<p>Sustainably meeting the food demands of a growing population based on finite resources while protecting the environment is one of the great challenges of humanity in the coming decades. This dissertation combines three essays that examine how future patterns of global food consumption will affect human health, and how the food system changes driven by the ongoing global nutrition transition will affect the environment. The production of food needed to meet a growing population combined with changes in food consumption patterns are placing unprecedented levels of stress on the planet’s scarce natural resources. In this context, while the existing literature has mainly focused on increasing production, the magnitude of loss and waste is too large to be ignored. The first essay contributes to the literature by examining the linkages between consumers’ food waste at the national level on the one hand, and global food security and environmental health on the other hand. Absent significant behavioral changes or successful policy interventions, food waste will nearly double by 2050. Emerging economies are likely to play a key role in driving this growth in global food waste. Further findings indicate that the global benefits of food waste mitigation are greatly enhanced in the context of a more open international trade regime. Yet even as food loss and waste has been undernutrition and overweight/obesity levels have also been increasing. Together, these trends form a triple challenge for food security, global sustainability and human health. In the second essay I examine the role of the excessive calorie availability as an historical driver of adult BMI. I find that, in part driven by excess in calorie availability, individuals in more recent cohorts are overweight or obese earlier and for larger proportions of their lifespan than those in earlier cohorts. This highlights the potential for unintended health consequences of agricultural and trade policies directed at increasing calorie supplies. In the third essay I introduce a novel framework that extends the UN-FAO’s methodology for assessing undernutrition to also assess the extent of overconsumption and obesity. This framework allows for examination of the dynamics of the double burden of malnutrition between 2015 and 2050. Specifically, this framework shows how shifting towards healthier and more sustainable food consumption levels and reducing food waste could synergistically address multiple health and environmental burdens. </p>