Rice is a cereal grain which is the seed of species of grass, and grows best in river valleys and moist climates. After sugarcane and maize, it is the third highest in terms of world production, and for more than half of the global population is the staple food most widely consumed, especially in Asia, providing more than 20% of global calorie consumption.
Genetic and archaeobotanical evidence shows that rice was domesticated in river valleys in China as much as 13,500 years ago, spreading throughout Asia and thence to Europe, finally reaching the Americas via European colonisation.
There are numerous varieties of rice and many regional cuisines prepare it differently, with emphasis in recent years moving away from the more refined, polished rice to the whole grain, brown and wild varieties, which are nutritionally more valuable. It is a good source of protein, vitamins including K, B5 (pantothenic acid) and B3 (niacin), the antioxidant vitamin E, and minerals including manganese, selenium, phosphorus and zinc.
Whole grain rice is also a good source of fibre, and can have a beneficial effect on reducing cholesterol and improving heart health, while the rarer red and black grained varieties are particularly rich in antioxidants.