Why teaching kids self-control could leave them healthier later 5 Jan, 2021 11:08 PM 3 minutes to read Training our children to have self-control could set them up to be healthier - and biologically younger - when they reach middle age. Photo / 123RF Training our children to have self-control could set them up to be healthier - and biologically younger - when they reach middle age. Photo / 123RF NZ Herald Training children to have self-control could set them up to be healthier - and biologically younger - when they reach middle age. That's according to new research that drew on data tracking 1000 people from birth to age 45, as part of New Zealand's world-famous Dunedin Study.