If you have already been diagnosed with small intestinal bacterial overgrowth you might be wondering so many things, including: Will I lose weight after SIBO treatment?

Despite the fact that I have already written a ton on SIBO for SIBO patients, I still get questions daily on it. And I like that about you! You are always curious and inquiring, and I am more than happy to share. 

If you search SIBO on agutsygirl.com, you’ll find pages upon pages filled with information.

But if not, then this is your place.

pssst…..the brand new version of Reasonable SIBO has released. Get your copy today!

Will I Lose Weight After SIBO Treatment (full SIBO Q&A with A Gutsy Girl)

Click HERE to save this post on will I lose weight after SIBO treatment for later.

Will I Lose Weight After SIBO Treatment (full SIBO Q&A with A Gutsy Girl) agutsygirl.com #SIBO #guthealth

Below you will find my current master list of SIBO Q&A.

Please make note that this is not an exhaustive list.

If you have your own SIBO-related question, please leave it in the comments below so I can address and add it to this post.

Weight Gain as a Result of SIBO

To start….let’s talk about the weight gain so many get frustrated by and address the question, “Will I lose weight after SIBO treatment?”

Recent research has linked methane gas production to the pathogenesis of constipation and irritable bowel syndrome (IBS), as well as obesity. (source)

From my research, methane dominant SIBO correlates with weight gain more often for these 3 reasons:

Slower Transit Time

I’ve talked about this at length in various places, but there is a correlation between slow transit time and methane production.

Slow transit time means there is a slow movement of food, food which sits in the gut for far longer than it should, causing many problems, including weight gain.


Archaea have been shown to affect the amount of calories your body absorbs by increasing the capacity of gut bacteria to digest specific glycans. (source)

What does that mean? Yet again, a calorie is not a calorie.

“So let’s say you have a high-fiber diet. Humans generally can’t eat fiber. Cows and ruminating animals have a lot of methanogens because the methanogens help facilitate digestion of fiber. So what does that mean? That means that you can get more calories from a meal if you’re a methane producer because you’re liberating calories from things that people who don’t have methane can’t get.” (source)

Sluggish metabolism

Metabolism impacts HOW your body is able to utilize the nutrients it receives from food. 

With a slow metabolism, your body is not able to efficiently use nutrients from food, so the excess is often stored as fat. 

A slow metabolism and sluggish gut transit can also negatively impact some of our natural hunger hormones, such as leptin and insulin, which can keep us from staying full and cause further weight loss resistance. A vicious cycle, isn’t it? (source)

How to Lose Weight with SIBO (The SIBO Weight Gain Connection) agutsygirl.com #SIBO #weightgain weight gain causes

Losing the weight after treatment

So the question is,

Will I lose weight after SIBO treatment and addressing the overgrowth of bacteria + clearing it?

The answer is, “Yes,” but keep in mind these things:

  1. Completing SIBO treatment after a SIBO diagnosis doesn’t mean the bacteria is truly gone and everything goes back to “normal,” necessarily. A lot of people simply do a treatment plan without understanding their root cause and ultimately while short term relief might be felt, the lasting effects aren’t there.
  2. You might not have truly needed to lose weight to begin with? Perhaps the “weight gain” you felt was simply just a lot of bloating and constipation vs true body fat. Healthy weight is unique to the individual, but according to the Set Point Theory, once (truly) healed, your body weight will go to where it naturally desires.
  3. If you have any other underlying medical conditions, this could prohibit the weight loss as well. Be sure you know all risk factors for any underlying condition that could also be present.

Do you think antibiotics were the most important factor in clearing your SIBO?

Yes and no.

Yes because, for me, without them the initial small intestine bacterial overgrowth was not likely to go away on its own.

I tried both a stringent short-term diet and the natural antibiotic route; I could never fully get rid of it.

And guess what? Those routes won’t always get rid of SIBO for everyone. 

No shame in Rifaximin and/or Neomycin and/or another antibiotic to help rid the overgrowth on your SIBO journey.

That said, the antibiotics played no part in keeping it gone for good. That was 100% lifestyle changes.

What are the most common symptoms of SIBO?

These are the most common symptoms:

  • bloating
  • diarrhea
  • constipation
  • undigested food in stool
  • pain
  • B12 deficiency
  • rashes
  • fatigue
  • food sensitivities
  • dark circles around eyes
  • hypersensitivity
  • headaches
  • all of the above (ugh, the dickens!)

