Tea is often celebrated as a soothing, natural remedy. For centuries, it’s been brewed for everything from better sleep to clearer skin. But what if your favorite herbal infusion isn’t as harmless as it seems?
Surprisingly, not all teas are created equal. Some can contain compounds linked to serious health concerns, especially when consumed regularly or in large quantities. In this article, we’ll uncover 9 teas that health experts caution against—and why it might be time to clean out your tea shelf.
1. Comfrey Tea – Toxic to the Liver
Comfrey has long been used in folk medicine to heal wounds and reduce inflammation. However, it contains pyrrolizidine alkaloids (PAs)—toxic compounds that build up in the liver over time.
- A 2018 study in the Journal of Hepatology found that these alkaloids can cause liver damage and even lead to tumors in extreme cases.
- Regular consumption may result in chronic liver toxicity, especially in people with existing liver conditions.
Safer swap: Consider ginger tea for inflammation support, minus the toxicity.
2. Lobelia Tea – Dangerous for the Heart
Historically used for asthma and bronchitis, lobelia contains powerful alkaloids like lobeline, which act on the nervous system and cardiovascular functions.
- A 2010 Journal of Ethnopharmacology study linked lobeline to changes in heart rate and blood pressure.
- In high doses, it may lead to irregular heartbeat, dizziness, or even seizures.
If you have any heart-related conditions, this is one tea to avoid completely.
3. Chaparral Tea – A Threat to Liver and Kidney Health
Made from the creosote bush, chaparral tea contains NDGA (nordihydroguaiaretic acid)—a compound associated with liver and kidney toxicity.
- A 2018 Toxicology and Applied Pharmacology report noted that NDGA and certain flavonoids can cause oxidative stress, leading to cell damage.
- Regular intake may impair your body’s natural detox systems, resulting in long-term harm.
Pro tip: Milk thistle is a gentler alternative for liver support.
4. Germander Tea – Linked to Hepatitis and Heart Strain
Germander may sound exotic, but it carries serious risks.
- A 1992 study in Annals of Internal Medicine documented multiple cases of germander-induced hepatitis.
- It also contains compounds that may harm the heart, kidneys, and digestive tract, especially in large or long-term doses.
Instead, try: Peppermint tea for digestion or hibiscus for heart health.
5. Sassafras Tea – Banned for a Reason
Sassafras has a rich history in American herbal medicine, but its main compound, safrole, is classified as a potential carcinogen.
- The FDA banned safrole as a food additive due to its cancer risk.
- A 2016 Journal of the National Cancer Institute study found that safrole caused liver tumors in animals.
Skip this one entirely, especially since safer alternatives like rooibos or cinnamon tea are widely available.
6. Pennyroyal Tea – Harmful to Liver, Lungs, and Kidneys
Pennyroyal was once a go-to for cold relief and menstrual cramps—but its dangers outweigh the benefits.
- Contains pulegone, which converts into toxic metabolites in the body.
- A 2012 Human & Experimental Toxicology study confirmed its liver and lung toxicity.
- May even cause kidney damage or reproductive effects.
Safe tip: If you need relaxation or hormone support, opt for chamomile or raspberry leaf tea instead.
7. Bitter Orange Tea – Spikes Blood Pressure
Often marketed for weight loss, bitter orange tea contains synephrine, a stimulant similar to ephedra.
- Can raise heart rate and blood pressure, according to a 2012 Journal of Clinical Pharmacology review.
- Combined with other stimulants, it poses a higher risk of cardiac stress or arrhythmias.
Avoid especially if you have high blood pressure or take heart meds.
8. Ephedra Tea – A Heart Health Hazard
Also known as ma huang, ephedra contains ephedrine and pseudoephedrine, both potent stimulants.
- These compounds can increase heart rate, blood pressure, and the risk of stroke or seizure, according to a 2005 American Journal of Medicine study.
- Ephedra is now banned in dietary supplements in the U.S. due to safety concerns.
Note: Even in tea form, the risks outweigh any potential benefit.
9. Kombucha – Proceed with Caution
Kombucha is trendy for its probiotic benefits—but it’s not risk-free.
- Improper home brewing can lead to contamination, mold, or dangerous acid levels.
- A 2019 Journal of General Internal Medicine report cited cases of lactic acidosis from poorly brewed kombucha.
It also naturally contains small amounts of alcohol, which may not be suitable for everyone, especially pregnant women or those with liver issues.
If you enjoy kombucha, buy from reputable brands and avoid home fermentation unless trained.
Safe Tea Habits and What to Watch For
To enjoy tea safely:
- Check the source: Always buy from reputable brands that follow safety guidelines.
- Moderation matters: Even healthy herbs can have side effects in high doses.
- Read the label: Look for disclaimers, FDA warnings, or restricted substances.
- Consult your doctor if you’re on medications, pregnant, or have a health condition.
Share This Tea Truth
If you’re a tea lover, or know someone who is, share this article to help protect their health. Knowledge is power—and in this case, possibly life-saving.
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Disclaimer
This article is for informational purposes only and does not substitute professional medical advice. Always consult your healthcare provider before making dietary or lifestyle changes, especially if you have a medical condition or are taking medication.
