Low Sulfur Diet for H2S SIBO & Sulfur Intolerance: Foods to Avoid and How to Reintroduce Them.

Article
Written By Tamara Agusta

By Tamara Agusta, MSc, DipION, NgC, mBANT. Published September 29, 2026.

Illustration of a garlic bulb and cloves, a halved red onion, broccoli and curly kale, with golden wisps rising from them to represent sulfur
AI-generated illustration of garlic, red onion, broccoli and kale, some of the most common high sulfur foods.
Table of Contents
  1. What is a low sulfur diet?
  2. Why your body needs sulfur
  3. Sulfur, sulfates, sulfites and thiols
  4. What is sulfur intolerance?
  5. H2S SIBO and the low sulfur diet
  6. Symptoms
  7. What causes it?
  8. How to follow a low sulfur diet
  9. Supportive strategies
  10. Case study from my practice
  11. FAQ

If garlic makes you bloat, wine leaves you flushed, and "healthy" foods like broccoli and kale seem to make things worse, you've probably wondered whether sulfur is the problem, or whether you might have hydrogen sulfide (H2S) SIBO. In clinic, I've seen sulfur sensitivity hide behind symptoms as varied as itchy skin, night sweats and headaches. In this guide I'll explain what sulfur intolerance is, how it connects to H2S SIBO, what the evidence does and doesn't say, and how to run a low sulfur trial properly, including the reintroduction step most people skip.

What is a low sulfur diet?

A low sulfur diet is a short-term elimination diet, usually two weeks, that reduces foods high in sulfur compounds: garlic, onions, cruciferous vegetables, eggs, dairy, most meats, legumes and sulfite-preserved foods. It's followed by a structured reintroduction to find out which foods you personally react to. It's often used for sulfur sensitivity and H2S SIBO, and it's a tool for answering a question, not a way to eat forever.

Why your body needs sulfur

Sulfur isn't the enemy. It's an essential element, and your body uses it constantly.1

  • Detoxification. Your liver attaches sulfate to many hormones, medications and toxins so they can be excreted in urine. This process is called sulfation.
  • Antioxidant defense. Glutathione, often called the body's master antioxidant, depends on a sulfur-containing amino acid (cysteine) to neutralize free radicals.
  • Structure. Sulfated molecules help build cartilage, tendons and ligaments, and line your blood vessels and mucous membranes.
  • Protein. Two amino acids, methionine and cysteine, contain sulfur. They're found throughout the body's proteins, including albumin, which carries vitamins, minerals and hormones in the blood.

Very little of the sulfur we eat arrives as ready-to-use sulfate. Most comes from protein and plant compounds, and the body has to convert it. That conversion step is where things can go wrong.

Sulfur, sulfates, sulfites and thiols: what's the difference?

These words get used interchangeably online, which causes a lot of confusion. Here's how they differ:

TermWhat it isWhere you meet itWhy it matters here
SulfurThe element itselfProtein, garlic, onions, crucifers, eggsThe raw material your body has to process
SulfateThe stable, usable formMade in the body; also in Epsom saltThe form your body actually needs
SulfiteA reactive in-between formWine, dried fruit, some frozen potatoes, also made in the body and by gut bacteriaConverted to sulfate by the enzyme sulfite oxidase; can trigger reactions in sensitive people2
Hydrogen sulfide (H2S)A gas with a rotten-egg smellProduced by certain gut bacteriaUseful in tiny amounts; irritating to the gut lining in excess3
ThiolsCompounds containing a sulfur-hydrogen groupCysteine, glutathione, NAC; many sulfur-rich foods and supplementsSome people report reacting to thiols specifically ("thiol sensitivity")

One more thing sulfur intolerance is not: an allergy to "sulfa" antibiotics. Sulfonamide drug allergies are a separate issue and don't mean you react to sulfur in food.

What is sulfur intolerance?

Sulfur intolerance, also called sulfur sensitivity, describes a pattern where someone reacts to sulfur-rich foods even though sulfur itself is essential. It isn't a formally recognized medical diagnosis, and there's no single validated test for it. It's a clinical framework, and the most practical way to explore it is a time-limited elimination and reintroduction.