That said, here were some other things for me personally:

  1. acne
  2. IC valve protrusion
  3. punch in the stomach feeling
  4. absolutely famished feeling

How do you know if you have SIBO / what type of SIBO it is?

The way you know is by getting tested since the types of bacteria present do matter

Then, once you get tested, your levels will tell you if you’re methane, hydrogen (or both) dominant.

A word of caution, though, most current SIBO tests do not detect a hydrogen sulfide dominant form of SIBO.

Here are some resources on agutsygirl.com for knowing if you have SIBO and what kind it is:

  1. How to Do the SIBO Breath Test
  2. Beginner’s Guide to Digestive Health Testing
  3. Do You Smell Like Rotten Eggs

Just found out I have SIBO. Started antibiotics recommended by my doctor. Now what?

Great question! I think my 28-Day Rifaximin and Neomycin SIBO Journal will help. 

Additionally, there is a lot of controversy over what we should be eating while on the antibiotic(s). You’ll see in my journal above that I have done it all – no FODMAPs, low FODMAP diet, all the FODMAPs. 

I do not think that doing the full course of antibiotics FODMAP-free with super restrictive diets are the answer. 

In fact, I did that during round one (I’ve done four rounds total), and it clearly was not the right answer; I relapsed fairly quickly.

I believe the answer is that you must eat some FODMAP foods, even though it will not make you feel great. In fact, I felt miserable. But I believe, deep down, that by eating FODMAPs as much as you can tolerate is best for the long run.

Again, though, everyone is different. I just learned to trust the process.

Does Atrantil help to get rid of Methane SIBO?

In 13 Natural Antibiotics for SIBO I stated,

According to Atrantil, “It is formulated by a board certified gastroenterologist to naturally and safely disrupt the the methane production by removing the unwanted bacteria from the small bowel and send them to the colon, where they belong.”’

I did use Atrantil, for the record. 

Many have great success with it, some do not.

(If you want to try Atrantil, you can use code AGUTSYGIRL at checkout to save 10%.)

Also, many take it in addition to the antibiotics and/or other herbal supplements.


Someone asked, 

Small servings of cooked broccoli are low-FODMAP, but why does it give me so many tummy problems?

First, ask yourself if this is exactly how you’re eating the cooked broccoli (in these quantities).

broccoli heads FODMAP SIBO agutsygirl.com #broccoli

If your answer is, “No,” then try no more than 3/4 cup to see how you do.

But if the answer is “Yes,” then consider these things:

  1. What else are you eating with the broccoli? Other high-FODMAP foods? Maybe it’s just an overload.
  2. What is your emotional state while eating the broccoli? If you’re stressed about it going into the meal, your body knows, can, and will react. Remember, how you eat is many times as important as what you eat.
  3. Have you tried taking a digestive enzyme before eating it?
  4. Are you eating the broccoli heads or stalks? There is a difference.
broccoli stalks FODMAP SIBO agutsygirl.com #broccoli #SIBO

(Broccoli images taken from Reasonable SIBO.)

What happens if you are on a SIBO protocol and eat something high FODMAP?

Nothing. You just keep moving forward as if you had not eaten anything high FODMAP. The more you stress about it and dwell on it, the more it will impact your digestive system.

A SIBO protocol or even being on SIBO diets doesn’t mean you must be 100% compliant.

You deal with it and move forward.

Do antibiotics temporarily or permanently damage the gut?


But if taken chronically, then more damage happens over time.

That being said, the good news is that SIBO antibiotics stay localized to the intestines.

They are almost completely non-absorbable which means they stay in the intestines, having a local action and don’t cause systemic side effects, such as urinary tract infections. (source)

However, after any course of antibiotics, there are things you can do to make sure your gut flora is thriving.

What to eat when everything, even healthy things, hurt your stomach?

This is a very common question since SIBO symptoms are fierce.

My best suggestion is to go back to the drawing board.

  • Why is everything hurting your stomach?
  • Is it for sure SIBO?
  • Anything else?
  • Have you been keeping a detailed food journal?

cannot stress enough the importance of keeping a detailed food journal which tracks not only dietary changes and digestive systems, but also tracks your day-to-day lifestyle; sleep, bowel movements, triggers, workouts, etc.

