Reishi Mushroom Guide: Benefits, Side Effects, Safety and Research

Maybe it started with a post about calmer nights, or a friend who swears by a reishi gummy. Maybe you already take medicine and want to know whether a mushroom can sit alongside it. Either way, you want to know what is real before you spend money or add something new.

Reishi has a long history of use and a growing body of research, but most of that research is early. The studies sort into lab work, animal work and a small number of human trials, and the human trials are few and mixed. This guide walks you through what the studies found, what daily use looks like, what to check on a label, and when to bring in a clinician.

Reishi, Ganoderma lucidum, is a mushroom that has been used in traditional Chinese medicine for centuries. Modern research has not established a clear benefit for any particular condition in people, and the long-term safety questions are still open.

Step 1: Understand what reishi is

You want to know what this mushroom is and why it shows up in so many products. Start with the name, because labels use more than one.

The 2017 review in the International Journal of Medicinal Mushrooms calls it the lingzhi or reishi medicinal mushroom, Ganoderma lucidum. You will see both names in articles and on packaging.

A 2021 comprehensive review in Phytotherapy Research lists its main compounds: polysaccharides (alpha and beta glucans), triterpenoids such as ganoderic acids, sterols, proteins and nucleosides. A 2023 review in Chinese Herbal Medicines describes triterpenoids as the major constituents. That is why labels talk about these two groups.

Once you know what the mushroom is, the next question is what the human studies actually found.

Step 2: See what the research actually shows

You want to know whether reishi does anything for you. Here is the honest picture, with the study types shown.

Most of the research is not in people. The 2016 review on reishi and cancer says almost all data come from laboratory and preclinical studies, and that the few clinical studies are questionable. The 2021 review says most studies are preclinical and that quality clinical data are still needed.

The pooled human data in this evidence come from cancer patients. A Cochrane systematic review and meta-analysis pooled five randomized trials and found reishi given with chemotherapy or radiotherapy was linked to a possible better tumour response, but the result was uncertain. It reported small rises in some immune cell measures, better quality of life in four studies, and no clear effect on long-term survival. Its authors say there is not enough to justify reishi as a first-line cancer treatment. An earlier 2012 Cochrane version asked the same question.

Two registered trials show where new research is heading. A ClinicalTrials.gov record describes a recruiting phase 2 study of reishi extract for fatigue and joint or muscle pain in breast cancer patients on aromatase inhibitors, with 80 people planned. A second record describes a 28-day study of lion’s mane alone, a lion’s mane and reishi blend, and placebo in stressed or anxious women aged 18 to 26. It is marked completed with 84 planned or enrolled, but the record lists design rather than results, and its summary also mentions 135 women to be recruited, so check the record for current numbers.

If you want to judge a study yourself, How to Read a Clinical Study walks through the parts to check.

Does reishi really lower cortisol?

The studies here do not show that reishi lowers cortisol in people. The 2021 review lists stress-related areas among those it explores, but describes that work as mostly preclinical. A cortisol claim on a product page is the seller’s statement.

What are the health benefits of Lingzhi?

Lingzhi is the Chinese name for the same mushroom, Ganoderma lucidum. The research points to immune-cell changes and quality-of-life reports in cancer patients, plus lab work on many other conditions. None of that is a settled benefit for you.

What does Ganoderma lucidum do for the body?

The 2021 review lists diabetes, inflammation, epilepsy, neurodegeneration, cancer, anxiety, sedation, heart disease, depression, liver disease and immune disorders among the areas studied. Most of that work is preclinical. Read the list as research topics, not as proven effects.

Is Ganoderma tsugae the same as reishi?

The studies here cover Ganoderma lucidum only. They do not answer questions about other Ganoderma species, so do not assume findings carry over.

Does reishi get rid of belly fat?

The studies here do not measure belly fat, so they do not show that reishi reduces it. If weight is your concern, a clinician can help you look at the cause.

Knowing what the research says, the next question is what daily use looks like.

Step 3: Work out what daily use looks like

You are asking when to take reishi and what happens if you take it every day. These are fair questions, and the answers are more limited than most product pages suggest.

When should you have reishi?

The studies here do not set a best time of day, and they do not give a standard dose you can rely on. Follow the product label for timing, and ask a clinician what fits your situation. If you are unsure how much is too much, our supplement facts panel guide shows where dose appears on a label.

What happens if you take reishi every day?

Long-term safety is not established. The 2021 review says studies on chronic use, interactions and other safety questions are missing. In the Cochrane review, reishi was generally well tolerated, with only minor adverse events.

Can reishi help with stress, sleep or mood?

Stress, anxiety and sedation appear among the research topics in the 2021 review, but that work is mostly preclinical. The registered stress and anxiety trial above has not published results in this guide. If sleep is your goal, our guide compares reishi and lion’s mane for sleep.

Daily use only makes sense if it fits your medicines and health, so that is the next step.

Step 4: Check medicines and cancer care before you start

This is where guessing causes the most harm. Take these checks seriously before you add reishi to anything you already take.

A 2017 systematic review looked at reishi and its products alongside chemotherapy, including effects on chemotherapy and its toxicity. If you are in cancer treatment, bring reishi to your oncology team before you take it.

