Yi Yi Ren (Semen Coicis or Coix Seed)

What Is Yi Yi Ren

Yi Yi Ren commonly known as Semen Coicis or Coix Seed is the mature seed of Coix lacryma-jobi L., which is a perennial herb belonging to the family Poaceae. It is a relatively practical and common Chinese herbal medicine, which first appeared in <Shennong Ben Cao Jing> in the late Western Han Dynasty (around 100 BCE).

There are three species of this genus, namely Coix aquatica Roxb., Coix lacryma-jobi L., and Coix gasteenii B.K.Simon. Among them, the most famous species is Coix lacryma-jobi L..

Coix lacryma-jobi L. is also known as Job’s tears or Adlay and is a food crop. They often grow on warm and humid roadsides and valley streams below 2000 meters above sea level. They are native to Southeast Asia and are now widely grown in tropical and subtropical regions of the world. Their seeds are medicinal and edible, and their stalks can be made into animal feed.

Coix lacryma-jobi L.

In the autumn, people harvest the mature fruits of Coix lacryma-jobi L., pat them, take out their seeds, dry them in the sun, remove their husks, seed coats, and impurities, and use them directly, or stir-fry them, make them into Chinese herbal medicines.

Yi Yi Ren contains monoglycerides, triglycerides, myristic acid, palmitic acid, azelaic acid, stearic acid, linoleic acid, coix polysaccharide A-C, fructo-oligosaccharide, glucosan 1~7, acid polysaccharide CA-1, acid polysaccharide CA-2, p-hydroxybenzoic acid, vanillic acid, syringic acid, ferulic acid, p-coumaric acid, caffeic acid, sinapic acid, 2-hydroxyphenylacetic acid, coixol, syringaresinol, catechin, sitosterol, campesterol, ergosterol, cholesterol, stigmasterol, quercetin, kaempferol, rutin, friedelin, cylindrin, lactamases, alkaloid, indenes, purines, lignans, protein, amino acids, starch, dietary fiber, vitamins, and minerals.

Generally, white and plump Yi Yi Ren with high starch content and a slight smell is preferred.

According to <Compendium of Materia Medica>, the medicinal nature of Yi Yi Ren is relatively cool, with a sweet and bland taste. It has a certain therapeutic effect on the pathological changes of the spleen, stomach, and lung meridians.

In traditional Chinese medicine, it is often used to increase secretion of urine and remove dampness, invigorate the spleen and stop diarrhea, expel pus, remove toxins and disintegrate masses, and treat dysuria, edema, beriberi, diarrhea due to spleen deficiency, acute bronchitis, hypertension, hyperlipidemia, fatty liver, spasms of limbs, atrophic arthritis, gout, lung abscess, acute appendicitis, ulcerative colitis, chronic superficial gastritis, vascular dementia, pelvic inflammation, dysmenorrhea, endometritis, salpingitis, synovitis of ischiac tubercle, infectious soft wart, flat wart, eczema, esophageal cancer, gastric cancer, rectal cancer, and other malignant tumors.

There are about 200 kinds of traditional Chinese medicine prescriptions containing it, such as Si Miao Wan, Bao Ji Wan, and Shen Qi Bai Zhu Wan.


  • Anti-inflammation, inhibiting xylene-induced ear swelling and complete Freund’s adjuvant-induced paw swelling in mice.
  • Raising the pain threshold and inhibiting the pain caused by the hot plate experiment and glacial acetic acid experiment in mice
  • Anti-oxidation, scavenging DPPH free radicals, hydroxyl free radicals, and superoxide anion free radicals.
  • Increasing insulin levels and reducing blood glucose levels in hyperglycemic mice induced by alloxan or epinephrine.
  • Reducing plasma total cholesterol, triglyceride, low-density lipoprotein, and very low-density lipoprotein-cholesterol in hyperlipidemic rats.
  • Increasing secretion of urine, treating edema, abdominal distension, and dysuria caused by damp preponderance due to spleen deficiency.
  • Removing spleen dampness, invigorating the spleen, and treating diarrhea caused by excessive dampness due to spleen deficiency.
  • Relaxing muscles and tendons, treating spasms of limbs and limb pain caused by dampness.
  • Treating numbness of the foot, weakness and swelling of the foot, and flaccidity syndrome due to dampness-heat.
  • Clearing heat and promoting diuresis, treating headache, aversion to cold, chest tightness, and heaviness sensation of body and limbs caused by damp-warm diseases in the early stage, or summer-heat and damp in the qifen.
  • Clearing heat in the lung and intestine, expelling pus, treating lung abscess, and acute appendicitis.
  • Removing toxins and disintegrating masses, treating warts and cancerous swelling.
  • Inhibiting the proliferation of cervical cancer U14 cells, cervical cancer HeLa cells, colon cancer SW480 cells, breast cancer MCF-7 cells, lung cancer A549 cells, and leukemia HL-60 cells.
  • Its polysaccharides can increase the spleen index and thymus index of mice, enhance the phagocytic ability of macrophages and lymphocyte proliferation, and improve immunity.
  • Its sterols can induce ovulation in female golden hamsters and stimulate the growth of their ovarian follicles.
  • Studies have found that its aqueous extract has certain embryotoxicity and can accelerate uterine contractions in pregnant rats.


Side Effects

  • At present, there is no literature report that Yi Yi Ren has toxic effects, and no data is showing that taking it at the prescribed dose can cause serious adverse reactions.

Precautions and Warnings

  • The dosage of Yi Yi Ren should be controlled at 9-30g.
  • It can be made into decoctions, pills, or powders.
  • People allergic to Yi Yi Ren should not take it.
  • Patients with deficiency of body fluid should not take it.
  • Patients with prolapse due to qi deficiency should not take it.
  • Pregnant women should not take it.
  • Breastfeeding women should take it under medical supervision.
  • The unprocessed Yi Yi Ren is recommended for clearing damp-heat, and stir-fry Yi Yi Ren is recommended for invigorating the spleen and stopping diarrhea