This is why I created my gut healing journey journal – for you – for this community.

If you still react to high FODMAP foods after treatment, does that mean you still have SIBO?


But also keep in mind how much of said food you’re eating. 

Just because you clear SIBO doesn’t mean you can eat 5 cups of raw broccoli. 

Think practically.

If a food become high FODMAP at 1/2 cup and you’re eating a smidge over that, perhaps the overgrowth has not cleared itself.

Also, you can test foods at home now with the FoodMarble AIRE device + app.

Learn all about it HERE.

Do I have SIBO or just a lactose intolerance?

Again, this is one you’ll have to work closely with your healthcare provider on. 

If you’ve been keeping a meticulous food and lifestyle journal, s/he will have a much better idea if your digestive symptoms are pointing more towards SIBO, a lactose intolerance, and/or anything else.

You can test for lactose via the FoodMarble AIRE device + app I shared above as well.

FoodMarble AIRE device SIBO agutsygirl.com #foodmarble #SIBO

Can you tell me more about the Elemental Diet?

The elemental diet is a liquid diet which contains every nutrient needed for survival, but in the simplest form,; pre-digested, and making digestion easy for the gi tract.

It contains fats, carbohydrates, and amino acids (the building blocks of protein), in addition to multiple vitamins you would usually receive through food. Consuming these nutrients in their pre-digested form starves the overgrowth of gut bacteria and causes it to die.

The estimated success rate for two weeks is about 80% compared to a success rate of only 49.5% with antibiotics. The large difference in these two statistics was a big factor in convincing myself the elemental diet was worth a try.

The use of an elemental diet is a temporary diet.

We have an entire post on a DIY Elemental Diet for SIBO that you can read about HERE.

I know there are far more questions, so please, ask away in the comments below.

If you liked this post on will I lose weight after SIBO treatment, you might also enjoy:

  1. Printable SIBO Diet (Reasonable SIBO, Heal Your SIBO)
  2. Best Supplements for SIBO {based off experience + research}
  3. SIBO vs IBS {and a SIBO Q&A with Dr. Nirala Jacobi}


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  1. What fodmaps did you eat? And did you do strict meal spacing and intermediate fasting? What was a typical day of eating for you?

  2. There are several different SIBO tests. I think I have methane dominant SIBO. Will all of the tests listed give me the result or is one better than the other?

  3. Thank you so much for this information, Sarah. I truly appreciate it as a navigate digestion issues. Question for you, I just got my results back from the GI MAP test. Did you have this done? I am wondering if there are markers on this test that could be indicative of SIBO. I’ve hit so many walls with my treatment and am wondering if Rifaximin could be what I need to kick these gut issues I’ve had for over a decade.

  4. Did you find Atrantil helpful? Do you do the maintenance dose of it as I heard them discussing this in a recent podcast with Chris kesser. When did you incorporate HCL? After sibo meds? I’m on my third round of meds and feeling pretty awful. The doctor said after this round to take out garlic and onion and other fod maps but not to be extreme. I don’t feel like that is super helpful and want to be prepaid for after this round of medication. Open to trying HCL, a motility med or Atrantil. Thank you for all of your great info!

  5. Which is more effective method to get rid of sibo either Rifaximin/neomycin or the elemental diet that you drink for 2 or 3 weeks that’s created by Allison Siebecker?

  6. I have done two rounds of natural antibiotics and Sibo keeps coming back. I am seeing a naturopath so I’m waiting to see what my next step will be. My biggest symptom is my stomach bloat. It’s so uncomfortable it feels like my stomach is going to explode. Any tips to help with the bloat?

  7. Hi Sarah, I have had gut issues for 10 years and despite seeking out numerous professionals to get to the bottom of it (pardon the pun), I have only now been diagnosed with SIBO. I’ve suspected it for years as there have been several times I was put on strong antibiotics for other things (sickness, post c section, gastro etc) and symptoms reduced only to return a few weeks later (which makes me think it has reoccurred already several times). I have exactly what you did- mixed type but all symptoms alike methane dominant and my archaea is very high via ubiome testing. The weight gain is annoying despite a very healthy diet but what’s most frustrating is the lack of weight loss when I exercise daily and cut calories. When I read your blog sibo- weight gain connection it all made sense and I feel my sibo mimicks yours! Just wondering where I can start with your resources and how to access your blogs to follow what you did to heal? I’m currently on a herbal gut protocol and felt instantly better (and lost 1 kg in the first week) but after 2 weeks on the protocol, my bloat has returned and the constipation. Did you have symptom relapse even whilst eradicating and on a protocol? I was never told to eat a certain way, just to Avoid all highly processed white flour goods, candies, cakes, pies, table sugar,honey, rice malt, maple syrup,and soft drinks, to avoid snacking, to avoid alcohol and to not eat foods that I know cause symptoms. Thanks for your info and help. Chloe