For any other medicine, ask your pharmacist or doctor before combining it with reishi. Bring the product label so they can see the exact ingredients and amounts. Our immune-suppressing medicines guide lists the questions to ask.

Supplements face lighter oversight than prescription drugs. A 2023 narrative review in Innovations in Pharmacy argues that FDA oversight of dietary supplements is less strict than for prescription medicines. It reports 79,071 adverse events linked to supplements of all kinds reported to the FDA between 2004 and 2021. So the label and your clinician should carry more weight than a product page.

With safety questions in hand, you can look at formats and labels.

Step 5: Choose a format and read the label

You are ready to look at products. Reishi is sold in supplement products, including capsules, and the label tells you what is inside.

Look for the species name, the part used, the extract type and the amount per serving. A blend that does not state the reishi amount per serving cannot tell you how much reishi you are getting. Our tincture and drops guide explains common label terms.

Some products pair reishi with other mushrooms. Check each one on its own label. A product page that says a product helps sleep or stress is making the seller’s statement, and the studies above do not confirm it for any specific product.

To separate marketing from ingredient research, read Ingredient Evidence vs. Marketing Claims.

Once a product fits your label checks, the last step is the seller’s terms.

Step 6: Check price, refunds and the label before you order

Look at the seller’s own pages for the current price, shipping, cancellation and refund terms. Prices change, so check the checkout for today’s price rather than trusting an older article.

Refund and subscription terms matter as much as price. Read how to cancel any subscription before you accept it. Keep your order number and a photo of the label.

If a page does not show the full label, ask the seller for it in writing before you order.

Your next step

1. Write down the problem you want to address, and talk it through with a clinician.
2. If you take any medicine or are in cancer treatment, ask about reishi before you start.
3. Read the full label for species, part used, extract type and amount per serving.
4. Check the seller’s price, shipping and refund terms at checkout.
5. If you notice a side effect, use our when to stop guide and ask a clinician.

Disclosure: some links on this page go to seller product pages, which are sponsored links.

Every guide on this topic

Reishi basics and research

• What Is Reishi Mushroom?: the mushroom and its names.
• Reishi Complete Research Profile: compounds, immune research and dosage context.
• Reishi Mushroom Explained: effects, side effects and daily use.
• Lion’s Mane, Cordyceps, and Reishi Compared: what each mushroom is studied for.
• Reishi vs Lion’s Mane for Sleep: sleep-focused comparison.
• What Is Mushroom Extract?: what extract means on a label.
• What Is Cordyceps Mushroom?: uses, side effects and safety.
• A Mushroom Trial Uses a Different Species Than the Label: why species matters.
• Cell and Animal Mushroom Research: what it can and cannot tell people.

Dose, safety and side effects

• Mushroom Gummies and Medications: The Interaction Guide: categories to raise with clinicians.
• Mushroom Gummies Safety Guide 2026: interactions and contraindications.
• Mushroom Complex Safety Guide 2026: capsule risks and interactions.
• When to Stop Taking Mushroom Supplements: warning signs.
• Mushroom Supplements and Immune-Suppressing Medicines: questions to ask.
• Are Adaptogens Safe?: side effects and research.
• How Much Lion’s Mane Is Too Much?: dose and safety.
• Reading the Supplement Facts Panel: where dose appears.
• Mushroom Supplement Allergen Statements: what free-from claims cover.

Formats and label reading

• What to Look for Before Buying Reishi Gummies: label checklist.
• Mushroom Tincture Guide: benefits, labels and safety.
• Mushroom Drops Guide: drops, side effects and labels.
• Best Functional Mushroom Supplements: Label Guide: reading labels across products.
• Functional Mushroom Supplements: Risks and Choosing: how to choose.
• Functional Mushroom Blend Names: finding each species and dose.
• Polysaccharides and Beta-Glucans Are Not Interchangeable: label claims explained.
• What Are Mushroom Gummies?: plain-language guide.
• What Is a 10-in-1 Mushroom Powder?: buyer’s guide.
• What Is Shrumfuzed?: plain-language gummy guide.
• Mushroom Gummies: Reviews, Results and Side Effects: what to expect.
• Legal Mushroom Gummies Guide: legal status.
• Do Mushroom Gummies Make You Trip?: label guide.
• Om Mushroom Guide: Ingredients, Price and Safety: ingredients and price.
• Flow Mushroom Pouches Guide: ingredients, safety and price.
• Adaptogen Vitality Gummy Label Guide: ingredients and research.

Other mushrooms and related questions

• Lion’s Mane Tincture Guide: research, dose and labels.
• Lion’s Mane Gummies Guide: benefits, side effects and choosing.
• Lion’s Mane Supplement Guide: benefits, side effects and dose.
• Does Lion’s Mane Help Brain Fog?: what the research covers.
• Shiitake Mushroom Powder Guide: benefits, labels and safety.
• Chaga Supplement Guide: benefits, side effects and safety.
• Mushroom Supplements for Inflammation and Joint Health: what the research covers.

By TopShelfMushrooms.com Editorial Team

This article is for general information purposes only and does not constitute medical advice. Consult your doctor or qualified healthcare provider before making changes to your health routine.