The framework I've used in practice comes from Dr. Greg Nigh and Maria Zilka.1,4 It goes like this: when the normal conversion of sulfur into sulfate gets "clogged," the body looks for a workaround. That workaround is an overgrowth of sulfate-reducing bacteria (SRB) and other H2S-producing bacteria, either in the large intestine (large intestinal bacterial overgrowth, or LIBO) or in the small intestine (small intestinal bacterial overgrowth, or SIBO). These bacteria turn dietary sulfur into sulfite and H2S, a gas that tissues can eventually convert into sulfate. The body gets its sulfate, but the byproducts of the detour cause symptoms.

Sulfur in foodProtein, garlic, onions, crucifers, wine
The body takes a detourA workaround to get the sulfate it needs
CloggedThe direct route to sulfate is blockedLow cofactors (molybdenum, B6, B12), genetics (e.g. CBS, SUOX), heavy metals and toxins, oxalates
SRB overgrowIn the colon (LIBO) or the small intestine (SIBO)
H2S and sulfite build upByproducts of the detour
SulfateThe detour still delivers it
Detox & repairSulfation, glutathione, connective tissue
SymptomsThe body reacts to the byproducts: gut, skin, head, sleep
The "workaround" model of sulfur intolerance. When dietary sulfur can't be converted to sulfate directly, gut bacteria take a detour that still produces sulfate, but its byproducts, H2S and sulfite, drive symptoms. Adapted from the model in Nigh & Zilka's Low Sulfur Protocol.

How much of this is proven? The research on H2S in the gut is real. A 2021 meta-analysis found that SRB are the main producers of H2S in the gut, that high concentrations are involved in gut inflammation, and that SRB occurrence was associated with inflammatory bowel disease.3 The same review notes that excess H2S interferes with how colon cells use butyrate, their main fuel. It also points out that SRB are found in a large share of healthy people too, somewhere between 12% and 79% depending on the study. So having these bacteria isn't the problem; balance is.

Human studies in ulcerative colitis add some support. In a 2004 study that followed 191 people in remission for a year, higher intakes of meat, protein and alcohol, and of sulfur and sulfate overall, were associated with relapse.5 But the first randomized, placebo-controlled trial of a sulfide-reducing diet, presented in 2026, found that although the diet lowered H2S in stool, it didn't improve ulcerative colitis any more than a sham diet did.6 That's a different condition from sulfur intolerance, and so far only a conference abstract, but it's a useful reminder that lowering H2S may not be enough on its own.

The "workaround" explanation itself is a clinical model. It fits what many practitioners observe, but it hasn't been tested in controlled trials. I think it's worth being honest about that.

H2S SIBO and the low sulfur diet

SIBO, small intestinal bacterial overgrowth, means there are too many bacteria in the small intestine, causing digestive symptoms.7 Most of the gut's bacteria normally live in the colon, and that's where SRB usually do their work. In SIBO, bacteria overgrow further up, in the small intestine, where food is still being digested and absorbed. When the overgrowth is in the colon instead, practitioners often call it LIBO, large intestinal bacterial overgrowth.8 LIBO isn't yet a formally defined condition in gastroenterology guidelines, but it's a useful way to describe where the problem sits.

SIBO is usually described by the gas the bacteria produce, measured on a breath test:

  • Hydrogen: the classic form of SIBO.
  • Methane: now called intestinal methanogen overgrowth (IMO), because the microbes involved aren't technically bacteria and aren't confined to the small intestine. It's linked to constipation.7
  • Hydrogen sulfide (H2S SIBO): the newest and least understood type. Research has linked breath H2S to diarrhea,9 although not all studies agree,10 and a newer three-gas breath test now measures it directly. A 2025 study by the Cedars-Sinai team that developed that test found that breath H2S and methane correlate with the gas-producing microbes sampled directly from the small intestine.11 Researchers and testing labs now often call this intestinal sulfide overproduction (ISO), and a 2026 study found it had a distinct effect on the small intestine's lining, changing the activity of genes linked to H2S toxicity, energy production and antioxidant defense.12

This matters for your diet. Most SIBO diets, such as low FODMAP, reduce fermentable carbohydrates, which feed hydrogen- and methane-producing microbes. H2S producers generate their gas from sulfate and sulfur-containing amino acids instead, so an H2S SIBO diet reduces sulfur foods.8 Garlic and onions are on both lists, but much of the rest differs. If you've tried a standard SIBO diet without much relief, H2S may be part of the story.