  8. Hi. I wondered how long you had symptoms of SIBO before being diagnosed and then treated with antibiotics. I’ve been bloated for about 14 months and was diagnosed three months ago. I had one round of Xifraxin which didn’t work, then tried the antimicrobials, including Atrantil. Those didn’t work either. I also tried the low FODMAPand SIBO Bi-Phasic diets and found not symptom improvement with either.Now I will be starting a protocol of Xifraxin and Neomycin and I’m excited but trying to not to get my hopes up. Your journaling of your experience with this combination of antibiotics is very helpful.

    1. Hi Denise! I think I went undiagnosed for YEARS! This is also why I think it took me so long to get rid of it. Good luck with the antibiotics. They absolutely worked for me 🙂

  9. Maybe you can help me, please. I’ve been bouncing from one doctor to another, hospital to hospital. On paper I seem fine. I’ve had maany tests done. No one can help me. Stuff I struggle with the most:
    – LOTS OF GAS, sometimes it’s trapped and I get bloated, sometimes I pass wind all day/night long… literally, so much of it.
    – Nausea, and eventually vomiting. It doesn’t seem to correlate with anything I eat. It generally seems that when I’m gassy, especially when it’s trapped, I get nauseous, but not always
    I’ve been tested for candida, parasites, coeliacs & crohns (blood tests, gastroscopy 2x, colonoscopy once), food intolerances, breath test for glucose, thyroid hormones – a bit low but not significantly, vitamin d3 – again, a bit low. But overall, nothing wrong.

    Lactulose hydrogen breath test: I started with 8ppm at 1:53pm, at 2:33pm it was 22ppm, 2:53pm – 50ppm, at 3:13pm it reached 104 ppm. I hit the peak at 4:13pm with 149ppm. I was diagnosed with sibo, got a few rounds of xifaxan, did not help at all. Unfortunately the test didn’t measure methan. [Photo of my breath test results: https://ibb.co/CKGdfd3%5D

    Currently I am taking mirtazapine which I will stop because for the entire duration (2 months) I’ve been having vivid nightmares nearly each night, waking up 2-3 times per night.

    My current doctor said she doesn’t suspect sibo because xifaxan didn’t help. Instead she prescribed me probiotics. It doesn’t help. I don’t know what to do anymore. I am 23 and I have no life because I barely leave house due to my issues. I’m becoming very depressed and I hold no hope in doctors anymore

  10. How soon did you start introducing probiotics after the antibiotics? Do you have any tips for the days/weeks after antibiotics? Your journal is really helpful!

  11. I have had undiagnosed SIBO for about 3 years. I have been (mostly!) LOW-FODMAP for 8 months. I just finished my second round of Rifaximin. I felt like the first round helped with the consistency and regularity of my movements but I don’t feel like the 2nd round did anything. I have been trying to slowly reintroduce foods with no luck. I still have bloating/diarrhea/gas. I remained on the LOW-FODMAP diet throughout both rounds. What would your next step be? I know you had 4 rounds of antibiotics. Do you recommend I take a prokinetic now? I feel like motility is generally fine. I have been taking a probiotic, and atrantil as needed. I am feeling a bit discouraged and would appreciate any guidance you have. I am a bit skeptical of intermittent fasting but of course will be willing to try if that is you recommendation. Thank you!

  12. If I suspect SIBO do I need to be treated in order for it to go away or can I start thrive probiotics and hope that will do the trick?

  13. Are prokinetics the key? I have tried antibiotics and my results so far have been very frustrating. I relapse very quickly! I think I sould move on Prokinetics.

  14. My functional medicine practitioner has given me candicid forte for 4 weeks. Is that enough to kill bad bacteria’s? Of course I am dairy free Keto too

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