Through theHaber-Boschinvention of fertilizer production, we have increased rates of food production to help feed a growing population. This has led to a livestock revolution, and we are now eatingmany animal products.At the same time we have roughly equal populations of malnourished and obese people. The strong increase in mineral fertilizer use and livestock production is known to cause many negative environmental impacts.Here we show that there is a strong correlation between mineral fertilizer used on a national scale with calorie consumption and with obesity and overweight. While no direct causality should be implied, we derive important insight in the relations between diets, health and the disruption of the nitrogen cycle. An important diverging point between fertilizer use and obesity/overweight rates was identified. Up to national average per capita consumption levels of 3,000kcalthere is an increase in the share of the population that is obese or overweight; after 3,000 kcal, the obese/overweight population levels off. However, the average national fertilizer use continues to increase linearly with kcal consumption beyond 3,000 kcal. This suggests that the availability of N fertilizer enabled a boost to food production to reduce malnourishment in the world, but a major part of this fertilizer enabled a shift towards diets that can affect human health in a negative way and has a cost for society both in health care and in environmental consequences. This study can serve as a foundation for making new connections between how fertilizer use feeds different populations of the world.
