Michael Mosley and his team of doctors return to tackle more questions about our health and well-being. This series finds out why we all need a little bit of sunshine, the truth about super foods and if caffeine really makes you more alert. It searches for answers to questions like is sugar as toxic as tobacco? Can we cheat our way to a healthy diet by preparing food differently? Are e-cigarettes safe? Do computer screens harm our eyes? By experimenting on their own bodies and visiting some of the world's leading research hospitals, this team of doctors gathers the evidence to provide answers to the medical questions we face everyday.