1. Sustainable diets : welcome to the arguments 2. Methodologies : measuring what matters while not drowning in complexity 3. Health : nutrition science and the messy effects of diet on health 4. Environment : why food drives ecosystems stress 5. Culture and society : the social conditions shaping eating patterns 6. Food quality : everyone likes their own food 7. Real food economics : runaway costs and concentration 8. Policy and governance : will anyone unlock the consumption lock-in? 9. Conclusions : why sustainable diets matter now.