How does Horsetail work?

The chemicals in horsetail may have antioxidant and anti-inflammatory effects. Plants related to horsetail contain chemicals that work like "water pills" (diuretics) and increase urine output. But it isn't clear whether horsetail has this effect.

Are there safety concerns?

Horsetail might not be safe. It contains a chemical called thiaminase that breaks down the vitamin thiamine. Some products are labeled "thiaminase-free," but there's not enough information available to know if these products are safe.

Do not take horsetail if:
  • You are pregnant or breast-feeding.
  • You have thiamine deficiency.
  • You have diabetes.
  • You have heart problems.
  • You have kidney problems.

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