(CNRS) What if social behavior affected the progression of even noncontagious diseases? This is precisely what has been demonstrated by French CNRS teams, with support from IRD, CEA, Paris-Sud and Montpellier universities, and colleagues from Spain and Australia. Using a fly model of intestinal cancer, the researchers have shown that disease progression is impacted both by social isolation — which has a negative effect — and the composition of the social group with which individuals associate.