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Diarrhea after bariatric surgery? Here's what you can do about it

Having bariatric surgery has an impact. Apart from losing weight, a lot happens to you mentally and emotionally. Your body also needs to adapt. One of the changes is that the surgery reduces your intake of vitamins and minerals, which can affect your bowel movements. As a result, diarrhea is common after weight loss surgery. Find out the reason for diarrhea and ways to combat it. 

What is diarrhea?

Diarrhea involves thin stool. Your large intestine extracts moisture from your stool to keep you from dehydrating. If stool stays too short in your intestines, your colon does not have time to extract the moisture. As a result, your stool is moist and thin when it leaves your body. In short: you have diarrhea. 


How to recognise diarrhea?

  • Your stool is very thin
  • You need to go to the toilet several times a day
  • You have a sudden urge to go to the toilet
  • You have difficulty holding your stool
  • You experience abdominal pain or cramps


What causes diarrhea after bariatric surgery?

Because of your stomach reduction, your digestive system has changed. This makes it more difficult to absorb and digest food.


In the case of a Gastric Bypass you no longer have a pylorus. The pylorus is the sphincter between the stomach and the small intestine. While your stomach kneads the food liquid, the sphincter remains closed. Only when food is finely enough, the pylorus opens occasionally to let small pieces of food enter your small intestine. Without a pylorus, food goes into the small intestine too quickly and all at once. We call this early dumping. Your small intestine takes over from the stomach and keeps adding fluid to the food to liquefy it. As a result, your intestines become full and bloated. This can cause diarrhea. 


You may also suffer from a virus or bacteria, caused by infected or spoilt food, for example. Your intestines work hard to get the invader out of your body via stool. If this happens, you have acute diarrhea. This usually does not last long. 


What can you do in case of diarrhea after bariatric surgery?

1. Eat enough fibre

Fibre absorbs moisture, similarly to a sponge. If you have diarrhea, fibre helps absorb the excessive fluid, making your stool less thin. This is why it's so important to get in enough fibre even when you have diarrhea. You can fibre in vegetables, fruit, whole grain products, legumes, potatoes, nuts, and seeds.


Struggling to eat enough fibre after your surgery? Take Fibre supplements to add to your diet. This will increase your daily fibre intake and help maintain your gut health. 


Do you eat more fiber than you're used to? Or do you consume more than 20 grams of fiber per day? The advice is to gradually increase fiber intake and spread the amount of fiber throughout the day.


2. Stop taking fruit juices

Fruit is packed with nutrients and is incredibly healthy. Which is why the advice is to eat at least 2 servings of fruit a day. However, fruit also contains sugars. If you take in too many sugar, the amount of fruit sugar in your intestines becomes too high. The fruit sugar will then attract moisture. This makes your stool thinner and may cause diarrhea.


Right after your surgery, you’ll eat liquid and finely pureed products before returning to solid food. We understand why you choose fruit juice instead of fruit. Yet fruit juices contain a lot of fruit sugar. Avoid them as much as possible if you suffer from diarrhea. 


3. Limit sweeteners

Your intestines hardly absorb certain sweeteners. They enter the colon where they attract moisture. This can cause diarrhea. For this reason, it is wise to limit food and drinks containing sweeteners if you’re having diarrhea. 


Need more help?

Want to know more about diarrhea after bariatric surgery, nutrition, or your health? Our dietitians are happy to help. Reach out to us here or book a free personal consultation.


Are the tips above not helping? Having persistent diarrhea after your surgery and does it last longer than 2 weeks? If so, please contact your doctor. 


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