"Everything we’ve been told about food and exercise for the past 30 years is wrong," says Fed Up, a new film urging viewers to take action against what former FDA commissioner David Kessler calls "the great public health epidemics of our time." In other words? The American diet.

Everything Americans throw into their baskets and trolleys as they peruse the aisles of their local supermarket has built an industry that's worth over $600 billion. But who actually heads out to pick up the groceries and when they do it is changing. How are big chains and local mini-marts adapting?

Digital is transforming how we eat. Anyone with a kitchen and a camera can take a picture, upload it and watch it spread in seconds. With millions of recipes and thousands of bloggers, nutritionists, and chefs at our fingertips, how is 'always on' information shaping our diet?

When people are scanning the aisles of a supermarket, it's not just taste that influences their buying decisions. A number of extrinsic factors – from the brand to the label – have a significant impact as well. But a study has found that GMO labels don't put people off buying products.