Not every practitioner agrees the diet is needed, though. Dr. Ruscio points out that no studies have shown a low sulfur diet helps H2S SIBO specifically, and suggests starting with broader gut support and a low FODMAP diet, keeping low sulfur for symptoms that persist.10 It's a fair point, and it's one reason this guide treats the diet as a short test rather than a treatment.

In Dr. Nigh's view, H2S SIBO can itself be part of the workaround described above: an overgrowth that exists because the body needs sulfate.4 That's also why reducing sulfur can calm symptoms without resolving the cause. Symptoms of SIBO overlap with many other conditions, so it's worth testing with a practitioner rather than self-diagnosing.

Symptoms of sulfur intolerance

Because sulfur is involved in so many systems, symptoms can show up almost anywhere. These are the ones most commonly reported in clinical practice:1

  • Bloating and gas that's hard to pass
  • Diarrhea or constipation
  • Reflux
  • Brain fog and headaches
  • Fatigue
  • Skin rashes, hives, itching or acne
  • Flushing, hot flashes or night sweats
  • Strong body odor
  • Reactions to garlic, onions or wine
  • Joint stiffness
  • Anxiety
  • Rapid heart rate

Sulfite reactions are a related but distinct issue. Sulfite additives can cause skin, gut and breathing reactions in sensitive people, and most studies put sulfite sensitivity at 3 to 10% of people with asthma.2

When to see a doctor first

Many of these symptoms overlap with conditions that need proper medical assessment. Please see your doctor before experimenting with your diet if you have blood in your stool, unexplained weight loss, pale or unusually colored stools, persistent diarrhea, difficulty swallowing, or wheezing or swelling after eating. Sulfite reactions in people with asthma can be severe and need medical management, not a food list.2

What causes sulfur intolerance?

Sulfur intolerance is rarely about sulfur itself. It's usually about the body's ability to keep sulfur in balance. These are the factors I look at:

Gut dysbiosis and H2S overgrowth

An overgrowth of SRB and other H2S producers, in the colon or in the small intestine as H2S SIBO, is the most direct link. It's also the part of the picture that can now be tested, with a three-gas breath test for H2S SIBO or a comprehensive stool test for wider dysbiosis.

Missing cofactors

Converting sulfite into sulfate depends on an enzyme called sulfite oxidase, which needs molybdenum to work.13 Vitamins B6, B12 and folate support the wider sulfur and methylation pathways. True molybdenum deficiency is rare: according to the NIH, it has essentially only been reported in a rare genetic disorder, and most people get enough from food.13 So supplementing molybdenum for sulfur sensitivity is based on clinical experience rather than trials.

Genetics

Genes such as CBS, SUOX and MTHFR sit on the sulfur and methylation pathways, and practitioners often look at them in sulfur-sensitive clients. To be clear about the evidence: severe SUOX and molybdenum cofactor defects are rare, serious conditions diagnosed in infancy.14 They're only a few of the many enzymes involved in processing sulfur, and several depend on nutrient cofactors: CBS and CTH, for example, need vitamin B6, while SUOX needs molybdenum. That link to nutrition is what makes them interesting to a Nutrigenetic Counsellor like me. Research linking common variants of these genes to food-level sulfur sensitivity is still limited, though. Genetics can add context, but it isn't a diagnosis.

