The obesity pandemic is an increasing burden for society. Information on key drivers of the nutrition cycle of (a) social causation, (b) biological causation and (c) health selection is vital for effective policies targeted at the reduction of obesity prevalence. However, empirical causal knowledge on (a) the social predictors of diet quality, (b) its impact on corpulence and (c) the socioeconomic consequences of obesity is sparse. We overcome the limitations of previous research and acquire comprehensive causal insight into this cycle.

Therefore, we analyse two German socio-epidemiological panel surveys exploiting their longitudinal panel structure utilising hybrid panel regression models.

General population of Germany.

German Health Interview and Examination Survey for Children and Adolescents (KiGGS, n 17 640; age 0–24 years) and the German National Nutrition Monitoring (NEMONIT, n 2610; age 15–82 years).

The results indicate that (a) interestingly only sex, education and age explain healthy diets; (b) increases in a newly developed Optimised Healthy Eating Index (O-HEI-NVSII) and in nuts intake reduce BMI, while growing overall energy intake, lemonade, beer and meat (products) intake drive corpulence; (c) in turn, developing obesity decreases socioeconomic status.

These results suggest that policies targeted at the reduction of obesity prevalence may be well advised to focus on boys and men, people with low education, the promotion of a healthy diet and nuts intake, and the limitation of lemonade, beer and meat (products) intake. Therefore, future research may focus on the replication of our findings utilising longer panels and experimental approaches.