 The proposed study is an extension study to two ongoing double blind, randomized, placebo-controlled studies evaluating the effect of gender-specific nutritional supplementation on growth of short and lean adolescent boys and girls. The aim of the current study is to extend these short term double blind, randomized, placebo controlled studies one in boys and one in girls and to add an extension study, which will evaluate the long term effect of the gender specific nutritional supplementation on final height. Patients completing the ongoing studies will be offered to continue treatment with the study formula until final height. Patients reluctant to continue to consume the study formula will be offered to continue followup only during the extension study without any intervention. 