Educational information, not medical advice — ask your doctor or midwife.
Butterwort is a small wild plant that traps and eats insects. Its pale leaves lie flat like a star. They feel greasy and sticky, which is how the plant got its name.
It grows in wet, poor ground. You find it in bogs, flushes and damp hills across northern Europe. Irish and Scottish Gaelic speakers knew it well, as leith uisce and mòthan.
Folk healers put the leaves on sore skin and gave leaf tea for coughs. Dairy folk used the leaves to thicken fresh milk.
Here is the verdict up front. There are no human trials of butterwort for any health use. Long traditional use is not proof that it works, and it is not proof that it is safe.
No one has shown how butterwort acts in the human body.
In lab dishes, extracts of the leaves slow the growth of some bacteria and fungi. That is a dish, not a person. Whether it does anything on your skin or in your chest has not been tested.
The milk trick is better understood. The leaves carry enzymes that cut up milk protein. They also carry souring bacteria.
Together these thicken fresh milk into a ropy drink. That is a change in the food, not a health effect in you.
The sticky leaf also holds mucilage, a slimy plant gum. Gums of this kind can coat and soothe raw skin. Butterwort itself has not been tested that way in people.
Butterwort is rare on shop shelves. It is not a standard supplement.
Forms you may meet:
- Fresh leaves, crushed and laid on skin in old folk practice. - Dried leaf, brewed as a tea. - Tincture, an alcohol extract, sold by a few herb suppliers.
- A named ingredient in some old European cough syrups. - Live plants sold for windowsills and terrariums. These are sold as houseplants, not as food.
Supply is unreliable and quality is rarely tested. Wild picking is restricted or banned in many places.
Butterwort held a strong place in Gaelic folk life. In Scotland it was mòthan, a charm plant more than a medicine.
Records such as the Carmina Gadelica describe it being carried for protection. People used it in charms over cattle, over milk and in love rites. Milk from a cow that had eaten it was thought to guard the household.
In Ireland it was known as leith uisce. Folk accounts mention the leaves being used on chapped hands, cuts and sore cows' udders.
In Nordic dairy work the leaves were stirred into fresh milk to make a thick, ropy soured drink. This food use is well recorded.
Some European folk sources also list leaf tea for coughs, including whooping cough. These are historical accounts. They describe what people did, not what a reader should do.
Stop using it and see a doctor if any of these happen:
- A rash spreads, blisters, or the skin turns hot and red. - You wheeze, your lips or face swell, or you feel faint. Call emergency services for these. - A cough lasts more than three weeks, or you cough up blood. - You run a fever, or a wound oozes pus. - You get bad vomiting or diarrhoea after milk made with the leaves.
Tell the doctor exactly what you took and how you used it.
Butterwort is not an approved medicine in the UK, the EU or the US, and it is not a common supplement. Wild plants are protected in several European countries, and in Britain it is an offence to uproot any wild plant without the landowner's permission.
Evidence grades and traditional-use labels are explained in our methodology. Nothing here is medical advice.
What it is typically used for, usual dose, cautions, and the study behind it where real trial data exists.
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