Podcast Summary:

What’s That Rash? — “Can functional mushrooms really help treat cancer?”
ABC News, February 11, 2025

Episode Overview

This episode dives into the science and health claims surrounding “functional mushrooms” – non-psychedelic varieties promoted for purported health benefits such as cancer treatment, immune system support, improved cognition, energy boosts, and even increased libido. Host Dr. Norman Swan (B) and co-host Tegan Taylor (C) explore the historical, cultural, and scientific context of mushrooms, critically examine popular claims, and discuss the current state of research.

Key Discussion Points & Insights

1. Mushrooms in History and Culture

• Historical Use:
  • Ancient humans, including Ötzi the Iceman from 5300 years ago, carried mushrooms for medicinal purposes.
  • Chinese texts (e.g., Shen Nong Ben Cao Jing) describe numerous medicinal uses for mushrooms.
  • Indigenous Australian uses include inhaling mushroom smoke for sore throats and using desert truffles for various topical applications.
    • [04:15–06:59]
• Dr. Swan’s Take:
  • “How medicine developed… and the idea that you could take substances to help yourself derived from the natural world.” (B, 05:29)
  • Both agree that traditional uses shouldn’t be wholly dismissed, given their place in the evolution of pharmacology.

2. What Are Functional Mushrooms?

• Definition & Clarification:
  • Not button mushrooms (common supermarket types), nor psychedelic mushrooms (e.g., psilocybin).
  • Refers to varieties like turkey tail, cordyceps, lion’s mane, touted for unique, non-psychoactive health effects.
    • [03:29–04:15]
  • Paul Stamets, a noted mycologist, frequently referenced in popular and scientific literature.

3. The Evidence (or Lack Thereof)

• Review of Scientific Studies:
  • “The evidence is not great. Unfortunately at the moment, it’s poor studies published in second-rate journals… not all, but some.” (B, 08:19)
  • Beta glucans and other bioactive compounds in mushrooms may influence the immune system and inflammation.
  • Most data derives from test-tube or animal studies; evidence from well-controlled human clinical trials is sparse.
    • [08:19–09:03]
• Anti-Cancer Claims:
  • Research focuses on mushrooms as adjuncts to cancer therapy, not as standalone treatments.
  • Some mushrooms may reduce chemo toxicity, allowing higher doses or more consistent dosing.
    • “If some of these mushrooms reduce the toxicity of these cancer drugs… that’s really good for you because it means that the cancer drug’s more effective.” (B, 09:11)
  • No evidence for mushrooms curing cancer on their own.
• Cognitive & Neurological Claims:
  • Promising early research, e.g., lion’s mane extract in preclinical animal studies induced nerve growth—potential applications for dementia (referencing a recent Queensland Brain Institute study).
    • “They've synthesized a compound from lion’s mane mushrooms and… found that… it induces nerve growth and could be a way of treating… dementia.” (B, 10:39)
• Immune, Energy, Stress, and Libido Claims:
  • Most such claims likely piggyback on general feelings of well-being and could be placebo-driven.
  • “Those are attributes… with a very high placebo effect… they’re psychological, they’re about a sense of wellbeing.” (B, 11:54/12:03)

4. Are Functional Mushrooms Special?

• Nutrition Context:
  • All edible mushrooms are healthy—fiber, polysaccharides, nutrients, and potentially beneficial for the microbiome.
  • No strong evidence that “functional” types are vastly superior to ordinary mushrooms in most respects.
    • [12:56–13:41]

5. How Does Form/Processing Matter?

• Delivery Format:
  • Powders, extracts, raw/cooked forms all vary; processing likely changes efficacy and risk profile.
  • Issues with quality control, concentration standards, and contamination risk in supplements.
    • “Does it have contaminants in it? There are all sorts of risks, but also benefits of the powder in that you’re taking it in a concentration.” (B, 14:25)
  • Extracts may act more like a drug—potential for side effects higher than with whole mushrooms.
    • [13:41–15:01]
• Cooking/Heating:
  • Heating and processing likely alter active constituents, but more research is needed.

6. Summary Opinions and Practical Takeaways

• Evidence Review:
  • Some interesting signals, but a lack of robust, high-quality clinical research.
  • “We’re not finding a big signal of harm here and we are finding interesting signals of benefit.” (B, 15:22)
  • Greatest promise lies in mushroom-derived compounds developed into standardized pharmaceuticals in future.
• Safety and Recommendations:
  • Don’t self-treat cancer with mushrooms, but eating edible varieties as part of a healthy diet seems safe.
  • Caution against foraging unless you’re an expert—risk of poisonous lookalikes.
  • “Probably safer buying the whole mushroom… rather than necessarily a powder and you’ve got no idea what’s in it.” (B, 16:10)
• Placebo and Lifestyle:
  • Improved diet overall—from including more mushrooms or functional foods—may be responsible for reported health improvements.

Notable Quotes & Memorable Moments

• On Historical Context:
  • “I can’t have it both ways. If I’m going to tell you… whole foods… are good for you… bioactive compounds… reduce inflammation… then say ‘it’s all bullshit about mushrooms’ – because we are saying that the natural world has a lot to offer us.” (B, 07:11)
• On Evidence Quality:
  • “The evidence is not great… it’s poor studies published in second-rate journals, to be cruel about it.” (B, 08:19)
• On Mushrooms for Cancer:
  • “I just want to re-emphasize… cancer research in mushrooms has been using… alongside cancer therapy to make cancer therapy better… not as the sole treatment.” (B, 15:32)
• On Supplements and Safety:
  • “Safer buying the whole mushroom… rather than necessarily a powder and you’ve got no idea what’s in it and that the whole mushroom itself is unlikely to do you any harm and may well do you some good.” (B, 16:10)
• On Placebo Effects:
  • “Those are attributes of a compound which have a very high placebo effect… psychological… a sense of wellbeing.” (B, 11:54)

Timestamps for Key Segments

• [03:29] — Defining functional mushrooms and main questions from listeners
• [04:15–06:59] — Historical uses and context; medicinal mushrooms in ancient texts and oral histories
• [08:19] — Critical look at the current evidence base; explanation of active compounds
• [09:11] — How mushrooms might help with cancer treatment (adjunct, not replacement)
• [10:39] — Lion’s mane research and cognition claims
• [11:54–12:56] — The limitations and unreliability of claims around stress, energy, libido
• [13:41–15:01] — How mushroom form (powder, cooked, extract) may affect efficacy and safety
• [15:17–16:28] — Practical advice: Proceed with caution, stick to whole mushrooms, beware foraging

Conclusion

The hosts stress an evidence-based, skeptical but open-minded approach to functional mushrooms. There’s historical precedent for their use, some promising early-stage science, and generally little harm shown—but robust clinical benefits have not been conclusively demonstrated. Edible mushrooms can be enjoyed as part of a healthy diet, but consumers should be cautious about supplements and unverified health claims, especially concerning serious conditions like cancer.