The liver works quietly around the clock, performing hundreds of functions that keep the body running. But when it comes to herbal medicines and supplements, “natural” does not always mean harmless.
At the 8th Cebu Cancer Fair on Aug. 29, 2026, at Oakridge Pavilion in Mandaue City, internist-gastroenterologist Dr. Karen Batoctoy discussed liver injury linked to herbal medicines and dietary supplements.
“Herbal or medicinal plants are not always safe; many plants are toxic,” said Batoctoy.
Here are some things to keep in mind before reaching for that bottle of supplements:
1. Natural does not automatically mean safe
Herbal medicines, traditional remedies and dietary supplements are often perceived as gentler alternatives to conventional medicines. But some can cause drug-induced liver injury, or Dili.
Batoctoy cited information from the US Drug-Induced Liver Injury Network indicating that herbal products account for around 10 percent to 20 percent of drug-induced liver injury cases.
The effects can range from mild increases in liver enzymes to severe acute liver failure that may require a transplant or, in some cases, result in death.
This does not mean every herbal product is harmful. It means supplements should be approached with the same caution as medicines.
2. More is not always better
Some of the products discussed in Batoctoy’s presentation included green tea extract, turmeric or curcumin, ashwagandha, kava kava, garcinia cambogia and black cohosh.
Green tea extract, particularly in weight-loss products, has been associated with liver injury. Turmeric and curcumin supplements have also been linked to reports of acute liver injury, particularly with high-dose use.
Batoctoy presented clinical cases and research involving turmeric-associated liver injury, including reports from the Drug-Induced Liver Injury Network.
The important distinction is between consuming turmeric as food and taking a concentrated supplement containing high amounts of curcumin.
Dose matters. More is not necessarily better.
3. Tell your doctor what you are taking
When consulting a doctor, do not leave out herbal products or dietary supplements.
Knowing everything a patient takes can help doctors investigate abnormal liver tests and determine whether a medication or supplement could be contributing to liver injury.
This is especially important when several medicines or supplements are being taken at the same time.
4. Pay attention to product quality
Not all supplements are made or regulated in the same way.
Batoctoy emphasized the importance of being mindful of product quality, especially when choosing herbal medicines and dietary supplements.
A product being sold as a supplement does not automatically mean it is risk-free.
5. Know the warning signs
Certain symptoms should not simply be dismissed as a normal reaction to a supplement.
Watch out for unusual fatigue, nausea, abdominal discomfort, dark urine or yellowing of the skin and eyes.
If these symptoms appear, seek medical advice rather than simply stopping and restarting the product on your own.
6. Ask before you add another supplement
Before taking an herbal medicine or dietary supplement, talk to your doctor, particularly if you are already taking prescription medicines or have an existing medical condition.
The goal is not to avoid every herbal product. It is to make informed choices and remember that the liver, like the rest of the body, can be affected by what we put into it. S