AbstractObjectiveTo explore the terms on which nutrition should engage with the global challenges ahead.DesignAnalysis of current orientation of nutrition and policy.ResultNutrition faces four conceptual problems. The first is that nutrition has fissured into two broad but divergent directions. One is biologically reductionist, now to the genome; the other sees nutrition as located in social processes, now also requiring an understanding of the physical environment. As a result, nutrition means different things to different people. The second problem is a misunderstanding of the relationship between evidence, policy and practice, assuming that policy is informed by evidence, when there is much evidence to the contrary. The third problem is that nutrition is generally blind to the environment despite the geo-spatial crisis over food supply, which will determine who eats what, when and how. How can we ask people to eat fish when fish stocks are collapsing, or to eat wisely if water shortage dominates or climate change weakens food security? The fourth problem is that, in today's consumerist and supermarketised world, excess choice plus information overload may be nutrition's problem, not solution.ConclusionNutrition science needs to re-engage with society and the environment. The alternative is, at best, to produce an individualised approach to public health or, at worst, to produce brilliant science but be policy-irrelevant.