Why causality, and not prediction, should guide obesity prevention policy.

Chiolero A Institute of Primary Health Care (BIHAM), University of Bern, Bern, Switzerland; Institute of Social and Preventive Medicine (IUMSP), University of Lausanne, Lausanne, Switzerland; Department of Epidemiology, Biostatistics, and Occupational Health, McGill University, Montreal, QC, Canada. Electronic address: achiolero@gmail.com.