Ginger

Ginger (Zingiber officinale) is a perennial rhizomatous herb 0.6–1 m tall with lance-shaped leaves 15–30 cm long arranged in two ranks, the leafy pseudostems rising from the rhizome. The branching rhizome has a yellowish-brown skin and pale-yellow flesh and contains aromatic essential oil and the pungent phenolics known as gingerols; fresh ginger is rich in 6-gingerol, which dehydrates to shogaol on drying or cooking, markedly increasing pungency. The plant favours a hot, humid climate of 20–30 °C with 1,500–3,000 mm of rain and loose, well-drained soil, and is propagated mainly from seed rhizomes.

According to Plants of the World Online (Kew), the native range of ginger is East Himalaya to South-Central China, in the seasonally dry tropics; it was then cultivated and spread throughout the tropics and subtropics. India and China are the two largest producers, followed by Nigeria, Indonesia, Thailand, Vietnam and Nepal. Ginger needs a growing season of about 8–10 months and is often rotated to limit rhizome rot.

Characteristic actives include the gingerols (6-, 8- and 10-gingerol) — the main pungent compounds of the fresh rhizome — and shogaols formed on drying or cooking; the essential oil accounts for 1–3% and is rich in zingiberene, ar-curcumene and β-bisabolene, while oleoresin makes up 4–8% of the dried rhizome. Paradols, gingerenone A, phenolic acids and starch are also present. The anti-inflammatory, antioxidant and gastrointestinal actions are attributed to these compounds.

Ginger is a spice and a traditional medicine (Rhizoma Zingiberis) used in Ayurveda, Chinese medicine and Vietnamese practice as a warming digestive and anti-nausea remedy. Clinical evidence is growing: a systematic review of 109 randomised controlled trials by Anh et al. (Nutrients, 2020) reported benefits for nausea (morning sickness, motion sickness, postoperative and chemotherapy-induced) and metabolic support; a meta-analysis by Bartels et al. (Osteoarthritis and Cartilage, 2015) found ginger reduced mild-to-moderate knee pain, and a 12-week double-blind RCT of steamed ginger extract (Baek et al., Food & Function, 2024) improved WOMAC scores over placebo. A meta-analysis by Morvaridzadeh et al. (Cytokine, 2020) reported reductions in the inflammatory markers CRP and TNF-α.

Ginger is generally safe at culinary doses; high intakes (above about 4 g/day) may cause heartburn and dyspepsia and can interact with anticoagulants such as warfarin, so caution is advised before surgery. For conservation, Zingiber officinale is assessed by the IUCN as Data Deficient (DD; Red List species 88308170). As a globally traded crop it faces no extinction risk; landraces and semi-wild genetic resources in its native range (East Himalaya to South-Central China) should be maintained to preserve genetic diversity.