Methylation and overlap with histamine

Methylation helps regulate sulfur metabolism, and it also affects histamine breakdown, because one of the histamine-clearing enzymes needs SAMe, and SAMe is synthesized directly from the sulfur-containing amino acid methionine. That's one reason sulfur and histamine issues often show up together. Sulfites are also histamine liberators. If you recognize yourself in both, my guide to histamine intolerance covers the other half of the picture, and my Low Histamine Food List works alongside this one.

Oxalates

Sulfate and oxalate share some of the same transport machinery. SLC26A6, an anion exchanger in the gut and kidneys, can move both, and it's one of the main ways the gut secretes oxalate back out. In mice without it, oxalate absorption rises enough to cause kidney stones.15 Whether this interplay matters for sulfur-sensitive people hasn't been studied directly in humans. Clinically, though, sulfur and oxalate issues often show up together.

Toxic load

Heavy metals and other toxins that bind sulfur are part of the clinical model too. Some researchers have proposed that the herbicide glyphosate disrupts sulfate supply and beneficial gut bacteria by chelating essential nutrients needed to convert sulfite to sulfate, like molybdenum.16 That remains a hypothesis rather than an established cause, so I mention it for completeness, not as a reason to panic.

How to follow a low sulfur diet

The most reliable way to find out whether sulfur is involved is a time-limited trial. If your symptoms improve noticeably during the elimination phase, sulfur is likely part of the picture. If nothing changes, it probably isn't, and you can go back to your usual diet.

Step 1: Reduce high sulfur foods (about 2 weeks)

Protocols vary in length. Dr. Nigh's protocol uses two weeks, Dr. Ruscio's dietary trial uses 5 to 7 days, and The SIBO Doctor's H2S diet suggests 4 to 6 weeks.1,17,8 I usually work with two weeks: long enough for most people to notice a difference, short enough to stay nutritionally safe.

High sulfur foods most protocols agree on avoiding:

  • Alliums: garlic, onions, leeks, shallots, scallions, chives
  • Cruciferous vegetables: broccoli, cauliflower, cabbage, kale, Brussels sprouts, bok choy, arugula, radish
  • Eggs, both whites and yolks
  • Dairy, except butter and ghee
  • Most meat, especially red meat and processed meat
  • Legumes and soy, including tofu and tempeh
  • Sulfite sources: wine, beer, sulfured dried fruit, and some frozen potato products
  • Sulfur-containing supplements such as MSM, NAC, glutathione and alpha-lipoic acid (only stop prescribed supplements with your practitioner's agreement)

Low sulfur foods that are generally well tolerated include most fresh fruit, carrots, squash, sweet potato, beets, cucumber, zucchini, lettuce, bell peppers, white rice, olive oil, butter and ghee. For the complete YES and NO list by food group, see my Low Sulfur Food List.

A note on the gray areas. There's genuinely contradictory information about some foods. For example, The SIBO Doctor's list allows spinach and legumes that other protocols exclude.8 Protein is another difference: Dr. Nigh's protocol is vegetarian, while Dr. Ruscio's allows limited fatty fish and dark-meat poultry.1,17 A low sulfur diet can easily end up low in protein, so plan your meals rather than just removing foods.

Coconut is another source of confusion. Coconut itself isn't especially high in sulfur, and Dr. Ruscio's list notes coconut oil is low in sulfur but can be reactive for some people. Dried coconut and some boxed coconut milks, on the other hand, are often preserved with sulfites, which is why they appear on avoid lists.17,1 If you use coconut products, check the label for sulfites. Unsweetened coconut water with no additives is fine.

Organic doesn't automatically mean sulfur-free, either. Elemental sulfur is one of the oldest crop fungicides and is permitted in organic farming,18 which is one reason grapes appear on avoid lists. Rinsing produce well is sensible whether it's organic or not.

A few other foods readers often ask me about: fresh celeriac is fine (not pickled or canned), while I suggest avoiding spirulina, which like chlorella is a concentrated source of sulfur-containing amino acids, and chestnuts, which aren't as high in sulfur as garlic or onions but are best left out until you've finished the elimination phase.

