. . . . "The findings, he says, build on previous research he is done on IGF-I, including a study that looked at a group of Ecuadorians who had low levels of cancer and diabetes due to a genetic mutation that lowered levels of IGF-I. In the new study, Longo and his colleagues found that high-protein foods derived from plants, such as beans and nuts, did not have the same effect on mortality as did high-prot" .