walls), bacterial growth in the small intestine, and sensitive abdominal walls to name a few.

It’s fairly easy to differentiate bloating from weight gain: bloating often lasts for 1-5 days and is centered on the stomach, while weight gain is apparent in all areas of the body and usually does not recede on its own. 

Bloating also has the following characteristics:

  • Commonly described as increased abdominal pressure
  • Often gets worse immediately after meals
  • Stomach can start flat out in the day and get bloated at night
  • Usually subsides overnight 

It is one of the more manageable symptoms of IBS. Below are some tips for dealing with bloating: 

  • Eat slower: For some people, bloating is only perceived and can’t be physically observed. To reduce the feeling of pressure around the abdomen, we recommend eating smaller meals to prevent discomfort. 
  • Take digestive supplements: Over-the-counter digestive enzyme supplements are available to help people absorb indigestible carbohydrates. For example, the intestine is not equipped with enzymes to digest a string of enzymes called FODMAPs, which could require people with sensitive intestines to get supplementary aid. 
  • Watch your diet: Foods high in sugar and salt can lead to water retention and result in distention, or the physical increase in abdomen size. Drinking a lot of water to dilute the sugar and salt content is useful in flushing out the excess. 

How to Lose Weight With IBS

ibs weight loss plan

Patients with irritable bowel syndrome don’t have to carry the extra weight forever. There are ways to slough off weight from IBS by doing the following: 

1. Seek Medical Advice

It’s difficult to manage weight gain without seeking help from a gastroenterologist. Weight changes related to gastrointestinal problems could be caused by problems not easily resolved by calorie counting. Medical professionals can run tests and identify what exactly is causing weight gain. 

If it’s hormonal imbalance, your doctor may prescribe supplements to keep your hormones stable. If it’s bacterial growth, your patient can recommend antibiotics to fight off infections. Knowing what’s causing your weight gain is the first step to losing it. 

2. Plan Healthy Meals

As an IBS patient, you should strive for a nutritional plan that does not only alleviate your symptoms but is also highly nutritional. It’s challenging to find foods that don’t trigger symptoms while simultaneously preventing weight gain. 

We suggest getting in touch with a licensed nutritionist who is informed with gastrointestinal problems. Together, you can plan healthy meal plans that are nutritious and well-balanced, while ensuring your symptoms are kept under control.

3. Find Alternative Exercise

Although HIIT and most cardiovascular exercises are out of the question, there are other activities that can be done which are safe for IBS patients. Instead of running, you can swim thrice a week to build up cardiovascular endurance and muscle strength. Yoga and pilates are also great ways to engage the body without upsetting the gastrointestinal tract. 

In reality, IBS patients don’t have to avoid HIIT and muscle training altogether. It’s possible to create versions of the exercise that are easier on the body. Instead of doing compound weightlifting exercises such as squatting and deadlifting, IBS patients can focus on higher repetitions with lower weights instead of shocking the body with powerful movements. 

4. Watch Your Eating Habits

Discomfort from diarrhea and constipation can shape the way we eat. For instance, in order to prevent frequent bowel movements, patients may eat two big meals and not eat for the rest of the day. Patients could also decide to skip meals altogether because of abdominal pain, which could eventually result in overeating. 

Knowing how symptoms shape eating habits is key in managing weight for IBS, as well as other gastrointestinal disorders. 

Read more: What Makes Irritable Bowel Syndrome Worse? 

FODMAP Diet and Other Food Recommendations


Food is a known trigger of IBS. This makes it difficult for IBS patients to find suitable meal choices while maintaining their weight. The problem is that some foods which contribute to weight loss can lead to symptom flare-up. These foods include:

  • Legumes: Beans are a great source of protein and fiber, but could prove problematic for IBS patients. Beans can lead to an increase in stool bulk, leading to worse episodes of constipation. 
  • Dairy: Foods high in fat including dairy are typically not recommended for IBS patients. It’s because dairy products such as milk and most types of cheese contain lactase. This enzyme may be lacking in IBS patients, leading to indigestion and diarrhea. 
  • Gluten: Wheat and rye are often recommended to people hoping to lose weight because these components are hard to digest, which can keep a person full longer. On the other hand, IBS patients can be more sensitive to gluten compared to healthy individuals, leading to abdominal cramps and discomfort. 

