Who should not take turmeric? Understanding the risks and contraindications

October 16, 2025 •

3 min read

According to the Therapeutic Goods Administration (TGA), there have been rare but documented cases of liver injury linked to medicinal dosages of turmeric or curcumin supplements. While a beloved spice for its potent anti-inflammatory properties, knowing who should not take turmeric is crucial for preventing serious health complications, particularly with concentrated supplements.

Quick Summary

Turmeric is contraindicated for certain individuals and those on specific medications. Key concerns include gallbladder problems, bleeding disorders, iron deficiency, and kidney issues, particularly when consumed in supplemental, high-dose forms. Pre-existing health conditions and specific drug interactions warrant caution.

Key Points

Bleeding Risk: Individuals with bleeding disorders or on blood-thinning medication should avoid high-dose turmeric, as it can increase the risk of excessive bleeding.
Gallbladder and Liver Concerns: People with gallstones, bile duct obstructions, or existing liver disease should exercise caution or avoid turmeric supplements, which can exacerbate these conditions.
Kidney Stone Risk: Due to its oxalate content, high intake of turmeric supplements can increase the risk of kidney stone formation in susceptible individuals.
Iron Absorption: Turmeric can inhibit iron absorption, posing a risk for those with iron deficiency or anemia.
Drug Interactions: Curcumin interacts with numerous medications, including blood thinners, diabetes drugs, chemotherapy, and antacids, potentially altering their effectiveness.
Special Populations: Pregnant and breastfeeding women, as well as those undergoing surgery, should avoid medicinal doses of turmeric.
Supplement vs. Spice: The risks associated with turmeric are primarily linked to high-dose supplements, whereas culinary use is generally considered safe for most people.

What is Turmeric?

Turmeric, a vibrant yellow spice derived from the Curcuma longa plant, is widely used in South Asian cuisine and traditional medicine. Curcuminoids, especially curcumin, are the primary active compounds responsible for its medicinal effects. While culinary use of turmeric is generally considered safe, high-dose supplements containing concentrated curcuminoids require careful consideration due to an increased risk of side effects and interactions.

Who Should Be Cautious or Avoid Turmeric?

Certain health conditions and situations make it advisable to avoid or be cautious with high-dose turmeric or curcumin supplements. Consultation with a healthcare professional is recommended before starting any new supplement.

Individuals with Gallbladder or Liver Issues

High doses of turmeric can stimulate the gallbladder, increasing bile production and potentially worsening symptoms for individuals with gallbladder issues like gallstones or bile duct obstruction. While some research suggests curcumin may help prevent gallstones in healthy individuals by promoting bile flow, it can aggravate the condition when stones are present. Although rare, liver injury has been linked to high-dose curcumin supplementation, particularly with enhanced absorption formulations or in individuals with pre-existing liver conditions.

People with Bleeding Disorders or on Blood Thinners

Turmeric has mild anticoagulant properties, which can slow blood clotting. This poses a risk for individuals with bleeding disorders or those taking anticoagulant or antiplatelet medications such as warfarin, clopidogrel, or aspirin, potentially increasing bruising and bleeding risk.

Those with Iron Deficiency Anemia

Curcumin can reduce the absorption of iron in the digestive system. This is a concern for individuals with iron deficiency or anemia, as it could worsen the condition. A case study indicated that stopping high-dose turmeric supplementation improved iron levels in an anemic individual. Therefore, taking high-dose turmeric with oral iron supplements is not advised.

Individuals Prone to Kidney Stones

Turmeric contains oxalates, which can contribute to the formation of calcium oxalate kidney stones. High intake of turmeric supplements can elevate urinary oxalate levels, increasing the risk of stone formation, especially in susceptible individuals.

Pregnant or Breastfeeding Women

While dietary amounts are safe, high-dose turmeric supplements are not recommended during pregnancy due to potential uterine-stimulating effects that could increase miscarriage risk. Insufficient safety data exists for medicinal quantities during breastfeeding, so avoidance is typically advised.

Patients Scheduled for Surgery

Due to its effect on blood clotting, it is generally recommended to stop taking turmeric supplements at least two weeks before any planned surgery to minimize the risk of excessive bleeding.

Comparison: Dietary vs. Supplemental Turmeric


Feature	Culinary/Dietary Turmeric	Supplemental Turmeric/Curcumin
Dose	Small amounts used as a spice in food.	High, concentrated doses, often standardized for curcuminoids.
Concentration	Low concentration of curcumin.	High concentration of curcumin.
Risk of Side Effects	Very low for most people; generally recognized as safe (GRAS).	Higher risk, especially for digestive issues, liver injury, and potential drug interactions.
Risk of Drug Interactions	Low to none, as the amount is typically too small to cause significant effects.	High potential for interactions, especially with blood thinners, diabetes medications, and more.
Effect on Conditions	Unlikely to cause problems in most at-risk individuals due to low dose.	Can exacerbate pre-existing conditions like gallstones, bleeding disorders, and iron deficiency.

Potential Drug Interactions

High-dose turmeric and curcumin can interact with various medications. Drug classes that may be affected include:

Blood Thinners: Anticoagulants and antiplatelets.
Diabetes Medications: May enhance blood sugar lowering, increasing hypoglycemia risk.
Chemotherapy Drugs: Potential alteration of effectiveness for certain treatments.
Acid-Reducing Medications: Curcumin may increase stomach acid.
Antibiotics: Possible altered absorption or effects.
Antidepressants: Caution advised, though more research is needed.
Hormone-Sensitive Drugs: Caution due to weak estrogen-like effects.
Immunosuppressants: Possible interaction with drugs like tacrolimus.

Conclusion

While culinary turmeric is safe for most, high-dose supplements require careful consideration. Individuals with gallbladder issues, bleeding disorders, iron deficiency, or a history of kidney stones should be cautious. Pregnant and breastfeeding women and those facing surgery should avoid medicinal doses. Always consult a healthcare provider before starting new supplements, especially with underlying conditions or prescription medications.

Authoritative Link

For more information on the potential for iron deficiency anemia due to high-dose turmeric, see the article published in Cureus.

Frequently Asked Questions

Yes, for most individuals with pre-existing conditions, consuming turmeric in the small amounts typically used in cooking is considered safe. The primary risks are associated with the high concentrations of curcumin found in supplements, not the moderate intake from dietary sources.

Turmeric can make conditions like gallstones and bile duct obstructions worse because high doses can cause the gallbladder to contract and increase bile production.

Health experts recommend discontinuing turmeric supplements at least two weeks before any scheduled surgery due to its blood-thinning effects, which could increase the risk of bleeding.

No, it is not recommended to take turmeric supplements if you have iron deficiency or anemia, especially in conjunction with iron supplements. Curcumin can interfere with the body's ability to absorb iron.

While rare, liver damage from turmeric supplements can present with symptoms such as jaundice (yellowing of the skin or eyes), unusual tiredness, dark urine, and stomach pain.

Yes, turmeric can lower blood sugar levels, and when taken with antidiabetic drugs, it may cause blood sugar to drop too low, leading to hypoglycemia. Blood sugar should be monitored closely.

The amount considered safe can vary based on individual health and the form of turmeric. Always discuss your specific needs and potential interactions with a healthcare provider, especially when considering supplements.