Banana

The banana is a giant herb, not a woody tree: its ‘trunk’ is actually a pseudostem formed by overlapping leaf sheaths, reaching 2–8 m tall depending on the cultivar. The crown consists of large entire leaves that split along the veins, with long sheaths clasping the pseudostem. The inflorescence arises at the growing tip; female flowers lower down develop into fruits arranged in hands along a bunch, ending in the purple male bud. After fruiting, the pseudostem dies back and is replaced by suckers from the underground rhizome, so the clump is perennial.

The edible banana (Musa × paradisiaca) is a hybrid of M. acuminata and M. balbisiana domesticated in Southeast Asia; according to POWO, M. balbisiana is naturally distributed across tropical and subtropical Asia. Bananas are now grown throughout the tropics and subtropics, from backyard gardens and lowland plots to intensive plantations. Vietnam lies within the centre of diversity and grows many cultivars, including dessert Cavendish (AAA), AAB cooking/plantain types and the small, fragrant ‘chuối ngự’.

A medium banana (about 118 g) provides roughly 105–110 kcal, 22–27 g carbohydrate, 3 g fibre, about 422–450 mg potassium, about 0.43 mg vitamin B6 (about 25–33% of the recommended daily allowance), about 10.3 mg vitamin C, plus magnesium, manganese and folate. Green bananas are rich in resistant starch, which acts as a prebiotic and gradually turns into sugars (glucose, fructose, sucrose) as the fruit ripens — which is why ripe bananas taste sweet and have a higher glycaemic index. The peel contains dopamine and other catecholamines with antioxidant activity, while the pulp provides serotonin derived from the amino acid tryptophan.

Bananas are among the world's most important staple fruits, eaten fresh, dried, fried, baked or processed into flour. A 2019 systematic review (Falcomer et al., Nutrire) concluded that green banana — as flour, cooked or whole — improves digestion, blunts the glycaemic response and supports gut health through resistant starch. A 2026 study indexed on ScienceDirect recorded a vitamin B6 content of about 4.35–5.09 mg/100 g in banana fruit, confirming its nutritional value. The Harvard T.H. Chan School of Public Health lists bananas among potassium- and fibre-rich foods that benefit blood pressure and heart health, while advising portion control because of their natural sugar content.

Bananas are a safe food and allergy is rare; people with advanced kidney disease should limit intake because of the high potassium content, and people with diabetes should watch the portion of ripe fruit. For conservation, the cultivated banana is not separately assessed by the IUCN; however, production relies mostly on vegetative propagation, leaving a genetically uniform crop vulnerable to diseases such as Panama wilt (Fusarium oxysporum TR4), while many wild Musa species that carry valuable genes are threatened in the wild.