Traditional SIBO, also known as Small Intestinal Bacterial Overgrowth, occurs in the small intestine and is characterized by bacterial overgrowth. The harmful bacteria produce excess amounts of hydrogen and methane gas, which leads to a wide range of gut health issues.

Hydrogen sulfide is a gas produced by certain types of bacteria, including those involved in small intestinal bacterial overgrowth (SIBO). Hydrogen sulfide SIBO, also known as hydrogen sulfide-positive SIBO, is a specific subtype of SIBO where bacteria predominantly produce hydrogen sulfide gas instead of other gases like hydrogen or methane.

Unfortunately, most SIBO breathe tests don’t account for or detect a third harmful gas that could result in other, more unique symptoms — hydrogen sulfide gas. This causes something known as hydrogen sulfide SIBO, which requires a unique treatment when compared to traditional SIBO.

What is Hydrogen Sulfide SIBO?

Hydrogen sulfide SIBO is characterized by a specific type of bacterial overgrowth — also known as sulfur-reducing bacteria — that results in excessive hydrogen sulfide gas in the small intestine. Hydrogen sulfide refers to a specific type of small intestinal bacterial overgrowth (SIBO) in which the predominant bacteria in the small intestine produce hydrogen sulfide gas- think egg like smell.

Hydrogen sulfide is a gas produced by certain types of bacteria, including Sulfate-Reducing Bacteria (SRB). These bacteria utilize sulfur compounds as energy sources and convert them into hydrogen sulfide gas. When an overgrowth of these SRB occurs in the small intestine, it leads to hydrogen sulfide SIBO.

Gut Bacteria that Produce Hydrogen Sulfide

In the gut, hydrogen sulfide (H2S) is primarily produced by sulfate-reducing bacteria (SRB) and certain other bacteria involved in protein and amino acid fermentation.

The main types of bacteria responsible for H2S production include sulfate-reducing bacteria. These bacteria are capable of fermtning amino acids cysteine and methionine.

Hydrogen Sulfide Bacteria include

• Desulfovibrio species
• Bacteroides
• Enterobacter
• Morganella
• Staphylococcus aureus
• Klebsiella
• Proteus
• Fusobacterium.

Symptoms & Causes of Hydrogen Sulfide SIBO

Hydrogen sulfide gas is known to be toxic and can have detrimental effects on the body. It can cause gut inflammation, damage the lining of the intestines, and impair nutrient absorption(*). This can lead to a variety of digestive symptoms, such as bloating, abdominal pain, diarrhea, malabsorption issues.

The most common symptoms of hydrogen sulfide overgrowth in the small intestine include belching, and flatulence that smells like rotten eggs. Other symptoms include bladder pain, joint pain, brain fog, constipation, bloating, cramps, difficulty breathing, and abdominal pain(*).

Sulfur sensitivity can also be caused by a mutation of the cystathionine beta-synthase (CBS) gene and/or well water that contains high amounts of sulfur(*). Once sulfur starts to build up in the body, it could welcome certain bacteria that produce hydrogen sulfide by breaking down sulfur.

A Low-Sulfur Diet for SIBO Symptoms

If you’re experiencing hydrogen sulfide SIBO, work with  a Certified Functional Medicine Doctor. As part of the treatment process, its often recommend you follow a low-sulfur diet for 4-6 weeks to provide symptom relief. The goal is to reduce sources of dietary sulfur to retain a healthy balance of friendly bacteria in your gut — which is essential to a happy and healthy life.

In order to find success with a low-sulfur diet for SIBO, you’ll want to first eliminate all sulfur-rich foods from your diet. If you start to feel better, you can slowly start to re-introduce those foods into your diet. If you notice your symptoms return, you’re likely suffering from sulfur intolerance.

Sulfur- Rich Foods to Avoid If You Have Hydrogen Sulfide SIBO

Believe it or not, sulfur is found in a lot of the foods you eat on a daily basis. In fact, it’s the third-most-common mineral found inside the human body. That means you’ll have to avoid a lot of different foods when following a low-sulfur diet, which might seem difficult to accomplish.

