Educational information, not medical advice — ask your doctor or midwife.
Sheep's sorrel is a small wild plant with sour, arrow-shaped leaves. Botanists call it Rumex acetosella. In German it is Kleiner Sauerampfer, the little sorrel.
It grows on poor, acid soil across Europe, Asia and North America. Young leaves are eaten raw in salads and soups. European folk healers also made the leaf into teas, gargles and poultices.
Here is the honest verdict. There are no good human trials on sheep's sorrel. Long folk use is not proof that it works, and it is not proof that it is safe.
The plant is best known today as one herb in Essiac tea. That blend has been sold for cancer since the 1920s. Reviews of it have not found a benefit, and the page below says so plainly.
No one has shown what sheep's sorrel does inside the human body. What follows is lab and animal work, not proof in people.
The sour taste comes from oxalic acid and its salts, called oxalates. Oxalate binds calcium. In large amounts it can form sharp crystals in the kidneys.
Like other dock plants, the leaf holds small amounts of anthraquinones. In animals, these push the bowel to move. The amount here is low, and the effect in people has not been measured.
Tannins give the leaf a drying, puckering feel on the tongue. The old use as a gargle rested on that feel.
Flavonoids in the leaf act as antioxidants in test tubes. Whether that changes anything in a person is unknown.
In lab dishes, strong extracts slow the growth of some bacteria. Those tests use concentrated extracts on cells. They do not tell you what a cup of tea does.
You will meet sheep's sorrel in a few forms:
- Fresh young leaves, picked wild or grown, eaten in salads and soups. - Dried cut leaf, brewed as a tea. - Liquid extract or tincture in alcohol.
- Capsules or powder of the dried herb. - Herbal blends, mainly Essiac and Flor-Essence, where it is mixed with burdock root, slippery elm and Indian rhubarb. - Rarely, creams and salves for the skin.
Quality control is loose. Labels may not say how much leaf is in each dose. Some blends list the herbs but not the amounts.
European country people treated sheep's sorrel as both food and medicine. The sour leaf was a spring green after a long winter.
Herbals from the 16th century onward listed it for fevers and thirst. Writers described it as cooling. It was also used as a gargle for a sore mouth and as a poultice on sores.
Sailors and farm families ate sour greens to ward off scurvy. Fresh sorrel does carry vitamin C, so that use had a real basis.
In the 1920s a Canadian nurse, Rene Caisse, sold a four-herb tea called Essiac. Sheep's sorrel was one of the four. She said the recipe came from an Ojibwa healer.
Essiac spread widely as a folk cancer tea through the 20th century. It was never approved as a cancer treatment. This page records that history; it does not recommend copying it.
Stop taking it and see a doctor the same day if you notice:
- Sharp pain in your back or side - Blood in your urine, or passing much less urine than usual - Repeated vomiting, or severe belly pain - Numbness or tingling in your hands, feet or face - Marked weakness, or an irregular heartbeat - A spreading rash, or swelling of the lips or throat
Go to an emergency department if you have trouble breathing, or if you cannot keep fluids down.
Tell your doctor or pharmacist that you took sheep's sorrel. Bring the packet with you.
In the United States, sheep's sorrel is an ordinary food plant and may be sold as a dietary supplement. In the UK, EU and Canada it is sold as a food or food supplement, not as a licensed medicine. No country has approved it, or Essiac tea, to treat any disease.
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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