Chaga Tea: Benefits, How to Make It and Oxalate Safety

Chaga tea is a hot water brew made from chaga (Inonotus obliquus), a dark, woody fungus that grows on birch trees, and it is caffeine-free. People drink it for its earthy, slightly bitter taste and for the plant compounds it carries, mainly phenolics and polysaccharides. Most chaga research has been done in cells and animals, measuring antioxidant activity, immune signaling and blood sugar markers (Memorial Sloan Kettering). One lab study found that chaga powder steeped for six minutes in boiling water gave one of the most active extracts it tested (Alhallaf and Perkins, 2022). The safety point everyone should know: chaga is very high in oxalates, and kidney injury has been reported in people who took large daily amounts for months (Lee et al., 2020).

For chaga's chemistry and the full research picture, see our Chaga ingredient page.

Key Takeaways

• What it is: chaga tea is chaga chunks or powder steeped or simmered in hot water. It has no caffeine.
• What research measured: antioxidant, immune signaling and blood sugar effects, mostly in lab and animal studies (Memorial Sloan Kettering).
• Brewing matters: in a lab comparison, powder steeped 6 minutes at 100 °C was among the most active extracts on inflammatory signaling markers in mouse immune cells (Alhallaf and Perkins, 2022).
• Oxalates are the main caution: one tested chaga powder had 14.2 g of oxalate per 100 g, and kidney injury has been reported after months of heavy daily use (Lee et al., 2020; Kwon et al., 2022).
• Check your medicines: chaga may add to the effects of blood thinners and blood sugar medicines (Memorial Sloan Kettering).

What Is Chaga Tea?

Chaga is not a typical cap-and-stem mushroom. It is a sclerotium, a hard, black, cracked mass that the Inonotus obliquus fungus forms on living birch trees in cold northern forests. Inside it is rusty orange and corky. People in Russia and northern Europe have brewed it as a folk tea for a long time, and today it is sold as chunks, ground powder, tea bags, extracts and an ingredient in mushroom coffees and blends.

Chaga tea is simply chaga steeped or simmered in hot water. The water pulls out water-soluble compounds, mainly polysaccharides and phenolics, which give the tea its dark color. Alcohol-based extracts pull out more of the fat-soluble triterpenes, so a cup of tea and an alcohol tincture are not the same thing. For a broader look at how extraction changes what you get, read mushroom extracts vs powders.

Chaga Tea Benefits: What Research Has Measured

Chaga is studied for three main areas, and it helps to know what kind of research sits behind each one.

• Antioxidant activity: chaga's phenolic compounds and dark melanin pigments show antioxidant activity in lab tests (Memorial Sloan Kettering).
• Immune signaling: chaga polysaccharides and extracts change immune and inflammatory signaling in cell and animal studies. In a 2022 lab study, a tea made by steeping chaga powder in 100 °C water for 6 minutes lowered nitric oxide and inflammatory cytokines in stimulated mouse immune cells, more than several longer alcohol and water extraction methods did (Alhallaf and Perkins, 2022).
• Blood sugar: lab and animal studies have looked at chaga's effects on glucose, which is also why it may add to blood sugar medicines (Memorial Sloan Kettering).

Chaga is often grouped with other functional mushrooms; our guide to adaptogenic mushrooms shows where it fits, and our Immune System Function and Daily Support hub covers daily habits that support immune function. For how chaga compares with reishi, see chaga vs reishi. For a broader look at chaga beyond tea, see our guide to chaga mushroom benefits. To see how chaga sits next to a gut and immune mushroom, our guide to chaga vs turkey tail compares the two.

How to Make Chaga Tea

There are two common ways to brew it, depending on whether you have powder or chunks.

From powder or tea bags (quick method):

1. Bring water to a boil and let it settle for a moment.
2. Add a small amount of chaga powder, about 1 teaspoon per cup, to a mug or tea strainer.
3. Pour the hot water over it and steep for about 6 minutes, the time that gave a strong extract in the lab comparison (Alhallaf and Perkins, 2022).
4. Strain through a fine filter or let the sediment settle, then drink.

From chunks (simmer method):

1. Rinse a few small chunks, roughly thumb-sized.
2. Add them to a pot of water and bring it to a low simmer, not a hard boil.
3. Simmer for an hour or longer, until the water turns dark brown.
4. Strain, and dry the chunks if you plan to reuse them.

Chaga tea tastes earthy and mildly bitter with a faint vanilla note. A splash of milk, cinnamon or a little honey softens it. If you already like warm mushroom drinks, our guide to mushroom hot chocolate and our comparison of mushroom coffee vs regular coffee offer other ways to drink mushrooms.

