# Birch Polypore (Piptoporus betulinus)

**Canonical URL:** https://ingredients.hermeticasuperfoods.com/ingredients/birch-polypore
**Data Source:** Hermetica Superfoods Ingredient Encyclopedia
**Updated:** 2026-04-04
**Evidence Score:** 2 / 10
**Category:** Mushroom/Fungi
**Also Known As:** Piptoporus betulinus, razor strop fungus, birch bracket, birch conk, birch bracket fungus, razor strop, polypore fungus

## Overview

Birch polypore (Piptoporus betulinus) is a bracket fungus whose primary bioactives — beta-glucans and lanostane-type triterpenoids — modulate [immune function](/ingredients/condition/immune-support) via Dectin-1 receptor activation on macrophages and induce apoptosis in cancer cell lines. Most evidence remains preclinical, though its historical use as an antiparasitic agent dates back at least 5,300 years to the Iceman Ötzi.

## Health Benefits

• [Immune system](/ingredients/condition/immune-support) modulation through beta-glucan activation of Dectin-1 receptors on macrophages (preclinical evidence only)
• Potential anticancer effects via triterpenoid-induced apoptosis and p53 upregulation (limited to in vitro/animal studies)
• Traditional use for parasite expulsion, as carried by Ötzi the Iceman ~5300 years ago (historical evidence)
• Antimicrobial properties attributed to phenolic compounds (preclinical studies only)
• [Anti-inflammatory](/ingredients/condition/inflammation) effects through NF-κB downregulation and 5α-reductase inhibition (animal model evidence)

## Mechanism of Action

[Beta-glucan](/ingredients/condition/immune-support)s in birch polypore bind Dectin-1 pattern recognition receptors on macrophages and dendritic cells, triggering Syk kinase signaling and downstream NF-κB activation, which elevates [pro-inflammatory cytokine](/ingredients/condition/inflammation)s including TNF-α and IL-6. Lanostane-type triterpenoids — particularly piptamine and polyporenic acid C — promote apoptosis in tumor cell lines by upregulating p53 and activating caspase-3/-9 pathways while inhibiting Bcl-2 expression. Additionally, agaric acid derivatives present in the fruiting body may exert anthelmintic effects by disrupting [mitochondrial](/ingredients/condition/energy) ATP synthesis in parasitic organisms.

## Clinical Summary

No completed human clinical trials have evaluated birch polypore supplementation for any health outcome as of 2024. The anticancer and [immunomodulatory](/ingredients/condition/immune-support) data derive entirely from in vitro cell-line experiments (e.g., inhibition of HeLa and MCF-7 cell proliferation at IC50 values of 50–200 µg/mL) and rodent models, which frequently fail to translate to human efficacy. Antimicrobial activity against Staphylococcus aureus and Mycobacterium species has been demonstrated in laboratory assays, but therapeutic relevance is unknown. The overall evidence base is preliminary, and no dosage has been validated through controlled human research.

## Nutritional Profile

Macronutrients (per 100g dry weight, approximate): Protein 14–18g (containing all essential amino acids, though relatively low in methionine and cysteine; digestibility estimated at 60–70% due to chitin matrix interference); Carbohydrates 55–65g (predominantly structural polysaccharides); Dietary fiber 40–50g total (largely insoluble chitin 15–20g and beta-glucans 10–15g, particularly beta-1,3/1,6-glucans; soluble fiber fraction limited); Fat 2–4g (primarily linoleic acid and oleic acid, with minor ergosterol-derived sterols). Micronutrients: Potassium 1200–1800mg/100g dry weight (among the more concentrated minerals); Phosphorus 400–600mg/100g; Magnesium 80–120mg/100g; Iron 8–15mg/100g (non-heme, bioavailability reduced by polyphenol binding); Zinc 5–10mg/100g; Calcium 20–40mg/100g; Copper 1–3mg/100g. Vitamins: Ergosterol (provitamin D2) present at approximately 200–400mg/100g dry weight, convertible to vitamin D2 upon UV exposure (conversion efficiency varies with processing); B-vitamins including riboflavin (B2) ~2–4mg/100g and niacin (B3) ~15–25mg/100g; B12 absent (as with all fungi lacking bacterial symbiosis). Bioactive compounds: Triterpenoids (piptamine, polyporenic acids A/C, and betulinic acid derivatives) at approximately 1–3% dry weight — betulinic acid concentration estimated 0.1–0.5mg/g; Agaricic acid (a fatty acid derivative) reported with [antimicrobial](/ingredients/condition/immune-support) activity, concentration approximately 0.05–0.2% dry weight; Phenolic compounds including protocatechuic acid and caffeic acid derivatives, total polyphenols estimated 5–15mg GAE/g dry weight; Melanin-like pigments with [antioxidant](/ingredients/condition/antioxidant) capacity (DPPH radical scavenging IC50 reported ~0.8–1.5mg/mL in crude extracts). Bioavailability notes: Chitin cell walls significantly impair nutrient release — hot water extraction or prolonged cooking increases beta-glucan and mineral bioavailability by an estimated 30–50%; Betulinic acid has very poor oral bioavailability (<5%) due to high lipophilicity (logP ~7) and low aqueous solubility; Ergosterol-to-D2 conversion requires UV light exposure and is largely negated in dried indoor-stored specimens. Data gaps: Precise amino acid profiling for this specific species remains sparse; most nutritional analyses derive from closely related bracket fungi (e.g., Fomes fomentarius), and species-specific validated datasets are limited to a small number of European studies.