Take the guesswork out of it

This article covers the main food groups, but the details are where most people slip up: which herbs and spices, drinks, sweeteners, grains and supplements are safe. My Printable Low Sulfur Diet & Food List sorts every YES and NO food across 12 categories on one page, including those gray areas, so it doubles as your grocery list. A second page covers the elimination and reintroduction phases. Stick it on your fridge or keep it on your phone.

Get the Low Sulfur Food List

Practitioner? You're welcome to print it as a handout for your clients.

Step 2: Expect a possible "sulfur dump"

Some people feel worse before they feel better. Dr. Nigh describes a temporary flare, often skin eruptions, brain fog, poor sleep or night sweats, in the first 2 to 4 days, and estimates it affects about 30% of the people on his protocol.1 This is a clinical observation rather than a studied phenomenon. If symptoms are severe or don't settle within a few days, stop and check in with a practitioner.

Step 3: Reintroduce foods one at a time

This is the step that actually gives you answers, and it's the one most people rush. The goal is to test each food in isolation so a reaction is clearly linked to one thing. The best order depends on you: start with the foods you eat most, miss most or most suspect. As an example, this is an order I've used with clients, inspired by Dr. Nigh's protocol:1

  1. Garlic
  2. Onion
  3. Cabbage
  4. Broccoli
  5. Eggs
  6. Kale
  7. Coffee
  8. Wine (optional)
  9. Beer (optional)

How to test each food: have a normal portion at breakfast. If you have no symptoms, have it again at lunch, then stop eating it. Wait a full day before testing the next food. If you do react, don't eat it again that day, and wait until your symptoms have completely settled before testing the next food, even if that takes longer than two days. Keep every tested food out of your diet until you've finished the whole list. After that, bring back the rest of your usual foods and continue to avoid the ones you reacted to.

Tracking matters here. Memory is unreliable when you're testing nine foods over several weeks, so write down what you ate, when, and any symptoms over the following 24 to 48 hours. A simple symptom and food tracker makes patterns much easier to spot. If your symptoms include diarrhea, constipation or changes in your stools, which is common with H2S SIBO, the version with a stool tracker lets you log them on the Bristol Stool Scale too.

Step 4: Don't stay low sulfur long-term

Your body needs a steady supply of sulfate, including for a healthy gut lining, so restricting sulfur relieves symptoms without fixing the underlying problem. Reacting to a food during reintroduction doesn't mean avoiding it forever. Many people can gradually bring reactive foods back within a few months as the underlying issues are addressed.1 Staying restrictive has costs. Cruciferous vegetables and legumes are some of the most protective foods we have. In a large US cohort, the dietary pattern most linked to sulfur-metabolizing gut bacteria was high in processed meat and low in vegetables and legumes, and it was associated with a higher risk of early-onset colorectal adenomas, which are precursors of colorectal cancer.19 So the long-term goal is a diverse diet you tolerate well, not a permanent low sulfur one.

Supportive strategies

Diet reduces the sulfur load, but on its own it tends to give short-term relief. The underlying imbalance is what needs attention.1 These are strategies commonly used alongside a low sulfur trial. They're general information, not a personal protocol, so please discuss supplements with a qualified practitioner, especially if you take medication.

