Drs. David Welsh, Robert Siggins, and Chris Taylor have received a new R01 to identify personalized approaches to overcoming inconsistent responses to microbiota-targeted geroprotection and validate the capacity of these precision medicine strategies to offset mechanisms of biological aging in persons with HIV (PWH) that consume alcohol. The investigators will test two Generally Recognized As Safe (GRAS) treatments, a Lactobacillus reuteri probiotic and a blueberry-based antioxidant mix, and their interactions with well-characterized human hosts to inform machine learning (ML) enabled predictive algorithms and to identify mechanisms contributing to treatment-specific effects. This work is based on the hypothesis that an individual’s characteristics predict probiotic and blueberry supplement capacities to reduce senescent CD8+ T cells in PWH that use alcohol. The results from these studies will provide [a] proof of concept of precision medicine geroprotective / senoprotective strategies, [b] mechanistic insights as to the impact of probiotic and antioxidant foods on aging mechanisms, and [c] a roadmap to optimize other treatments to maintain healthspan in aging PWH that use alcohol.