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Radish

Raphanus sativus

Also calledLai fu zi (Chinese, seed) · Raphani semen (seed, pharmaceutical Latin) · Black radish · Rábano negro (Spanish)

In older monographsRaphanus sativus var. niger (black radish)

The common garden radish. Its dried seed, lai fu zi, is a Chinese medicine for food stagnation, bloating and phlegmy cough, and the juice of black radish root is a Mexican household remedy for gallstones. Support comes from animal and laboratory work; the few human studies are small and do not test these traditional uses directly.

What it is used for

  • Black radish root juice is used for gallstones in Mexican traditional medicine. In mice fed a gallstone-inducing diet, six days of the juice cleared cholesterol gallstones and lowered blood cholesterol and triglycerides. There are no human studies.2,3

  • Black radish juice lowered serum cholesterol and triglycerides and raised HDL in mice on a lithogenic diet; not tested in people.2

  • In Chinese medicine the seed is used for food retention with distending pain in the upper abdomen. No controlled trials of the seed alone for indigestion were found.1

  • Lai fu zi is used in Chinese medicine for 'eliminating bloating' and abdominal distension; untested on its own in trials.1

  • Cough
    Traditional

    The seed is used in Chinese medicine for panting and cough with phlegm congestion, as an expectorant and antitussive.1

  • Constipation
    Traditional

    Constipation, diarrhoea and dysentery are among the seed's recorded uses in Chinese clinical practice.1

Safety

Pregnancy
Insufficient data
Breastfeeding
Insufficient data

Side effects

  • In a small 14-day crossover trial in 21 people with metabolic syndrome, Sakurajima radish powder raised systolic blood pressure by about 9–10 mmHg and an oxidative-stress marker compared with usual diet, and did not improve blood-vessel function

Toxicity

Black radish juice showed no signs of acute toxicity in mice at single oral doses up to 5000 mg/kg (lyophilised juice). Medicinal doses of the seed have not been formally safety-tested in people in the sources found.

In the healing traditions

  • Traditional Chinese Medicine

    Lai fu zi (Raphani semen)

    Dried seed used for food dyspeptic retention, epigastric and abdominal distending pain, constipation, diarrhoea and dysentery, panting, and cough with phlegm congestion.

    As reviewed by Gao et al. 2022

  • Mesoamerican

    Rábano negro (black radish)

    In Mexican traditional medicine the juice squeezed from the root is a home remedy for pigment and cholesterol gallstones and to lower blood lipids.

    As reported by Castro-Torres et al. 2012

Active compounds

glucosinolates
main secondary metabolites of seed and root; converted by plant myrosinase or gut bacteria into isothiocyanates, which are anti-inflammatory and antibacterial in lab studies
phenylpropanoid sucrosides, flavone glycosides, alkaloids
other constituent classes reported from the seed

History

Lai fu zi has a long history in Chinese clinical practice for digestive stagnation and phlegm. In Mexico, black radish juice is a household remedy for gallstones, and a 2012 mouse study was designed specifically to test that folk use.

Sources

  1. 1.Gao L et al. Traditional uses, phytochemistry, transformation of ingredients and pharmacology of the dried seeds of Raphanus sativus L. (Raphani Semen), a comprehensive review. J Ethnopharmacol 2022 (abstract)
  2. 2.Castro-Torres IG et al. Antilithiasic and hypolipidaemic effects of Raphanus sativus L. var. niger on mice fed with a lithogenic diet. J Biomed Biotechnol 2012
  3. 3.Jeon H et al. Inhibitory effect of black radish (Raphanus sativus L. var. niger) extracts on lipopolysaccharide-induced inflammatory response in RAW 264.7 cells. Prev Nutr Food Sci 2020 (abstract)
  4. 4.Tokushige A et al. Efficacy and safety of Sakurajima radish in patients with metabolic syndrome: a phase IIb randomized, three-period crossover trial. Nutrients 2026 (abstract)
  5. 5.GBIF Backbone Taxonomy: Raphanus sativus L. (IUCN category via GBIF)

Reference, not prescription. Nothing here is medical advice. Herbs can interact with medicines and be dangerous in pregnancy; tell your doctor or pharmacist about anything you take.