## Dosage & Preparation

No clinically studied dosage ranges exist due to absence of human trials. Commercial products suggest 500-3000 mg/day of powder or extract, but these recommendations are not validated by RCTs. Preclinical studies use 50-200 mg/kg in animals. Consult a healthcare provider before starting any new supplement.

## Safety & Drug Interactions

Birch polypore has no established human safety profile from clinical trials, and adverse effects in humans are not well-documented beyond anecdotal reports of mild gastrointestinal upset. Individuals with known mushroom allergies or birch pollen allergies should exercise caution due to potential cross-reactivity with birch-associated proteins. The fungus should be avoided during pregnancy and lactation given the complete absence of safety data in these populations, and its agaric acid content raises theoretical concerns about hepatotoxicity at high doses based on related species. Because [beta-glucan](/ingredients/condition/immune-support)s can modulate immune activity, concurrent use with immunosuppressant drugs such as cyclosporine or tacrolimus warrants medical supervision.

## Scientific Research

No human clinical trials, RCTs, or meta-analyses on Birch Polypore were identified in standard databases. The cited PMIDs (28579730, 27990079, 30930606, 28781509) correspond to unrelated research briefs with no mention of Piptoporus betulinus, limiting evidence to preclinical in vitro and animal studies.

## Historical & Cultural Context

Used for millennia in European folk medicine, most notably by Ötzi the Iceman (~5300 years ago) who carried it for parasite expulsion. Slavic and Germanic traditions employed it topically for wound healing and internally for cancer, infections, and diabetes through decoctions or as protective amulets.

## Synergistic Combinations

Reishi, Turkey Tail, Chaga, Vitamin D3, Zinc

## Frequently Asked Questions

### What did Ötzi the Iceman use birch polypore for?

Ötzi, the 5,300-year-old Copper Age mummy discovered in the Alps in 1991, was found carrying pieces of Piptoporus betulinus threaded on leather thongs. Researchers hypothesize he used it as an antiparasitic remedy, as his gut contained eggs of the whipworm Trichuris trichiura, and the mushroom's agaric acid is believed to have antiparasitic properties. This represents one of the earliest documented examples of medicinal fungus use.

### Does birch polypore kill cancer cells?

In laboratory (in vitro) studies, triterpenoids from birch polypore — including polyporenic acid C — have shown cytotoxic activity against human cancer cell lines such as HeLa (cervical) and MCF-7 (breast), with IC50 values typically in the range of 50–200 µg/mL. The proposed mechanism involves p53 upregulation and caspase-mediated apoptosis. However, no human clinical trials exist, and in vitro cytotoxicity does not reliably predict real-world anticancer efficacy.

### How do you take birch polypore — powder, tea, or extract?

Birch polypore is typically consumed as a dried powder, hot-water tea decoction, or dual-extract (water and ethanol) tincture to capture both water-soluble beta-glucans and alcohol-soluble triterpenoids. No clinically validated dosage exists for humans; commercial products commonly suggest 500–2,000 mg of dried extract daily, mirroring general medicinal mushroom conventions. Hot-water extraction is considered necessary to break down chitin cell walls and improve beta-glucan bioavailability.

### Is birch polypore the same as chaga or reishi?

No — birch polypore (Piptoporus betulinus), chaga (Inonotus obliquus), and reishi (Ganoderma lucidum) are three distinct fungal species that all grow on or near birch trees but belong to different genera and have different phytochemical profiles. Chaga is unusually rich in betulinic acid and melanin complexes, reishi is characterized by ganoderic acids, while birch polypore's signature compounds are polyporenic acids and piptamine. They share beta-glucan immunomodulatory activity but are not interchangeable.

### Are there any drug interactions with birch polypore supplements?

Birch polypore has not been studied for drug interactions in humans, but its beta-glucan content theoretically warrants caution when combined with immunosuppressant medications (e.g., cyclosporine, mycophenolate) because enhanced immune activation could counteract their intended effects. Some triterpenoids in related Ganodermataceae fungi inhibit CYP450 enzymes, raising a plausible concern that birch polypore triterpenoids could alter the metabolism of drugs processed by CYP3A4 or CYP2C9, though this has not been confirmed for this specific species. Anyone on anticoagulants, chemotherapy, or immunosuppressants should consult a physician before use.

### What is the difference between birch polypore cultivars and wild-harvested varieties?

Wild-harvested birch polypore is collected from birch trees in natural forests, while cultivated varieties are grown on sterilized substrates in controlled environments. Cultivated strains may have more consistent beta-glucan and triterpene profiles, though wild specimens are traditionally valued for potency. The cultivation method can affect the polysaccharide composition and bioactive compound concentration, with some evidence suggesting liquid culture extracts have higher bioavailability than mycelium-based products.

### How does the growing season affect birch polypore potency and compound content?

Birch polypore harvested in autumn typically contains higher concentrations of protective triterpenoids due to the fungus preparing for winter dormancy. Spring and early summer harvests may have different ratios of beta-glucans to other compounds, potentially affecting immune-modulating activity. The host birch tree's health, species, and geographic location also influence secondary metabolite accumulation in the fruiting body.

### What is the evidence quality for birch polypore's health benefits compared to other medicinal mushrooms?

Most birch polypore research is limited to in vitro and animal studies, with very few human clinical trials—making the evidence quality lower than for reishi or shiitake. The antimicrobial and immune-modulating mechanisms are theoretically supported by preclinical data on beta-glucan receptor activation, but human efficacy remains largely unproven. Current research suggests birch polypore warrants further investigation, but claims about cancer prevention or parasite elimination lack sufficient clinical evidence to support them in humans.

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*Source: Hermetica Superfoods Ingredient Encyclopedia — https://ingredients.hermeticasuperfoods.com*
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