Recent research has found that children who attended pre-kindergarten programs in childhood were more likely to be healthy as adults. One intuitive way of improving population health and longevity may therefore be to invest in pre-kindergarten programs. However, much of the research linking pre-kindergarten programs to health is very recent and has not been synthesized. In this paper, I review the mechanisms linking pre-kindergarten programs in childhood to adult longevity, and the experimental evidence backing up these linkages. I conclude with a critical exploration of whether investments in pre-kindergarten programs could also serve as investments in public health.