Food provides the nutrients we need for effective metabolic functioning. Malnutrition in all its forms is common across the globe and causes many serious health issues from conception and throughout the life course. Some 800 million people still go to bed hungry today, while around 2 billion people are now overweight or obese these include poor people and increasingly citizens of low and middle income countries – and their numbers are growing. Overlapping with these numbers around 2 billion people suffer from micronutrient deficiencies, which cause physical and cognitive problems. Poor diets rich in processed foods and animal products and low in fruit and vegetables are now the main cause of premature deaths worldwide, implicated in diseases such as obesity, strokes, diabetes, cardiovascular disease and some cancers. In addition, our nutrition and broader health status also influence our susceptibility to infectious diseases. Diet-related health outcomes are shaped by multiple social, economic, cultural and political factors and these influences on food consumption interact with other factors (from environmental through to genetic) to influence health.