Brewer's yeast is one of the most studied dietary factors in HS. Unlike many dietary claims in the HS community that are based purely on anecdote, the brewer's yeast connection has a plausible biological mechanism and some supporting clinical evidence. This guide explains what brewer's yeast is, where it is found, and how to do a proper elimination trial.
What Is Brewer's Yeast and Why Might It Affect HS?
Brewer's yeast (Saccharomyces cerevisiae) is a fungus used in the fermentation of beer, wine, and some breads. It is also sold as a nutritional supplement. The proposed mechanism for its effect on HS involves beta-glucans and mannoproteins in the yeast cell wall, which can activate the NLRP3 inflammasome and stimulate pro-inflammatory cytokine production, including TNF-alpha and IL-1beta, the same pathways targeted by biologic therapies for HS.
A 2013 Italian study by Cannistra and colleagues found that a yeast-exclusion diet led to significant improvement in HS activity in a small cohort of patients. A larger French observational study published in 2021 found that 30% of HS patients who eliminated brewer's yeast reported a reduction in flare frequency. While these are not large randomized trials, the consistency of the finding across multiple studies and the plausible mechanism make brewer's yeast elimination one of the better-supported dietary interventions for HS.
Foods That Contain Brewer's Yeast
The following foods contain brewer's yeast or active Saccharomyces cerevisiae and should be avoided during an elimination trial: all types of beer (including non-alcoholic beer), wine and champagne, most commercially baked breads and rolls made with active dry yeast or instant yeast, pizza dough made with active yeast, nutritional yeast (sold as a cheese substitute), Marmite and Vegemite, yeast extract spreads, and some fermented condiments.
Foods that do NOT contain brewer's yeast and are generally safe: sourdough bread (uses wild lactobacillus fermentation, not Saccharomyces cerevisiae), unleavened breads such as tortillas, flatbreads, and crackers, rice, pasta, potatoes, all fruits and vegetables, meat, fish, eggs, and most dairy products.
How to Do a Proper Elimination Trial
A proper elimination trial requires strict avoidance for a minimum of 12 weeks, as HS flare cycles can be long and a shorter trial may not capture meaningful change. During the elimination period, keep a symptom diary recording the number of new lesions, pain scores, and drainage. At the end of 12 weeks, compare your symptom diary to the 12 weeks before the trial.
If you see improvement, you can try a controlled reintroduction of one brewer's yeast-containing food at a time to confirm the connection. If you see no change after 12 weeks of strict elimination, brewer's yeast is likely not a significant trigger for you, and you can reintroduce it without concern.
Realistic Expectations
Not everyone with HS will respond to brewer's yeast elimination. Studies suggest that roughly 30-50% of patients who try it see some benefit. It is more likely to be helpful in patients with milder disease (Hurley Stage I or II) and less likely to produce dramatic results in severe Hurley Stage III disease, where systemic inflammation is driven by multiple pathways beyond dietary triggers. Brewer's yeast elimination is best viewed as one component of a comprehensive management plan, not a standalone treatment.