Chaga vs Reishi: Key Differences

Quick answer

Reishi has one early finding, a rise in some immune cell counts with a purified beta-glucan at 200 mg a day. Chaga has no trial in people and no studied amount. Both are woody tree fungi, and the harm reported for each involved powders: kidney damage for chaga, rare liver injury for reishi.^1,2,3

Key facts

LiverTox gives reishi's usual amount as 500 mg to 3 g a day. No daily amount has been set for chaga.^2,3
A 2025 review pooled 17 randomized trials of reishi in 971 people and rated the certainty of every finding very low.⁴
Chaga extracts from Finland, Russia and Thailand all had oxalic acid as their main organic acid. Reishi is known for polysaccharides and bitter triterpenes.^2,5
Reishi's ganoderic acids appeared in the blood within 5 to 10 minutes of a 3 g dose and halved in under 40 minutes. We found no such measurement for chaga.⁶

Chaga and reishi, line by line

Chaga and reishi compared^2,4,5,6,7
	Chaga	Reishi
Other names	Inonotus obliquus, chaga mushroom	Lingzhi, Ganoderma lucidum, Ganoderma lingzhi, red reishi
Where it grows	As a parasite on birch and other trees	At the base of trees and on stumps; farmed on logs, sawdust or wood chips
Compounds named in the research	Oxalic acid as the main organic acid; polysaccharides, phenolic compounds and peptides in laboratory studies	Polysaccharides, mostly beta-glucans, and bitter triterpenes called ganoderic acids
Human evidence	None of chaga alone	17 randomized trials pooled in 2025, certainty very low
Amounts	None studied	500 mg to 3 g a day is the usual range; trials used 200 mg to 11.2 g
What happens to a dose	Not measured in the sources we read	Ganoderic acids reach the blood in minutes and halve in under 40 minutes
What has been reported	Oxalate kidney damage after daily powder	Rare liver injury, usually 1 to 2 months after starting

What each one contains

Reishi contains polysaccharides, triterpenoids, sterols, fatty acids, proteins and trace elements. Which of them, if any, act in the body is unknown.²

Water and alcohol extracts of chaga from Finland, Russia and Thailand all contained oxalic acid as their main organic acid, the most in a Russian water extract.⁵

The two chemistries point in different directions. Reishi's compounds are the ones its research is organized around, and no one knows which of them, if any, act in the body. Chaga's best documented chemical fact is its oxalate, which has been linked to harm rather than to anything graded as a benefit.^2,3

What has been shown in people

Reishi has one graded finding, and it belongs to a purified extract rather than to the whole mushroom.

A purified reishi beta-glucan may raise counts of some immune cells in healthy adults*^1,8,9,10

Early evidence

In a randomized, placebo-controlled trial in healthy adults aged 18 to 55 (157 enrolled, 135 finished), 200 mg a day of a purified reishi beta-glucan for 12 weeks raised counts of several kinds of T cells and natural killer cells more than placebo. It did not measure whether people fell ill less often, and a company paid for it. A trial in young children who ate a yogurt with reishi beta-glucans found a similar rise. Whole reishi did not show this: 1.44 g a day for 4 weeks, and 4 g a day of an extract for 10 days, left immune measures unchanged in small trials.

Amount studied: 200 mg a day of purified reishi beta-glucan, for 12 weeks

A 2025 pooled analysis of 17 randomized trials in 971 people rated the certainty of every reishi finding as very low.⁴

For chaga there is nothing to grade. The only human work we found was a one-time trial of an herb mixture and a laboratory test on blood cells, and neither gave chaga alone to people over time.^11,12

Amounts and what happens to a dose

Trials in healthy adults gave 0.72 to 4 g a day of whole reishi preparations or extracts, for 10 days to 4 weeks.^9,10,13,14

A 2025 review of 17 randomized trials found daily amounts from 200 mg to 11.2 g, taken for 1 to 24 weeks.⁴

Chaga offers no matching list. In the chaga sources we read, the only amounts in grams come from case reports of people who had kidney damage, at 3 to 15 g of powder a day for 3 months to 5 years. Those are descriptions of harm, not amounts anyone set out to test.^3,7

Powders, extracts and purified fractions

Reishi is sold as an extract on its own or in blends with other herbs, and as powders, dried slices and spore powder.²

A purified reishi beta-glucan concentrates one group of compounds. The rise in immune cells seen with it did not appear in small trials of whole reishi at 1.44 to 4 g a day.^1,9,10

Chaga is sold as a ground powder, and every published case of kidney damage involved chaga powder taken daily.^3,7,15

A shared pattern is worth noting. In both mushrooms the reported harm clustered around powders. Two of the reishi liver cases began after a switch to a powdered product, and all the chaga kidney cases involved daily powder.^2,7

What's in ours

Our Mushroom Complex gives reishi its own row, 266 mg of extract from the fruiting body with no beta-glucan figure, so it cannot be matched to the 200 mg purified beta-glucan in the trial. Chaga sits inside a shared blend row with five other mushrooms. We make no claim for either in it.¹

Kidney, liver and who should ask first

Oxalate nephropathy, kidney damage from oxalate crystals, has been reported in at least three people who took chaga powder every day for months or years.^3,7,15

A 49-year-old man who took 3 g of chaga powder a day for four years, then 9 g a day for a year, developed kidney failure and was still on dialysis 18 months later.³

Rare cases of liver injury have been reported, usually 1 to 2 months after starting reishi, with tiredness, nausea, stomach pain, poor appetite, dark urine or yellowing of the skin and eyes. Most people recovered within 1 to 3 months of stopping, but one woman died.²

In trials of 1.4 to 3 g a day for 12 to 16 weeks in adults with type 2 diabetes, side effects were reported somewhat more often with reishi than with placebo, a difference that may be due to chance. None was serious.¹⁶

Do not take chaga if you have kidney disease or have had kidney stones, unless your kidney doctor agrees³
Do not take reishi if you have had a liver reaction to it before, and ask first if you have liver disease²
Ask first about either if you take a blood thinner or antiplatelet medicine, or have surgery planned^17,18
Ask first about either if you take medicine for blood sugar: laboratory and animal studies point that way for both^2,19
Ask first about reishi if you take medicines that suppress the immune system, or if you are allergic to mushrooms or molds¹
Ask first if you are being treated for cancer, or are pregnant or breastfeeding

Questions people ask

What is the difference between chaga and reishi?

Chaga is a fungus that lives on birch and other trees and is known chemically for oxalic acid. Reishi, or lingzhi, grows at the base of trees and on stumps, and is known for polysaccharides and bitter triterpenes. Reishi has one early graded finding. Chaga has none.^1,2,5,7

Which has more studies, chaga or reishi?

Reishi. A 2025 review pooled 17 randomized trials in 971 people, although it rated the certainty of every finding very low. We found no trial of chaga alone in people.^4,11

Which one is a concern for the liver and which for the kidneys?

Reishi is a possible rare cause of liver injury, according to LiverTox. Chaga is the one linked to kidney damage, through its high oxalate content. Ask your doctor first if you have liver or kidney problems.^2,3

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Sources

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.

This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.