For optimum health, eat at the same time every day, advises cancer reseracher and author of A Short Guide to a Long Life, David B. Agus. 'The body likes a strict routine. Eat erratically and get up at inconsistent times, day in and day out, and you will negatively affect hormone levels,' he advises. 'It's been shown, for example, that constant grazing increases the risk of diabetes. Your body needs to anticipate what's happening to it so that it can be prepared.'