Corn silk

Zea mays · 玉米须

Herbs & Roots. Native American, Latin American & Amazon and Chinese Medicine.

Also called Maize silk, Stigma maydis, Yu mi xu

Pinyin: Yù Mǐ Xū

Spanish: Pelo de elote

Adds to water pill effects

The silky threads from the female corn flower, dried and made into tea to support urination and ease swelling.

Did you know? Each strand of corn silk connects to one kernel, and that kernel forms only if the strand catches a pollen grain.

What it may help, and how strong the proof is

Kidneys, bladder & UTIs. Used for urinary problems and swelling. Human trials are very few, and most support comes from animal and lab studies.
Traditional proof
Liver. Used to support bile flow and gallbladder health, based on tradition and lab work.
Traditional proof
Blood pressure. Some animal and lab studies show lower blood pressure. No good human trials show this.
Traditional proof

Parts of the body

Kidneys & bladder, Liver, Heart & vessels

Traditional use

Native American peoples used corn silk tea for bladder and kidney complaints. In Chinese medicine (yu mi xu), it is used to help urination, reduce swelling, and help with jaundice.

How it is classified

Herbal actions: Diuretic, Cholagogue. Energy: neutral.
Chinese medicine: 玉米须 Drain dampness. Nature: neutral. Flavour: sweet, bland. Enters the Bladder, Liver and Gallbladder channels.

How people take it

Tea is the usual form, made from dried silk steeped in hot water. No standard dose has been set, and human trials are few.

Tea, decoction, tincture and capsule.

Where to get it

Corn silk is a by-product of sweet corn and field corn harvests. It is sold dried as loose silk, tea bags, capsules, and tinctures.

Be careful

Corn silk is generally well tolerated, and serious side effects are rare. It can add to fluid loss from water pills and may lower blood pressure further when combined with blood pressure medicines. Use caution with kidney disease, where fluid balance matters.

Avoid if: kidney disease; low blood pressure; pregnancy.

Mixing with other things

Works well together
Both are used in classic urinary tea blends.
Works well together
Often blended with horsetail and other diuretic herbs for urinary tea.
Works well together
Dandelion leaf and root are common partners in kidney and fluid-balance teas.
Works well together
A common partner in mild urinary diuretic teas.
Use caution
Water pills (furosemide, hydrochlorothiazide)
Corn silk may add to fluid and potassium loss from water pills.
Use caution
Blood pressure medicine (lisinopril, amlodipine, losartan)
It may lower blood pressure more when combined with blood pressure drugs.

Adds up with others that may lower blood pressure: , , , , , , , , , , , , , and 12 more.

The honest take

Corn silk has a long folk record as a diuretic tea, but human evidence is thin. Claims about blood pressure and jaundice rest on animal and lab studies. It is a mild, food-like tea, not a proven remedy for kidney problems.