I discovered this forum a couple months ago while looking for peoples' experiences using Niagen, Elysium Health's Basis, Nicotinamide Riboside, and Pterostilbene. The information was very helpful. I am collaborating with a project manager from Harvard Medical School and some engineers to develop a new system to measure functional aging biomarkers and estimate functional age. The head of a major Harvard lab encouraged us to do that project. The system will be used to validate whether people are functioning physically at a younger age after receiving biochemical or genetic aging interventions or using the aforementioned supplements.
Below is a link that has an overview of the status of the aforementioned supplements and well as the research that led to them and details on the development of the functional age test. Although this page is on a crowdfunding platform for strictly approved scientific research, you are certainly free to use it as a source of useful details and links to other information without considering the fundraising aspect: