Educational information, not medical advice — ask your doctor or midwife.
Capuchina, also called mastuerzo, is the garden nasturtium (Tropaeolum majus). People eat the round leaves, the bright orange flowers and the green seed pods. All three taste sharp and peppery, a lot like watercress.
It is used both as a food and as a home remedy. In Latin American folk medicine it was given for coughs, colds, bladder trouble, wounds and hair loss. Traditional use is not proof that a remedy works, and it is not proof that it is safe.
Here is the short verdict on the evidence. Human research is thin, and almost all of it tested nasturtium mixed with horseradish root, not nasturtium alone. That mix looks promising for some infections, but the proof is not firm.
As a salad green, capuchina is an ordinary food for most adults. As a strong tea, tincture or capsule it is a different matter. The plant's mustard oils can irritate the gut, the kidneys and the skin.
The proposed action comes from mustard oils, the same family of compounds found in horseradish and watercress.
When you chew or crush the leaf, an enzyme turns a stored compound into benzyl isothiocyanate. This is the hot, biting taste. The same reaction happens when the fresh herb is cut for a tea.
In test tubes, benzyl isothiocyanate slows the growth of several bacteria and some fungi. It has also shown anti-inflammatory activity in cell and animal work. Whether any of this happens inside the human body at food or tea amounts is not established.
One idea is that these oils pass into the urine after you absorb them. That would put them in contact with the bladder lining. This route is suggested by lab and animal data, not proven in people.
The leaf also carries vitamin C. Vitamin C prevents and treats scurvy, and that effect is well proven in people. Eating the fresh leaves was once a real way to avoid scurvy on long voyages.
The traditional hair rinse is often explained by better blood flow in the scalp. That explanation has not been tested in a proper human trial.
Capuchina is sold and used in several forms. The fresh plant is the most common one in Latin America.
- Fresh leaves and flowers, eaten raw in salads. - Pickled seed pods, used like capers. - Fresh juice from the crushed leaves.
- Tea or infusion made from fresh or dried herb. - Tincture, an alcohol extract. - Tablets or capsules, usually combined with horseradish root.
- Hair rinses and scalp lotions. - Crushed-leaf poultices for the skin.
The tablets used in European research are a fixed mix of nasturtium herb and horseradish root. Products sold as nasturtium alone have not been tested the same way. Strength is rarely standardised, so two brands can differ a lot.
Capuchina comes from the Andes, in what is now Peru and Bolivia. Local people grew it as a food long before Europeans arrived.
Spanish travellers took the plant to Europe in the sixteenth century. European herbals soon listed it for scurvy and for chest complaints. Sailors and gardeners ate the leaves as a fresh green.
In Latin American home medicine it was brewed as a tea for coughs and colds. The juice was dropped on wounds and sores. Rinses made from the leaves were rubbed into the scalp against hair loss.
In twentieth-century Germany the herb entered licensed medicine. It was paired with horseradish root and sold for urine and airway infections. German herbal authorities also recorded who should not take it.
These records describe what people did in the past. They are not a recommendation for you to treat yourself.
Stop using capuchina and see a doctor if any of these happen.
- Fever, chills, or pain in your back or side. - Blood in your urine. - Burning urine that is no better after two days. - Vomiting, or stomach pain that keeps up. - A rash that spreads after you use it on the skin.
Get emergency help for swelling of the lips, tongue or throat, or for trouble breathing. These can be signs of a severe allergic reaction.
Tell your doctor you have been taking it. Herbs count as part of your treatment.
In the United States, capuchina is an ordinary food plant and may be sold as a dietary supplement. It is not approved there to treat any disease.
In Germany, nasturtium herb with horseradish root is licensed as a herbal medicine. In most of Latin America and the European Union it is sold as food or as a traditional herbal product.
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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