  • Molybdenum: the cofactor for sulfite oxidase, the enzyme that turns sulfite into sulfate.13
  • B vitamins: B6, B12 and folate support the sulfur and methylation pathways. The hydroxocobalamin form of B12 binds H2S in laboratory studies,20 which is why some practitioners prefer it.
  • Gut support: addressing the dysbiosis itself, for example with appropriate diet, probiotics and butyrate support. This is best guided by testing and a practitioner.
  • Binders: some practitioners use binders such as activated charcoal or bismuth, which bind H2S in the gut.1 A 1998 study found that bismuth subsalicylate markedly reduced H2S release in the human colon.21 Binders can also bind medications and nutrients, and bismuth subsalicylate contains a salicylate (a relative of aspirin), so they're for short-term use with a practitioner's guidance only.
  • Sweating: if heavy metals or other toxins are part of what's clogging sulfur metabolism, sweating is worth considering. A 2012 systematic review found that arsenic, cadmium, lead and mercury are excreted in sweat, often at higher concentrations than in blood or urine in people with higher exposure, although the authors called for proper trials.22 Saunas, exercise and hot baths all count. Stay well hydrated, and check with your doctor first if you have a heart condition, low blood pressure or are pregnant.
  • Epsom salt baths or foot baths: Epsom salt is magnesium sulfate, and soaking in it is a popular way to top up sulfate without it passing through the gut. I'm not aware of any peer-reviewed research showing that Epsom salt baths raise sulfate levels. That doesn't mean they don't; it means the question hasn't been properly studied. The study usually cited is a small 2010 report on 19 volunteers, published by the Epsom Salt Council rather than in a peer-reviewed journal, which found blood sulfate and magnesium rose after bathing.23 A 2017 review found the evidence for magnesium absorption through the skin lacking.24 I still recommend them: they're generally well tolerated, they're relaxing, and a hot bath gets you sweating too.
  • Read labels: garlic powder, onion powder and sulfite preservatives hide in stock cubes, sauces, dressings and even some medications.

Case study: when a low sulfur diet helped, and why it wasn't the end of the story

This case is shared with my client's consent, and identifying details have been removed.

The picture. She came to me with fatigue from various allergies, bloating that was hard to relieve, itchy skin, eyes and ears, heavy night sweats with a strong body odor, frequent headaches, and known reactions to onions, garlic and wine. Her diet was mostly vegetarian and, without her realizing it, built around high sulfur foods: broccoli, cauliflower, green beans, chickpeas and buckwheat most days. Her protein intake was very low.

What we did. Based on her symptom pattern, I suspected sulfur intolerance and H2S SIBO. We started a two-week low sulfur protocol with molybdenum, a probiotic and a B-vitamin complex (which she didn't take the first time around), and increased her protein with low sulfur options such as oily fish and dark-meat poultry.

What happened. Within ten days, her stomach felt flat, with only mild gas that was easy to pass. Her sweating and itching reduced and her skin cleared. We tracked her main concerns by rating them on a scale of 0 (as good as it can be) to 6 (as bad as it can be):

Bloating6 → 2
Low energy3 → 2
Wellbeing3 → 1

The twist. Feeling so much better, she reintroduced foods on her own, several at once, and many symptoms came back. Brussels sprouts made her itchy, onions caused immediate bloating, and wine left her feeling unwell. Because she'd tested several foods together, it was hard to know exactly what was doing what. We repeated the protocol with the structured, one-food-at-a-time reintroduction described above.

What I learned. Her improvement strongly suggested sulfur was part of the picture, though with several changes at once it wasn't proof on its own. It also wasn't the whole answer. Over three further sessions, the work uncovered other layers, including broader gut imbalances, which is to be expected. A low sulfur diet may be the first thread you pull, but it's rarely the final fix.

Frequently asked questions

How long should I follow a low sulfur diet?

Usually about two weeks before reintroduction, although protocols range from 5 days to 6 weeks. It's designed as a short-term test, not a permanent diet, because many high sulfur foods, like cruciferous vegetables and legumes, are important for long-term health.

Is a low sulfur diet the same as an H2S SIBO diet?

Essentially, yes. "H2S diet" and "low sulfur diet" describe the same approach: reducing the sulfur-rich foods that H2S-producing bacteria use. The differences are in the details of individual protocols rather than the principle. For example, The SIBO Doctor's version allows legumes and spinach, which other protocols exclude. On its own, the diet calms symptoms rather than addressing why the overgrowth happened.

How do I get enough protein on a low sulfur diet?

It's one of the hardest parts, because eggs, dairy, most meat and legumes are all high in sulfur. Some protocols go vegetarian for the elimination phase, but my clients have generally done best with a small amount of lower sulfur animal protein: about 4 oz (114 g) per meal and no more than 8 oz (228 g) a day, the same limits Dr. Ruscio's protocol uses,17 from fatty fish (anchovies, herring, mackerel, salmon, sardines), clams, oysters or dark-meat poultry. Rice protein powder can help fill the gap.

