Description 

Colocasia esculenta (L.) Schott is a perennial, herbaceous plant belonging to the Araceae (arum) family. It is a robust, acaulescent (stemless) herb that typically grows to a height of 0.8 to 2 meters. The plant produces a swollen, starchy underground stem known as a corm, which is the primary edible part. The corm is tuberous, measuring 3–5 cm or more (up to 15 cm) in diameter, and may produce stolons (horizontal runners) and lateral cormels (eddoe-type smaller corms) depending on the variety.

The leaves are large, simple, and broadly ovate to heart-shaped (cordate) in outline, measuring 13–45 cm in length and 10–35 cm in width. A distinctive feature is that the leaf stalk (petiole) attaches to the underside of the leaf blade (peltate), rather than at the notch of the lobed base, which distinguishes it from similar-looking plants like Xanthosoma. The leaves are held pendently from long, erect petioles that can reach 25–80 cm or more in length, with a sheath extending 1/3 to 2/3 of their length. The leaf blade has a waxy, glaucous upper surface that sheds water, forming “mercury droplets” on its surface. Leaf colors vary from light green to dark purple, depending on the cultivar.

The flowers are rarely produced in many cultivated varieties, but when present, the inflorescence consists of a yellow to orange spathe (bract) measuring 20–30 cm long, surrounding a central spadix . The plant is native to Southeast Asia (from India to Southern China and Sumatra) and is now widely cultivated and naturalized throughout tropical and subtropical regions worldwide, including Africa, the Pacific Islands, the Caribbean, and South America. Nigeria is one of the world’s top producers of taro.

Common names

It is widely referred to as cocoyam in Nigerian English, especially in southern and eastern regions, where it is a common root crop alongside yams and cassava. Note that “cocoyam” sometimes broadly includes related species like Xanthosoma sagittifolium (new cocoyam), but C. esculenta is the “old cocoyam.”

  • English: Taro, Dasheen, Eddoe, Cocoyam, Elephant ears (ornamental), Old cocoyam
  • French: Taro, Songe, Madère, Chou-chine, Dachine
  • Spanish: Malanga, Papa, Papachina, Rascadera, Yota
  • Portuguese: Colcas, Alcolcas, Inhame da Africa, Inhame do Egipto
  • Swahili: Mjembe, Mjimbi, Myugwa
  • Chinese: 紫芋 (Zǐ yù – purple taro)
  • Nigerian Names:
    • Yoruba: Koko, Isu koko (cocoyam)
    • Igbo: Ede (general term for cocoyam/taro)
    • Hausa: Gwazar tuwo (sometimes used; cocoyam is less common in the north)
    • Pidgin/Broad Nigerian: Cocoyam, Taro

Health Benefits 

Colocasia esculenta possesses numerous scientifically supported health benefits, largely attributed to its rich content of bioactive compounds, including polyphenols, flavonoids, dietary fiber, and essential micronutrients. The corms and leaves are nutrient-dense. The corms provide complex carbohydrates (mainly starch with resistant starch), dietary fibre, potassium, magnesium, phosphorus, manganese, and modest amounts of protein, vitamin C, vitamin B6, and vitamin E. Leaves are richer in protein, fibre, vitamins A and C, folate, calcium, iron, and antioxidants (polyphenols, flavonoids). Potential benefits include: 

