Protein powder is being added to foods from bread to ice-cream, as it makes you feel fuller for longer. But do we really need more protein in our diets?
Luisa Dillner: There may be a difference between a food's listed calorific value, and the amount of calories it actually delivers – but only a small one
Rhiannon Lucy Cosslett: I'm all for Oliver's anti-obesity crusading, but his remarks about bad food and big TVs do reveal a lack of understanding of modern poverty
Research suggests that sugar and fat may be addictive – but the findings are controversial. Which foods do you find hardest to resist, and have you experienced withdrawal symptoms?