Food and health
Harry J Flint, Sylvia H Duncan and Wendy R Russell
Sir: why do my parents always tell me I need to eat more fruit and vegetables instead of pasta and pizza?
Food provides the energy and nutrients needed for growth and health, but poor dietary choices can also harm our wellbeing. In addition to energy, a balanced intake of vitamins, minerals, essential amino acids, and healthy fats is crucial. Most food is digested in the stomach and small intestine and absorbed into the bloodstream; however, plant fibre cannot be digested this way. Instead, it reaches the large intestine, where it feeds the gut microbiome. These microbes ferment fibre, producing short-chain fatty acids that provide extra energy and releasing beneficial phytochemicals. Through these processes, the microbiome strongly influences metabolism and immune function. Diets rich in fibre from cereals, fruits, and vegetables—often reflected in a wide range of colours—help maintain a healthy microbial balance and support overall health.