6 Reasons Why You Might Be Gaining Weight with IBS

Weight Gain and IBS

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IBS is not a health condition that causes weight loss. However, things that you are doing to try to cope with your IBS may be causing you to put on unwanted weight.

As you probably know, excess weight increases your risk for many chronic and serious health problems, including some cancers, dementia, diabetes, gallbladder disease, heart disease and osteoarthritis. Therefore, it is important to take a look at any lifestyle habits that you may be engaging in that can cause weight gain. In the following slides, we will look at some things that you may be doing for your IBS that are inadvertently contributing to weight gain. You will also find some suggestions for making changes that will help both your IBS and your waistline.

1. You Are Eating Too Many Refined Carbohydrates

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Many people who have IBS turn to crackers and white rice because they seem like "safe foods", however these foods tend to be high in refined carbohydrates. Diets high in refined carbohydrates have been associated with weight gain. Refined carbohydrates include things like sugar, high fructose corn syrup, white flour, corn flour and white rice. These carbs can be found in bread, pasta, pastries and other sweets, and in unexpected places like condiments, sauces and salad dressings.

People who have IBS tend to choose foods such as crackers because they seem like they are easier on the system. There is a method to this madness as these refined carbs are quickly and almost completely digested higher up in the digestive tract and thus have a lessened impact on the bowels. Unfortunately, there are two major problems with this strategy:

1. Weight Gain: Because they are quickly digested, glucose from refined carbohydrates hits the bloodstream very quickly, triggering an insulin response. In an oversimplified explanation, insulin needs a place to store all of this glucose and the two places that it has available are your fat cells and your blood vessels, leading to excess weight and clogged arteries. Insulin does such a good job cleaning out the glucose that it causes an energy crash several hours later, causing you to crave more carbohydrates and thus the cycle repeats itself all over again.

2. Dysbiosis: Diets high in refined carbohydrates have been found to be associated with unfavorable bacterial balances in the gut. Dybiosis can result in symptoms of gas, bloating, and chronic diarrhea and constipation - in other words, IBS symptoms. Therefore the crackers and rice that seem like "safe foods" may only be feeding the problem.

What to do instead?

Instead of carbohydrates, think of protein and healthy fats. Protein is easily digested and thus can become your new version of a "safe food." And you no longer need to subscribe to the old notion that "fats make you fat." Instead, healthy fats help to slow down the insulin response and make you feel more satisfied after and in between meals and may help to promote a healthier balance in your gut bacteria. Later in this slideshow, you will find links for articles to help you to choose foods that are healthier than refined carbohydrates.

2. You Are Eating Too Many Gluten-Free Processed Foods

Gluten free pastries
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Many people who have IBS have found that their symptoms are lessened if they follow a gluten-free diet. This can be a very helpful strategy for minimizing IBS symptoms, but can lead to weight gain if one is not careful. The problem lies in the fact that many producers of gluten-free products have replaced gluten with added sugar and other refined carbohydrates. As you learned in the last slide, high levels of refined carbohydrates can lead to weight gain.

What to do instead?

Avoid processed gluten-free snack foods, sweets, breads and pastas. Instead, fill your plate with protein, healthy fats, vegetables and fruits - all naturally gluten-free foods. If your body can tolerate grains, you can begin to experiment with some new gluten-free grains.

3. You Are Not Exercising Enough

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It can be hard to commit to a regular exercise routine when you have a digestive system that is unpredictable. Who wants to get on the treadmill when you feel like someone is stabbing you in the stomach?

That being said, exercise is good for your overall health, your digestive health, and for weight loss.

What to do instead?

Try to do something physical every day. On your worst days, that might just mean doing some yoga stretches in front of the television. However, on your better days, try to walk, run, dance, stretch and/or lift weights. Find a way to move your body that you enjoy and make it part of your regular routine. You may find that having workout equipment or exercise tapes at home are two good workarounds for exercising in spite of your IBS.

4. You Are Skipping Meals

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Many people who have IBS skip meals in an attempt to prevent IBS symptoms from ruining their plans. This is a mistake for a couple of reasons:

1. Your digestive system doesn't stop moving just because you haven't added new food to it.

2. Skipping meals can lead to eating excessively at your next meal. Being extra hungry can also leave you at risk for choosing foods high in unhealthy fat or refined carbohydrates. Excess eating and poor food choices could be adding to your weight gain.

What to do instead?

Try to eat your meals on a regular basis. This will help to keep your inner body clock, your digestive system and your metabolism regulated. You may find that your digestive system prefers four smaller meals rather than the more typical three-meals-a-day habit. If you are looking for a little extra insurance when you have a big day in front of you, reach for foods high in protein or foods that are not as likely to cause intestinal gas.

5. Your Gut Bacteria Is Out of Whack

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Gut bacteria are the microorganisms that populate your intestinal tract. In an ideal state, your gut is populated with more "friendly" bacteria and less "unfriendly" bacteria. However, things like stress, antibiotic use, and poor diets can have a negative impact on the balance of your gut bacteria, leading to the state of dysbiosis that we talked about in a previous slide. This imbalance can lead to a variety of symptoms and health problems, but for the purpose of today's discussion, there are two reasons why your gut bacteria are important:

1. Imbalance in your gut bacteria can be contributing to your symptoms of pain, gas, bloating and motility problems.

2. A new focus of research has to do with the role of gut bacteria in the onset and maintainence of excess body weight. It is theorized that an imbalance in gut bacteria may interfere with body signals for hunger/fullness, may increase inflammation, which in and of itself is related to obesity, and may lead to insulin resistance, which is also associated with obesity.

What to do instead?

Luckily, the things that are good for the balance of your gut bacteria are also things that will help you to lose weight. As we already have discussed, significantly reduce your consumption of refined carbohydrates and unhealthy fats. Eat more produce - your friendly gut bacteria love their veggies! If you are concerned that eating vegetables and fruits will trigger your IBS, start with those that have been found to be low in FODMAPs. FODMAPs are carbohydrates that have been found to contribute to symptoms in people who have IBS. Once your body has adjusted to your increased produce intake, you may be able to expand your range.

6. You Are Taking an Antidepressant

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Many people who have IBS take an antidepressant medication not necessarily because they are depressed, but because certain antidepressants have a beneficial effect on IBS symptoms. However, some antidepressants can cause weight gain. Often this side effect is not that pronounced, but in some cases, the medication can have a notable impact on your waistline.

What to do instead?

Talk to your doctor. See if there is an alternative medication that is less likely to affect your weight. If not, you can take advantage of all of the other strategies that have been discussed throughout the previous slides.


Hawrelak, J.A. & Myers, S.P. "The Causes of Intestinal Dysbiosis: A Review" Alternative Medical Review 2004 9:180-197.

Hur, K. & Lee, M. "Gut Microbiota and Metabolic Disorders" Diabetes & Metabolism Journal 2015 39:198-203.

"Managing Overweight and Obesity in Adults" National Institute of Health Systematic Evidence Review from the Obesity Expert Group 2013.

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