Is SIBO to blame for your unexplained weight gain?

If you’ve gained weight recently, your first reaction may have been to spend more time at the gym or eat a bit healthier. You may cut back on certain foods, watch your sleeping habits, and try to manage your stress. 

If nothing you’ve tried seems to be working, it’s hard not to panic. It can be incredibly frustrating to feel like your body is out of your control. However, there may be a gut health condition at play here, especially if your weight gain has coincided with digestive symptoms like bloating or feeling full. You may be struggling with Small Intestinal Bacterial Overgrowth (SIBO), a condition that plagues more than 70% of those diagnosed with Irritable Bowel Syndrome (IBS). 

What is SIBO?

SIBO occurs when an excess of bacteria typically located in the colon infiltrates the small intestine. This intrusion disrupts normal digestion, leading to an array of uncomfortable symptoms.

There are three types of SIBO based on three different gasses that these unwanted bacteria produce in the small intestine. These are hydrogen SIBO, methane SIBO, and hydrogen sulfide SIBO.

SIBO Symptoms

Bloating is the main complaint from SIBO patients, often accompanied by increased gas and abdominal discomfort. These symptoms often intensify post-meals. Nausea is common as well, along with irregular bowel movements that may stay consistent or alternate between constipation and diarrhea.

However, SIBO can also cause seemingly unrelated symptoms, like brain fog, joint pain, or unexplained weight gain. 

SIBO and Weight Gain 

SIBO, and especially methane SIBO, can often be culprits of unwanted weight gain. This can be for many reasons. 

Inflammation and Gut Immune Response

When you have SIBO, your inflammatory response will go off, putting your body into an “emergency state”. When you’re in an emergency state for too long, your body is putting less energy into your metabolism, slowly it down and allowing for your body to retain more calories. 

Methane Gas Archaea

The “bacteria” behind methane SIBO actually isn’t bacteria; it’s archaea. Archaea assists your body in breaking down certain compounds in food that your body normally can’t, therefore helping your body to absorb more calories than it normally would per meal. 

Slow Motility

SIBO slows down your gut motility and Migrating Motor Complex, which sweeps through your digestive system every time you don’t eat for a few hours to clean it out. With these not working properly, your body has more time to absorb calories each time you eat a meal. 

What to Do Next

If you suspect you may have SIBO that’s contributing to unwanted weight gain, it’s time for you to take a SIBO breath test. The SIBO breath test is the most accurate way to diagnose SIBO and figure out which type of SIBO you may be struggling with. You can do a breath test at your practitioner’s office or in the comfort of your own home with at-home tests. If you’re looking for more information about the SIBO breath test, download our free ebook, Our Ultimate Guide to Testing for SIBO, all about testing and test interpretation.

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