Parsley (Petroselinum crispum): Uses, Evidence and Safety
Parsley (Petroselinum crispum): a food herb with mostly lab and animal research, plus cautions on the essential oil, warfarin and vitamin K, oxalate, pregnancy and allergy.
Content last updated . This page has not been medically reviewed.
Safety first. Natural products can cause side effects and interact with medicines. Read herb safety and interactions before you use anything on this page.
Safety first. Parsley sprigs on a plate are a food. The sources we read raise three points for other uses. (1) The US LactMed database says the essential oil should not be used because of the potential toxicity of its apiol and myristicin content. [1] (2) People taking warfarin are advised to keep vitamin K intake consistent, so ask the prescriber or clinic how herbs count. [2] (3) Adverse reactions to parsley are mainly allergic, including cross-reactions with carrot, celery and fennel. [1] If someone has swallowed parsley oil or a concentrated product, call Poison Help at 1-800-222-1222 (US); for a severe allergic reaction, call 911.
What parsley is
Parsley is Petroselinum crispum (Mill.) Fuss, accepted by GBIF in the family Apiaceae (the carrot and celery family). [3] LactMed lists it under the older name Carum petroselinum and says the leaf, seed and root contain the volatile oils apiol and myristicin. [1] The leaf is the culinary part. This page gives no foraging or plant-identification help; for wild plants, see Plant and Mushroom Poisoning.Traditional use
This is tradition, not proof. A 2024 review says parsley is traditionally used as a diuretic, as a liver and stomach tonic, and for urinary stones and indigestion. [4] LactMed notes that warm compresses or poultices of parsley have been used for breast engorgement and sore breasts, that capsules of sage and parsley are said to decrease milk flow, and that some mothers in Türkiye reportedly use parsley to increase milk supply; it says no scientifically valid clinical trials support the milk uses. [1] The sources do not name particular peoples, so we do not.What research shows
The same 2024 review concludes that parsley has shown several activities in preclinical studies, with a big lack of clinical evidence. [4]| Use | What the source found | Strength of evidence | Population and form studied |
|---|---|---|---|
| Liver, kidney, stone, nerve, heart and cancer protection | Effects reported in animal and cell-based studies. [4] | Preclinical (cells or animals) | Extracts in animals and cells |
| Kidney health | A 2024 review reports that animal studies showed benefits, while limited human studies revealed modest improvements in urinary composition and kidney markers. [5] | Insufficient evidence in people | Mixed; mostly animal studies |
| Dissolving kidney stones | In a laboratory study, parsley and ammi extracts reduced the size of calcium oxalate stones. [6] | Preclinical; no human evidence | Extracts and stones, not people |
| Antioxidant enzymes and oxidative stress markers | In a small randomized crossover trial, two red blood cell enzyme activities rose during a week with parsley added to a controlled diet, while two others did not change. [7] | Insufficient evidence (biomarkers, not health outcomes) | 14 healthy adults, 7 men and 7 women; parsley as food, 1999 |
| Parsley tea for any condition | Proper evidence not found in the sources we read. | Marketing claim | None identified |
A result for an extract in animals does not transfer to eating parsley, and neither transfers to tea or to concentrated products. We searched PubMed (2026-10-23) for parsley with randomized, review and trial terms and found no larger human trial of a health outcome.
Medicines: warfarin and vitamin K
MedlinePlus says some foods and drinks that contain vitamin K can affect how warfarin works, and advises eating consistent amounts of vitamin K-containing food from week to week and talking to the doctor before diet changes. [2] We found no source we could read that gives parsley's vitamin K content, so we do not state one. For anyone on warfarin the practical point is consistency and asking the prescriber or anticoagulant clinic how culinary herbs fit. See Vitamins and Blood Thinners, Herbs and Blood Thinners and How Interactions Work. The 2024 kidney review also says herb-drug interactions with parsley at high doses need investigation. [5]Kidney stones and oxalate
A 1980 laboratory paper that measured oxalate in common foods found high levels in spinach, rhubarb, peanuts, chocolate, parsley and tea. [8] Oxalate is part of the chemistry of calcium oxalate stones. Whether parsley matters for a particular person who forms stones is a question for their clinician; the sources we read do not answer it. See Herbs and Kidney Disease.Pregnancy and breastfeeding
LactMed says parsley is "generally recognized as safe" as a food by the US FDA, that there are no data on parsley components in breastmilk or on its safety in nursing mothers or infants, and that the essential oil should not be used. [1] The 2024 kidney review lists safety during pregnancy among the questions needing investigation, particularly at high doses. [5] The sources we read do not describe food-amount risks in pregnancy. See Pregnancy and Breastfeeding.Other safety points
- Allergy: adverse reactions are primarily allergic, with cross-reactions to other Apiaceae such as carrot, celery and fennel. [1] See Herbal Allergy and Cross-Reactivity.
- Children, older adults, liver disease, surgery: not described in the sources we read.
- Quality: see Quality Testing and Certifications for how to read supplement labels. We give no amounts to take.
Frequently asked questions
Does parsley have health benefits?
It is a food herb, and the research on health effects is mostly in animals and cells. A review found a big lack of clinical evidence. [4]
Is parsley tea good for kidneys?
Proper evidence not found. Human studies of parsley for kidney health are limited and modest. [5]
Can I eat parsley on warfarin?
Ask the prescriber or clinic. The general advice is to keep vitamin K intake consistent from week to week. [2]
Is parsley safe in pregnancy?
Food use is described as generally recognized as safe by the FDA; high-dose safety in pregnancy needs investigation, and the essential oil should not be used. [1][5]
Can parsley cause an allergic reaction?
Yes, mainly in people allergic to related plants such as carrot, celery and fennel. [1]
References
- US National Library of Medicine, LactMed, Parsley (record NBK501880, read through its PubMed entry). Read 2026-10-23.
- US National Library of Medicine, MedlinePlus, Warfarin. Read 2026-10-23.
- GBIF Backbone Taxonomy, Petroselinum crispum match record. Read 2026-10-23.
- Petroselinum crispum (Mill.) Fuss (Parsley): An Updated Review of the Traditional Uses, Phytochemistry, and Pharmacology. Journal of Agricultural and Food Chemistry, 2024 (abstract read). Read 2026-10-23.
- Renal health benefits and therapeutic effects of parsley (Petroselinum crispum): a review. Frontiers in Medicine, 2024 (abstract read). Read 2026-10-23.
- Pharmaceutical Insights Into Ammi and Parsley: Evaluating Antioxidant Activity, Total Phenolic Content, and Kidney Stone Disintegration Properties. Advances in Pharmacological and Pharmaceutical Sciences, 2025 (abstract read). Read 2026-10-23.
- Effect of parsley (Petroselinum crispum) intake on urinary apigenin excretion, blood antioxidant enzymes and biomarkers for oxidative stress in human subjects. British Journal of Nutrition, 1999 (randomized crossover trial, abstract read). Read 2026-10-23.
- Oxalate content of some common foods: determination by an enzymatic method. Journal of Human Nutrition, 1980 (abstract read). Read 2026-10-23.