  • Hepatoprotective (Liver-Protecting) Effects: A 2025 study published in Animal Models and Experimental Medicine investigated the methanolic extract of taro flowers and demonstrated significant hepatoprotective activity in animal models. The extract dose-dependently mitigated CCl₄-induced acute liver injury by reducing liver enzymes (ALT, AST, ALP, bilirubin, creatinine), normalizing lipid profiles (reducing cholesterol, triglycerides, LDL while increasing HDL), and boosting antioxidant enzymes (catalase). Histopathological analysis confirmed reduced hepatocellular necrosis and vascular congestion. In silico studies showed promising binding affinity with inflammatory markers TNF-α and IL-6.
  • Antioxidant Activity: Taro leaves and flowers are rich in polyphenols and flavonoids, which exhibit potent antioxidant properties. The methanolic extract of taro flowers demonstrated moderate ABTS and DPPH free radical scavenging activity with IC₅₀ values of 117.18 and 160.41 μg/mL, respectively. The leaves contain chlorophyll, carotenoids, and anthocyanins, with total carotenoids ranging from 1.20–1.95 mg/100g and lutein content as high as 5222 μg/100g—higher than spinach.
  • Anti-inflammatory Activity: A 2025 review in the Journal of Experimental Pharmacology highlights the anti-inflammatory potential of C. esculenta root extract. Studies have shown that the extract effectively inhibits carrageenan-induced rat paw edema and reduces the production of inflammatory mediators such as nitric oxide (NO), PGE₂, and cytokines (COX-2 and iNOS expression) in LPS-treated cells.
  • Anticancer Potential: Research has indicated that methanolic extracts from taro corms and leaves possess intriguing anti-tumor activity against gastric adenocarcinoma cells. The whole phytocomplex of Colocasia demonstrates potential anticancer properties. The high content of bioactive compounds with antioxidative potential contributes to cancer-preventive effects.
  • Antidiabetic and Metabolic Benefits: Taro leaves possess antidiabetic properties, and the high dietary fiber content aids in blood sugar regulation. The leaves also exhibit hypolipidemic (cholesterol-lowering) effects, which are beneficial for metabolic health.
  • Nutritional Value: Taro leaves are low in calories but rich in protein (approximately 30.7 g/100g dry weight), dietary fiber, and micronutrients. They provide essential amino acids including threonine, valine, leucine, isoleucine, phenylalanine, and lysine. The leaves are excellent sources of calcium, iron, phosphorus, zinc, and B-complex vitamins. The corms contain fine-grained, easily digestible starch and are good sources of potassium.
  • Digestive and gut health: High fibre and resistant starch support regular bowel movement, feed beneficial gut bacteria, and may aid blood sugar control through a medium glycaemic index. 
  • Heart health and blood pressure: Potassium helps regulate blood pressure; antioxidants and fibre may reduce cholesterol and oxidative stress. 
  • Other Pharmacological Activities: Additional reported activities include antimicrobial (antibacterial, antifungal, anthelmintic), anti-urolithiatic (kidney stone-preventing), wound healing, antihypertensive, and neuropharmacological effects.
  • Other: Traditional uses for diabetes management, wound healing, and general nutrition; leaves may help with anaemia prevention and eye health due to vitamin A. Many benefits are supported by nutritional profiles and preclinical research, though strong clinical evidence for specific therapeutic claims varies. In Nigerian diets, it contributes to energy and micronutrient intake.

Other benefits 

Culturally, cocoyam features in Nigerian soups (e.g., ofe ede), festivals, and traditional meals, providing caloric diversity alongside yams and cassava. It generates employment across cultivation, processing, and marketing chains and has export potential in processed forms (flour, chips).

  • Staple Food Crop: Taro is a fundamental staple food for millions of people in Africa, Southeast Asia, the Pacific Islands, and the Caribbean. Nigeria is one of the world’s top producers of taro. It tolerates wet soils and partial shade, making it suitable for intercropping or marginal lands.
  • Culinary Uses:
    • Corms: The starchy corms are boiled, steamed, baked, or fried. They are used to prepare various traditional dishes, including poi (Hawaii), fufu (West Africa), and curries (South Asia).
    • Leaves: The young leaves are cooked as a vegetable similar to spinach. They are used in traditional recipes such as Patra (India—gram flour-coated leaves rolled and steamed), Kalalou (West Africa—leaf soup), and Palusami (Pacific Islands—baked with coconut cream).
    • Flowers: The flowers are also edible and are used in some regional cuisines.
  • Ornamental Plant: Due to its large, dramatic, heart-shaped leaves, Colocasia esculenta is widely grown as an ornamental plant, often referred to as “elephant ears.” Purple-leaved cultivars (var. purpurea) are particularly popular.
  • Agricultural Uses: The leaves and stems, as well as processing by-products, are used as animal feed and green manure.
  • Environmental Uses: The plant has environmental applications, including use in erosion control and wetland management.
  • Traditional Medicine: Taro has been used in folk medicine for various conditions, including arthritis, neurological disorders, respiratory distress, blood purification, and as a general health tonic.
  • Industrial Uses: Corm starch has industrial applications in food processing (thickener, noodles, baked goods), adhesives, paper, and biodegradable materials.

