Corn Silk
Zea mays
The silky threads of the corn plant, used in traditional Chinese medicine since at least 1476 to increase urination and reduce swelling. Lab and animal studies suggest it may affect blood sugar, blood fats and blood pressure.
Safety at a glance
- PregnancyNothing recorded
- BreastfeedingNothing recorded
- MedicinesNothing recorded
- Who should avoid itNothing recorded
- AllergiesNothing recorded
- ToxicityNothing recorded
Tap a box to read the safety notes below. “Nothing recorded” means our sources don't cover it, not that it's safe.
What is Corn Silk?
- Plant family
- Poaceae, the grass family
- Parts used
- The silky threads (stigmas) of the corn ear, usually dried and made into tea
- Genus
- Zea
- Species
- mays
Also called
Maize Silk, Stigma Maydis
Traditionally used for
- Fluid retention (traditional)
- Increasing urination (traditional)
- Diabetes (traditional)
Traditionally described as
- May increase urination (traditional)
- Antioxidant (in lab studies)
Health topics
Where Corn Silk appears in symptom search, and why. Being listed doesn't mean it's a proven treatment.
- High Blood Pressure
Limited, low-quality trials suggest corn silk tea may add to the effect of blood pressure medicine.
- High Cholesterol
A review of 4 trials suggests corn silk decoction may improve blood fats; most trials weren't blinded.
Traditions that use it
- Traditional Chinese Medicine
Recorded since 1476 and listed in the Chinese Pharmacopoeia; used to increase urination and reduce swelling.
How it's prepared
Common ways Corn Silk is prepared or sold. This isn't advice on how to take it; see Safety below.
- Decoction
Corn silk has also been taken as a decoction (simmered in water).[1]Review or trial
- Tea / Infusion
In Chinese trials, corn silk was taken as a tea.[2]Review or trial
What does the research say?
Traditional use
These are traditional uses, not proven treatments.
In China, corn silk was first recorded in the Southern Yunnan Materia Medica in 1476, and it's listed in the Chinese Pharmacopoeia. In traditional Chinese medicine it's used to increase urination and reduce swelling, and it has been used for diabetes, diabetic kidney disease, high blood fats and high uric acid. It's also added to foods and health products.[3]Study
Laboratory & animal research
Lab and animal results show what might be worth studying in people. They don't show that the herb has these effects in humans.
In lab and animal studies, corn silk extracts have lowered blood fats, blood pressure and blood sugar, may help reduce inflammation, and have shown antioxidant activity. They also stopped the growth of some bacteria and the yeast Candida. Corn silk is described as a potentially safe herb, but these effects haven't been confirmed in people.[3]Study
In lab studies, compounds from corn silk, such as quercetin, rutin and apigenin, killed or slowed the growth of cervical, breast, pancreatic and colon cancer cells. In animal studies, its antioxidants reduced kidney damage caused by some chemotherapy drugs. This hasn't been tested in people with cancer.[4]Study
A 2025 review looked at corn silk's possible role in diseases linked to ageing, such as Alzheimer's and Parkinson's disease, heart and blood vessel disease, diabetes, obesity and kidney problems. In lab and animal studies its compounds acted as antioxidants and may help reduce inflammation, both thought to drive ageing.[5]Study
Research in people
The same review says early trials in people, mostly on diabetes, look promising, but larger, well-designed trials are needed to show whether corn silk is safe and works.[5]Study
A 2019 review of 5 Chinese trials with 567 people with high blood pressure found that adding corn silk tea to blood pressure medicine may lower blood pressure more than the medicine alone. Most trials were of poor quality, so the evidence is limited.[2]Review or trial
Technical detail: blood-pressure lowering response RR 1.27 (95% CI 1.17 to 1.38).
A 2019 review of 4 trials in people with angina found that corn silk decoction, often alongside usual treatment, may lower total and LDL ("bad") cholesterol and triglycerides and raise HDL ("good") cholesterol. Most trials weren't blinded, which may have exaggerated the effects.[1]Review or trial
In short
Not well tested in people.
Sources
- [1] Corn silk decoction for blood lipid in patients with angina pectoris: A systematic review and meta-analysis · DOI: 10.1002/ptr.6474Review or clinical trial
- [2] Corn Silk Tea for Hypertension: A Systematic Review and Meta-Analysis of Randomized Controlled Trials · DOI: 10.1155/2019/2915498Review or clinical trial
- [3] An Umbrella Insight into the Phytochemistry Features and Biological Activities of Corn Silk: A Narrative Review · DOI: 10.3390/molecules29040891Peer-reviewed study
- [4] Anti-cancerous effect of corn silk: a critical review on its mechanism of action and safety evaluation · DOI: 10.1007/s13205-023-03673-1Peer-reviewed study
- [5] Unlocking Corn Silk's Potential: Bioactive Compounds Targeting Age-Related Diseases · DOI: 10.1002/mnfr.70117Peer-reviewed study
This information is educational and traditional in nature, and is not a substitute for professional medical advice. Unfamiliar word? See what these words mean.