Can I eat canned fish on a low sulfur diet?

Yes, canned fatty fish such as sardines, mackerel or salmon is fine, as long as it's packed in water or olive oil with nothing else added: no flavorings, sauces or preservatives, which can contain sulfites, garlic or onion.

How much rice can I eat on a low sulfur diet?

About ½ cup per meal, measured cooked, and the same goes for polenta. White rice tends to be the best tolerated grain, and some protocols remove other grains entirely during the trial.17

Is there a test for sulfur intolerance?

There's no single validated test. A three-gas breath test can detect excess H2S, and stool testing can show signs of dysbiosis, but the most practical way to find out whether sulfur-rich foods affect you is a structured elimination and reintroduction.

Is sulfur intolerance the same as a sulfite allergy?

Not quite, for two reasons. First, most reactions to sulfites are a sensitivity (an intolerance) rather than a true allergy, meaning they don't involve the IgE antibodies behind classic food allergies, although they can still be severe, especially in people with asthma. Second, sulfites are only one group of sulfur compounds. Sulfur intolerance, as described here, is a broader difficulty handling sulfur from many foods, of which sulfites are one part. Anyone who wheezes or swells after eating should see a doctor.

If I'm allergic to sulfa drugs, should I avoid sulfur foods?

No. Sulfa (sulfonamide) drug allergies are unrelated to sulfur in food, so a sulfa allergy on its own isn't a reason to follow a low sulfur diet.

Why do I react to garlic and onions but not other sulfur foods?

That's very common. Most people react strongly to one or two foods rather than to every source of sulfur, which is exactly why the reintroduction phase is so useful. Garlic and onions are also high in FODMAPs, which can cause bloating for a completely different reason.

Can I have Epsom salt baths on a low sulfur diet?

Yes, and I still recommend them. I'm not aware of peer-reviewed research showing they raise sulfate levels, which doesn't mean they don't; it just hasn't been properly studied. A hot bath also gets you sweating, and sweating, whether from a bath, sauna or exercise, is one route the body uses to excrete heavy metals and other toxins that may be part of the problem. Stop if you notice a skin reaction.

The bottom line

Sulfur is essential, and most people handle it well. But if your symptoms seem to follow garlic, onions, crucifers or wine, or you suspect H2S SIBO, a short, structured low sulfur trial can tell you a lot. The key is treating it as an experiment: reduce for about two weeks, reintroduce one food at a time, track what happens, and then look at why your body struggled in the first place. The Printable Low Sulfur Diet & Food List gives you everything you need to run the trial yourself.

References (24)
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  19. 19Cohort studyNguyen LH, et al. The sulfur microbial diet is associated with increased risk of early-onset colorectal cancer precursors. Gastroenterology. 2021;161(5):1423-1432. Source ↗
  20. 20Animal studyGallego-Martin T, et al. Hydroxycobalamin reveals the involvement of hydrogen sulfide in the hypoxic responses of rat carotid body chemoreceptor cells. Antioxidants. 2019;8(3):62. Source ↗
  21. 21Human studySuarez FL, Furne JK, Springfield J, Levitt MD. Bismuth subsalicylate markedly decreases hydrogen sulfide release in the human colon. Gastroenterology. 1998;114(5):923-929. Source ↗
  22. 22Systematic reviewSears ME, Kerr KJ, Bray RI. Arsenic, cadmium, lead, and mercury in sweat: a systematic review. J Environ Public Health. 2012;2012:184745. Source ↗
  23. 23Industry reportWaring RH. Report on absorption of magnesium sulfate (Epsom salts) across the skin. University of Birmingham; published by the Epsom Salt Council. Source ↗
  24. 24ReviewGröber U, Werner T, Vormann J, Kisters K. Myth or reality: transdermal magnesium? Nutrients. 2017;9(8):813. Source ↗

This article is for educational purposes only and isn't a substitute for personalized medical advice. Please talk to your doctor or a qualified practitioner before making significant changes to your diet or supplements. See my full medical disclaimer.

Tamara Agusta https://eyzhn.co
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