How it is used 

  • As Food (Culinary):
    • Boiled/Steamed Taro Root: Corms must be peeled and thoroughly cooked (boiled, roasted, fried, pounded into fufu, or dried into flour for thickening soups or making swallow). In Nigeria, common preparations include boiled/pounded cocoyam, added to soups (e.g., Igbo ofe ede with leaves or corms), or made into chips.
    • Taro Chips: Thinly sliced taro root is deep-fried or baked as a crunchy snack.
    • Taro Leaves (Cooked): Fresh leaves are boiled for at least 45 minutes to an hour (often with coconut milk, palm oil, onions, fish, or meat) to destroy calcium oxalate crystals. The resulting sauce is rich and nutritious.
    • Thickener in Soups: Commonly used as a thickening agent in traditional soups such as ofe oha and ofe onugbu.
    • Fermented Products: Taro corms are fermented to produce traditional dishes in various cultures (e.g., poi in Hawaii).
  • As Medicine (Traditional and Emerging Applications):
  • Extracts: Methanolic extracts of taro flowers have been studied for hepatoprotective effects in animal models.
  • Leaf Preparations: Traditional preparations of taro leaves are used for wound healing, anti-inflammatory purposes, and as a general health tonic.
  • Leaf Juice: Leaf juice or decoctions appear in remedies for stomatitis, haemorrhoids, or inflammation in some West African traditions. 
  • Other Uses: Ornamental landscaping, animal feed, and as a starch source for industrial applications.

Preparation examples: Peel corms, cut into pieces, and boil or roast until soft (cooking neutralises irritants). For leaves — wash, chop, and cook thoroughly (boil or steam with other vegetables). For flour — peel, slice, dry, and mill corms. Always cook well; raw parts are acrid. Traditional processing (peeling, boiling, pounding) improves safety and palatability.

Side Effects/Caution 

Properly peeled and thoroughly cooked Colocasia esculenta corms and leaves are generally safe as food.

  • Acridity and Calcium Oxalate Crystals: Raw taro contains needle-like calcium oxalate crystals (raphides) that can cause immediate burning pain, intense itching, and swelling of the lips, mouth, tongue, and throat if chewed or eaten raw . This can lead to copious salivation and difficulty in breathing, swallowing, or speaking. Intense gastric irritation may also occur if swallowed.
  • Proper Cooking is Essential: Thorough cooking (boiling, steaming, baking) for at least 45 minutes denatures the calcium oxalate crystals and eliminates acridity, making taro safe for consumption . Never consume raw or undercooked taro.
  • Seek Urgent Medical Attention: If swelling of the lips or tongue occurs, or if there is difficulty breathing or swallowing after contact with raw taro, seek immediate medical attention.
  • Antinutritional Factors: In addition to oxalates, taro contains tannins and phytates, which can interfere with mineral absorption. However, cooking and processing techniques (soaking, boiling, fermentation) significantly reduce these antinutritional factors and improve nutrient bioavailability.
  • Allergic Reactions: As with any food, rare allergic reactions may occur in sensitive individuals. Symptoms may include itching, hives, or gastrointestinal distress.
  • Pregnancy and Breastfeeding: The cooked tuber and leaves are widely consumed as food during pregnancy in many cultures without reported issues. However, medicinal doses or concentrated extracts should be used only under the guidance of a qualified healthcare professional.
  • Toxicity in Animal Studies: While acute toxicity studies show no abnormal clinical symptoms at certain doses, sub-acute studies of some extracts have demonstrated dose-dependent toxic effects. Standardized dosages and safety profiles require further clinical validation.