For example, you’ll need to avoid most animal proteins (red meat, white meat, dairy products), since they contain amino acids cysteine and methionine — which both contain sulfur. You’ll also need to avoid sulfur-rich dried fruits, allium vegetables, cruciferous veggies, and sulfur additives.

Here’s a quick list of some of the foods that contain high amount of sulfur- things you might need to avoid:

• Vegetables to avoid: Arugula, asparagus, bok choy, brussels sprouts, broccoli, cauliflower, cabbage, daikon radish, collard greens, garlic, kale, horseradish, onion, leek, radish, peas, scallion, swiss chard, Sauerkaut, spinach, split peas, turnip, soybeans, and watercress.
• Fruits to avoid: Dried fruits, dried coconut, grapes, papaya, and pineapple.
• Dairy and dairy alternatives to avoid: Cow, sheep, and goat milk, all cheese, cottage cheese, yogurt, whey, eggs, coconut milk from a carton, and soy products.
• Animal protein to avoid: Red meat, fish, and poultry white meat.
• Legumes to avoid: All legumes, including beans, lentils, bean sprouts, and soy, etc.
• Herbs to avoid: Chives, curry, ginger, horseradish, and turmeric.
• Other things to avoid: Amaranth, buckwheat, lemon and lime juice, frozen potatoes and french fries, peanuts, quinoa, tamarind, vinegar, wine, and wheat germ.
• Supplements to avoid: ALA, bromelain and papain, chlorella, NAC, MSM, milk thistle, turmeric, DMSO, dairy source acidophilus, and cysteine.

What Can You Eat on A Low Sulfur Diet?

Vegetables that are good to eat include.

• avocado
• carrots
• celery
• tomato
• sweet potato
• beets
• chard
• spinach
• cucumber
• bamboo shoots
• alfalfa sprouts
• squash
• pumpkin
• eggplant,
• green peppers (capsicum)
• For spice, consider ginger and chili peppers.

TIP: If you absolutely cant give up animal protein you can try some fish and poultry a 1-2 times a week and monitor any reactions. Keep in mind this is not a long term diet restriction.

Nuts, Seeds, Beans, Lentils, Grains to Avoid if You Have Hydrogen Sulfide SIBO

• Brazil nuts
• Almonds are moderately high
• Sesame seeds
• Peanuts
• Soybeans

Supplements To Avoid If You Have Hydrogen Sulfide SIBO

Supplements, ingredients and additives you will want to avoid or limit

• Alpha lipoic acid
• Glucosamine sulfate
• Glutathione
• Chondroiton sulfate
• Methylsulfonylmethane (MSM)
• Carageenan (often added to dairy products; read labels)
• Many other ingredients that mention sulfur, sulfite, or sulfate

Testing for Excess Hydrogen Sulfide Overproduction

I’ve discussed how traditional SIBO breath tests don’t account for hydrogen sulfide gas, which makes it extremely hard to detect and diagnose hydrogen sulfide overproduction in the gut. With that said, a flat-line breath test could suggest it — it just won’t confirm it.

When you work with a functional medicine doctor, they’ll likely perform a breath test to rule out hydrogen or methane-based SIBO. If a flat-line is received, they’ll start to look over your symptoms and will largely be on the lookout for frequent flatulence that smells like rotten eggs.

They’ll also have several other, more complex gastrointestinal tests that will look for overgrowth bacteria in the gut. If they believe your symptoms could be caused by hydrogen sulfide SIBO, then they’ll have you follow the low-sulfur diet to see if the symptoms worsen or get better.

Dr. Hagmeyer Is Here to Help!

If you want to learn more about the hidden SIBO that most doctors don’t account for or believe you’re suffering from hydrogen sulfide small intestinal bacterial growth, I can help. I specialize in functional medicine and would be honored to help you better understand your symptoms.

If you suspect that your symptoms may be related to SIBO or high sulfur levels in your body, schedule a brief phone consult today With more than 20 years of experience in helping patients from around the world, I can help you get back on track at Dr.Hagmeyer.com!