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Limited evidenceGeneral health

Corn Silk

The silky styles of maize, used traditionally as a soothing diuretic for bladder irritation. Nearly all research is chemical and preclinical, and the few human reports are small and poorly controlled.

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What the science says

  • Bladder and urinary use Limited evidence

    Narrative reviews of corn silk phytochemistry catalogue diuretic and anti-inflammatory activity in animal models, and reviews of urinary botanicals list it as a traditional demulcent for bladder irritation. No randomised controlled trial has tested corn silk for urinary symptoms.

  • Blood glucose Limited evidence

    A small study in human male subjects reported effects of corn silk on glycaemic markers, alongside a larger body of rodent and in-silico work on its flavonoids. The human study was small and published in a low-visibility journal, so it should not be treated as established.

Dosage & safety

Studied doseNo trial-established dose. Traditional preparation is 4–8 g of dried silk as an infusion two to three times daily; capsules typically supply 400–500 mg.
SafetyGenerally regarded as gentle and it has a long history of food-adjacent use. Its diuretic reputation means caution alongside diuretic drugs and in people with heart or kidney failure, and it may add to the effect of blood-pressure and blood-glucose medications. Allergy to maize is a contraindication. Insufficient data in pregnancy.

How to take it

TimingTaken two or three times a day traditionally; skip the evening serving if it wakes you at night.
With food?Either way; it is gentle on the stomach.
Worth knowingCorn silk is a maize product, so skip it entirely if you react to corn.

Interactions

With medications

  • diuretics

    Additive fluid and potassium loss. talk to your doctor before combining

  • blood-pressure medication

    Possible additive lowering of blood pressure, with dizziness on standing. monitor your blood pressure when you start

  • diabetes medication

    May add to the glucose-lowering effect of insulin or oral agents. check your blood glucose more often when you start or stop

  • lithium

    A diuretic effect can raise lithium blood levels. do not combine without lithium level monitoring

With other supplements

  • other diuretic or glucose-lowering supplements

    Additive effects on fluid balance or blood sugar. introduce one at a time so you can tell what is doing what

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does corn silk help bladder irritation?

Corn silk is a traditional soothing diuretic for bladder irritation, but no randomized controlled trial has tested it for urinary symptoms; nearly all research is preclinical. The evidence is limited.

Does corn silk lower blood sugar?

Not established: one small human study reported effects of corn silk on glycaemic markers, alongside rodent work, and it should not be treated as proven. If you take diabetes medication, check your blood glucose more often when you start or stop.

How much corn silk tea per day?

There is no trial-established dose of corn silk. Traditional preparation is 4–8 g of dried silk as an infusion two to three times daily; capsules typically supply 400–500 mg.

Is corn silk safe with blood pressure pills or diuretics?

Corn silk may add to blood-pressure-lowering and diuretic drugs, causing dizziness or potassium loss, so monitor your blood pressure and talk to your doctor. Do not combine it with lithium without level monitoring, and skip it entirely if you react to corn.

Scientific references

Related in General health

Herbal medicines: what the evidence says (335)