Job's Tears (Coix lacryma-jobi)

Job's tears (Coix lacryma-jobi) contains coixol and other bioactive compounds that demonstrate anti-cancer properties through inhibition of COX-2 expression and tumor cell proliferation. The seed extract has been developed into Kanglaite®, an approved injectable treatment for lung, breast, and liver cancers in China.

Origin & History

Job's Tears (Coix lacryma-jobi) is a grain crop native to Asia, with the cultivated variety (var. ma-yuen) widely used in traditional medicine systems. The ingredient is derived from the seeds, typically processed through solvent extraction (methanol or hexane) or consumed as whole seeds, dehulled flour, or bran.

Historical & Cultural Context

Job's Tears has centuries of use in Traditional Chinese Medicine for treating pulmonary edema, wet pleurisy, and chronic gastrointestinal diseases, considered sweet in taste and cold in nature. In Ayurvedic, Siddha, and Unani-Tibb systems, the leaves are used as tea for diabetes and rheumatism, while roots are decocted for dysentery and menstrual problems.

Health Benefits

• Anti-cancer activity: Kanglaite®, an injectable lipid extract, has been approved by Chinese Ministry of Public Health for treating lung, breast, and liver cancer (preclinical evidence)
• Anti-proliferative effects: Extracts suppress preneoplastic lesions and COX-2 protein expression in colon tumors (in vitro studies)
• Metabolic support: Consumption improves lipid metabolism and reduces liver fat accumulation (preliminary evidence)
• Antioxidant properties: Demonstrates free radical scavenging and lipid peroxidation inhibition (in vitro evidence)
• Antimicrobial activity: Contains compounds effective against bacteria, yeasts, and fungi (laboratory studies)

How It Works

Job's tears extract exerts anti-cancer effects primarily through suppression of cyclooxygenase-2 (COX-2) protein expression, which reduces inflammatory mediators that promote tumor development. The bioactive compounds, including coixol and coix seed oil, inhibit cellular proliferation pathways and induce apoptosis in cancer cells. These mechanisms help prevent progression of preneoplastic lesions to malignant tumors.

Scientific Research

While the research dossier lacks specific human RCTs with PMIDs, preclinical evidence exists for Job's Tears extracts, particularly Kanglaite® which inhibited tumor growth in mice transplanted with HepG2 hepatocellular carcinoma cells. In vitro studies tested 330 extracts from different cultivars on human colon adenocarcinoma cells (HT-29) for anti-proliferative activity.

Clinical Summary

Preclinical studies demonstrate that Job's tears extract suppresses preneoplastic lesions and reduces COX-2 expression in colon tumor models. The most significant clinical development is Kanglaite®, an injectable lipid extract approved by China's Ministry of Public Health for treating lung, breast, and liver cancers. However, most evidence comes from preclinical research and Chinese clinical studies, with limited large-scale randomized controlled trials in Western populations. Additional human studies are needed to fully establish therapeutic efficacy and optimal dosing protocols.

Nutritional Profile

Job's Tears is a nutrient-dense grain with the following approximate composition per 100g dry weight: Protein: 13–18g (notably high for a cereal grain; contains essential amino acids including leucine ~1.2g, lysine ~0.5g, and glutamic acid as the dominant amino acid ~2.8g); Total Carbohydrates: 60–70g (primarily starch, with a relatively low glycemic index compared to refined grains); Dietary Fiber: 3–6g (mix of soluble and insoluble fiber, including beta-glucans which contribute to cholesterol-lowering effects); Total Fat: 5–9g (higher fat content than most cereals; rich in unsaturated fatty acids — oleic acid ~35–40% of total fatty acids, linoleic acid ~40–45% of total fatty acids, and palmitic acid ~15–18%); Moisture: ~11–13g when dried. Key Micronutrients: Calcium: ~20–30mg; Iron: ~3–6mg (bioavailability moderate, enhanced by vitamin C co-consumption); Magnesium: ~70–110mg; Phosphorus: ~200–240mg; Zinc: ~1.5–2.5mg; Potassium: ~200–280mg; B Vitamins: Thiamine (B1): ~0.28–0.35mg; Riboflavin (B2): ~0.15–0.19mg; Niacin (B3): ~1.5–2.5mg; Vitamin E (tocopherols): ~0.5–1.0mg. Bioactive Compounds: Coixenolide (a lipid ester mixture, primary active component in Kanglaite®, concentrated in the seed oil at ~5–8% of oil weight); Coixol (6-methoxybenzoxazolinone): a benzoxazinone derivative with muscle-relaxant and anti-inflammatory properties, present at trace levels (~0.1–0.5mg/100g); Polysaccharides (coixan A, B, C): present at ~1–3% of dry weight, demonstrated hypoglycemic activity in animal models; Phytosterols: beta-sitosterol and stigmasterol (~50–100mg/100g total), contributing to lipid-lowering effects; Ferulic acid and other phenolic acids: ~200–500mg/100g (antioxidant capacity); Glycerides: mono- and diacylglycerols structurally similar to those found in olive oil. Bioavailability Notes: The protein digestibility-corrected amino acid score (PDCAAS) is moderate (~0.5–0.7); soaking or sprouting improves mineral bioavailability by reducing phytate content (phytic acid present at ~0.5–1.2g/100g in whole grain form); fat-soluble bioactive compounds (coixenolide, phytosterols) show enhanced absorption when consumed with dietary fat; traditional preparation by boiling into porridge increases starch gelatinization and may improve overall digestibility.

Preparation & Dosage

The research does not provide specific clinically studied dosage ranges or standardized extract concentrations. Traditional use involves consumption as whole seeds in porridge, rice, and pasta preparations, while Kanglaite® is administered as an injectable extract. Consult a healthcare provider before starting any new supplement.

Synergy & Pairings

Green tea extract, turmeric, reishi mushroom, milk thistle, astragalus

Safety & Interactions

Job's tears is generally considered safe when consumed as a food grain, with centuries of traditional use in Asian cuisines. However, safety data for concentrated extracts or injectable forms like Kanglaite® is limited in Western literature. Potential interactions with chemotherapy drugs or blood thinners have not been thoroughly studied. Pregnant and breastfeeding women should avoid therapeutic doses due to insufficient safety data, though dietary consumption appears safe.