Helioseismology, the study of solar vibrations, has revealed a higher degree of homogeneity in the sun than is commonly assumed. This is contrary to the standard solar model (SSM), in which the sun is assumed to be segregated into a core region and radiative and convective regions which do not experience significant mixing with the core. Furthermore, a degree of solar homogeneity and concomitant mixing implies a lower core temperature than is typically assumed, which in turn means that significant helium production may not be occurring in the sun. Deuterium produced via hydrogen fusion therefore may not be consumed in producing helium. The deuterium abundance of the interstellar medium appears to be consistent with the possibility that deuterium is not consumed in the sun via helium production, but escapes into interplanetary space due to the sun's homogeneity.