Although these foods tend to produce negative effects in general IBS cases, not all individuals will respond the same way. Before banning certain foods from your diet, we recommend keeping a food diary so you can keep track of the effects foods have on your gastrointestinal system. 


IBS patients tend to share the same sensitivity to gluten as people with coeliac disease. What was once thought of as a non-coeliac gluten sensitivity turned out to be an intolerance for a specific chain of carbohydrates called FODMAPS. 

FODMAP stands for fermentable oligosaccharides, disaccharides, monosaccharides, and polyols. These components are found in foods in the form of fructose and lactose, to name two, and can be found in both organic and synthetic foods. 

Nutritionists believe that adopting a low FODMAP diet is the key to a better lifestyle for IBS patients. By lowering FODMAP intake, patients reduce the risk of bacteria fermentation in the large intestine, which can significantly improve bouts of gassiness and constipation. 

How Long Should Patients Eat Low-FODMAP Foods

If low FODMAP foods are useful in managing symptoms, then how come nutritionists don’t recommend going on a low FODMAP diet forever? 

This is because high FODMAP foods can also be instrumental in managing IBS. Those included in the high FODMAP list such as garlic, for example, have strong antibacterial properties that could keep infections away. 

More importantly, not all high FODMAP foods produce adverse reactions in patients. It doesn’t make sense to completely eliminate high FODMAP foods in your diet, especially since some of these have high nutritional content. 

Recommended Diet For IBS Weight Loss 

We recommend starting out with a low FODMAP diet. After 2-3 weeks, start reintroducing high FODMAP foods in your diet in order to understand how each food affects your body, if at all. 

The following are low in calories and also considered low FODMAP foods:


Chicken, beef, lamb, pork, turkey, fish. We recommend sticking with chicken and fish since they have the lowest calories per serving size.

Fruits and Vegetables

Zucchini, potato, cucumber, eggplant, green beans, lettuce, bean sprouts, carrots, blueberries, orange, passion fruit, pineapple, rhubarb, strawberry, grapes, lemon and lime, guava. 

Other fruits and vegetables have to be consumed in limited servings to remain low FODMAP. These are: broccoli (up to ½ cup), corn (half a cob only), tomato (up to 4 small pieces only), cranberry (1 tbsp). 


Look for gluten-free and wheat-free alternatives. Breads such as corn bread and oat bread are also good alternatives. Brown rice and white rice are generally acceptable. Oats are also considered a great source of fiber, while keeping your diet low in calories.

Tools like MyFitnessPal and CalorieKing are useful in keeping track of your calorie count. You can choose to build your daily meals around certain calorie counts. The 1,500 – 2,000 range is sufficient for most average-size adults. Ask a nutritionist for more in-depth advice on a healthy caloric range. 

Exercises For IBS Weight Loss

women in pilates studio

Doesn’t Exercise Stimulate Symptoms?

Yes, exercise can stimulate the gastrointestinal system and produce reactions. But this doesn’t mean that all forms of exercise are bad for IBS patients. In fact, research shows that regular exercise can help with IBS symptoms. Even 20 to 30 minutes of exercise three times a week is already useful in improving a person’s quality of life. 

Low-intensity exercises such as swimming, yoga, and pilates are perfect for burning fat without stressing out the gastrointestinal system. Just like food, it’s important to test out which physical activities result in aggravated symptoms so you don’t end up eliminating all of them. 

What Exercises to Avoid

Below are the top three exercises to avoid when you have IBS:

  1. HIIT: HIIT workouts are purposefully intense to keep your heart rate up. Unfortunately, your digestive system might interpret this as stress and trigger IBS symptoms. It’s still possible to do an interval training circuit without the jumping and running. Eliminate exercises that require quick bursts of movements and stick to those that are easy on the body. 
  2. Weight Training: Swimming isn’t the only form of exercise available to you. If you want to keep training your muscles, you can use lighter weights instead of heavy weights and machines instead of freehand weights. The point is to reduce the stress on your body 
  3. Running: Running and even jogging can irritate your stomach and affect your gastrointestinal system. Consider brisk walking or taking a route that has an incline so you can still work up a sweat. 

Manage Your IBS Gain Weight

Just because you have IBS doesn’t mean you have to deal with the extra weight. At Gastro Center in New Jersey, we find ways to improve your lifestyle as a person with IBS.

With our proactive methods, we can create a diet and exercise plan that fits your needs. Get in touch with us today.