The present invention discloses herein a synergistic composition(s) of bioactive agents for optimizing cellular health. Particularly, a synergistic bioactive composition for optimizing cellular health, wherein the composition comprising therapeutic blend of betaine of thiol histidine and sirtuin activator(s) or salts thereof present in the ratio of 1:0.5 to 1:90, along with pharmaceutically acceptable excipients. In another embodiment, the invention discloses novel synergistic nutritional composition comprising synergistic combination of bioactives L-ergothioneine and nicotinamide mononucleotide chloride present in the ratio ranges from 1:1 to 1:80. The present invention provides promising and effective nutritional composition for improving cellular health by regulating expression of transcriptional factor, pro-inflammatory cytokines, and reducing cell apoptosis, ROS level and DNA damage in the cell.