Form	How you use it	Good to know
Powder or tea bags	Steep in just-boiled water, about 6 minutes	Fast; powder strength varies by brand
Chunks	Simmer an hour or more	Traditional; strength hard to judge
Alcohol extract or tincture	Drops in water	Pulls more triterpenes than water does
Concentrated extract capsules	Swallow with water	Measured amount per serving; no brewing

Chaga Tea Safety: Oxalates and Your Kidneys

Chaga's biggest safety issue is oxalate, a compound that can bind calcium and build up in the kidneys. In one case report, a chaga powder a man had used for years contained 14.2 g of oxalate per 100 g, and other commercial chaga powders tested at 2.8 and 11.2 g per 100 g. He had taken 3 g of powder a day for four years and then 9 g a day for another year, and his kidney function did not recover (Lee et al., 2020). In a second case, a 69-year-old man took 10 to 15 g of chaga powder a day, along with 500 mg of vitamin C, for three months and developed acute kidney injury linked to oxalate. His kidney function recovered after treatment (Kwon et al., 2022).

Both cases involved swallowing many grams of powder every day for months or years, far more than an occasional cup of strained tea. Still, they show why amount and frequency matter:

• Keep chaga tea to a cup now and then rather than several strong cups every day.
• Do not eat the sediment or stir large amounts of raw powder into drinks daily.
• Think twice about pairing it with high-dose vitamin C; the 2022 case also involved 500 mg of vitamin C a day.
• Drink plenty of water.

Who Should Skip Chaga Tea or Ask First

Talk with a clinician before drinking chaga tea regularly if you:

• Have kidney problems or a history of kidney stones.
• Take blood thinners or antiplatelet medicines, since chaga may raise bleeding risk (Memorial Sloan Kettering).
• Take medicines that lower blood sugar, since lab tests showed added glucose-lowering effects (Memorial Sloan Kettering).
• Have surgery coming up.
• Are pregnant or breastfeeding.
• Have an autoimmune condition or take medicines that act on the immune system.

Chaga Tea vs Chaga Extract Capsules

Tea is a pleasant ritual, but its strength depends on the powder, the water and the steep time. Concentrated extracts give a measured amount in every serving. An 8:1 extract means about 8 parts of dried mushroom went into 1 part of finished extract; our guide on what 8:1 extract means explains how to read that on a label.

Forage is our blend of 8:1 fruiting body mushroom extracts with Himalayan shilajit and ashwagandha root extract, taken as 2 capsules a day in the morning. Each 2-capsule serving includes 150 mg of 8:1 chaga extract alongside other functional mushrooms such as lion's mane, cordyceps and reishi. If you want a warm mushroom drink instead, Mushroom Cacao is a mushroom hot chocolate made with 500 mg each of 8:1 lion's mane and cordyceps fruiting body extracts per serving. It does not contain chaga. You can also read our guide to reishi tea and liver safety if you are comparing mushroom teas.

Frequently Asked Questions

What does chaga tea do?

Chaga tea delivers water-soluble chaga compounds, mainly phenolics and polysaccharides. Research on these compounds has measured antioxidant activity, immune signaling and blood sugar markers, mostly in cells and animals (Memorial Sloan Kettering).

Does chaga tea have caffeine?

No. Chaga is a fungus, not a tea plant, so chaga tea is naturally caffeine-free unless it is blended with black or green tea or coffee.

Can I drink chaga tea every day?

Because chaga is high in oxalate, daily heavy use is the pattern linked to kidney problems in case reports (Lee et al., 2020). An occasional cup is a more cautious approach, and anyone with kidney concerns should ask a clinician first.

How long should I steep chaga tea?

About 6 minutes in just-boiled water for powder, or an hour or more at a simmer for chunks. The 6-minute powder tea was among the most active extracts in a lab comparison (Alhallaf and Perkins, 2022).

What does chaga tea taste like?

Earthy and mildly bitter, a little like weak coffee, with a faint vanilla note. Milk or cinnamon rounds it out.

Can you reuse chaga chunks?

Chunks can be simmered two or three times, dried between uses. Each brew will be lighter than the last.

Is chaga tea safe with medications?

It may add to the effects of blood thinners and blood sugar medicines (Memorial Sloan Kettering). Check with your clinician or pharmacist if you take either.

Is chaga tea better than chaga capsules?

Tea is a ritual with variable strength; extract capsules give a set amount per serving. See mushroom extracts vs powders for the trade-offs.

Sources

1. Memorial Sloan Kettering Cancer Center. Chaga Mushroom (About Herbs). Updated 2023. MSK
2. Alhallaf W, Perkins LB. The Anti-Inflammatory Properties of Chaga Extracts Obtained by Different Extraction Methods against LPS-Induced RAW 264.7. Molecules. 2022;27(13):4207. DOI
3. Lee S, Lee HY, Park Y, et al. Development of End Stage Renal Disease after Long-Term Ingestion of Chaga Mushroom: Case Report and Review of Literature. J Korean Med Sci. 2020;35(19):e122. DOI (PubMed 32419395)
4. Kwon O, Kim Y, Paek JH, et al. Chaga mushroom-induced oxalate nephropathy that clinically manifested as nephrotic syndrome: A case report. Medicine (Baltimore). 2022;101(10):e28997. DOI (PubMed 35451393)

Our products are not intended to diagnose, treat, cure or prevent any disease. This article is for education only and is not medical advice.