Re-remembering the influence of randomized β-carotene on cognitive decline.

The wave of individuals impacted by dementia continues to rise rapidly as worldwide lifespan increases. Dietary strategies to slow cognitive decline and prolong time to clinical dementia remain understudied, but with potentially powerful public health consequences. Indeed, previously conducted large, randomized, placebo-controlled trials of micronutrients remain an under-leveraged resource to study changes in cognitive performance. As a motivating example, we highlight an ancillary report from the Physicians' Health Study, where subjects randomized to β-carotene (a provitamin A carotenoid) had a more attenuated change in longitudinal global cognitive performance and verbal memory, as compared to subjects randomized to placebo. Despite mechanistic evidence from cell and animal studies supporting a vitamin A-mediated role in the biology associated with cognition, limited follow-up work has been conducted. We argue that dietary factors (including provitamin A) deserve a second look, leveraging multi-omic approaches, to elucidate how they may mitigate cognitive decline and dementia risk.