References

  1. “Colocasia esculenta (L.) Schott.” Plants of the World Online, Royal Botanic Gardens Kew, powo.science.kew.org/taxon/urn:lsid:ipni.org:names:1170772-2. Accessed 16 Apr. 2026.
  2. “Colocasia esculenta (PROTA).” PlantUse, plantuse.plantnet.org/en/Colocasia_esculenta_(PROTA). Accessed 16 Apr. 2026.
  3. “Colocasia esculenta.” ScienceDirect, Elsevier, www.sciencedirect.com/topics/agricultural-and-biological-sciences/colocasia. Accessed 16 Apr. 2026.
  4. “Taro (Colocasia).” Queensland Poisons Information Centre, 23 Mar. 2023, www.poisonsinfo.health.qld.gov.au/plants-and-mushrooms/taro-colocasia.
  5. “Taro.” IPFS, ipfs.io/ipfs/bafybeiemxf5abjwjbikoz4mc3a3dla6ual3jsgpdr4cjr3oz3evfyavhwq/wiki/Kolokassi.html. Accessed 16 Apr. 2026.
  6. “Colocasia esculenta.” Missouri Botanical Garden Plant Finder, www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=276338. Accessed 16 Apr. 2026. 
  7. “Colocasia esculenta – Uses, Side Effects, and More.” WebMD, www.webmd.com/vitamins/ai/ingredientmono- [relevant entry if available]. Accessed 16 Apr. 2026. 
  8. “Colocasia esculenta (L.) Schott.” Plants of the World Online, Royal Botanic Gardens, Kew, powo.science.kew.org/taxon/urn:lsid:ipni.org:names:30000000-2. Accessed 16 Apr. 2026. 
  9. Bradbury, J. H., and W. D. Holloway. Chemistry of Tropical Root Crops: Significance for Nutrition and Agriculture in the Pacific. Australian Centre for International Agricultural Research, 1988.
  10. FAO. Roots, Tubers, Plantains and Bananas in Human Nutrition. Food and Agriculture Organization of the United Nations, 1990.
  11. Lebot, Vincent. Tropical Root and Tuber Crops: Cassava, Sweet Potato, Yams and Aroids. CABI Publishing, 2009.
  12. Mitharwal, S., et al. “Nutritional, Phytochemical Composition and Potential Health Benefits of Colocasia esculenta Leaves: A Review.” Food Chemistry, 2022. 
  13. Mitharwal, Swati, et al. “Nutritional, Phytochemical Composition and Potential Health Benefits of Taro (Colocasia esculenta L.) Leaves: A Review.” Food Chemistry, vol. 383, 30 July 2022, p. 132406. ScienceDirect, doi:10.1016/j.foodchem.2022.132406.
  14. Mohammad, Mahathir, et al. “A Hepatoprotective Experiment on Taro Vegetable (Colocasia esculenta (L.) Schott) Flower Employing Animal Models by Mitigating Oxidative Stress.” Animal Models and Experimental Medicine, vol. 8, no. 7, 2025, pp. 1166-1185. HEP Journals, doi:10.1002/ame2.70031.
  15. Onwueme, I. C. The Tropical Tuber Crops: Yams, Cassava, Sweet Potato and Cocoyams. Wiley, 1978.
  16. Pereira, Priscilla R., et al. “Anticancer and Immunomodulatory Benefits of Taro (Colocasia esculenta).” International Journal of Molecular Sciences, vol. 22, no. 1, 2021, p. 265. 
  17. Pertiwi, Reza, et al. “Colocasia Esculenta as a Potential Plant-Based Medicine: A Review on Its Bioactive Constituents and Pharmacological Activities.” Journal of Experimental Pharmacology, vol. 17, 2025, pp. 755-803. Semantic Scholar, doi:10.2147/JEP.S382567.
  18. USDA. “Taro, Raw.” FoodData Central, United States Department of Agriculture, 2019.