Compositions for addressing one or more of the effects of aging are described. The compositions comprise a first component comprising repair system activator(s) such as nicotinamide adenine dinucleotide (NAD+), nicotinamide mononucleotide (NMN), nicotinamide riboside (NR), nicotinic acid adenine mononucleotide (NaMN), nicotinic acid adenine dinucleotide (NaAD), nicotinic acid riboside (NAR), 1-methylnicotinamide (MNM), cyclic adenosine monophosphate (cAMP) and combinations thereof； a second component comprising methyl donor(s) such as S-5′-adenosyl-L-methionine (SAM), methionine, betaine, choline, folate, vitamin B12, or combinations thereof； and a third component comprising antioxidant defense activators such as H2O2, N2S, NaSH, Na2S, and several others, including combinations thereof. Methods of administering the disclosed compositions or separate formulations of repair system activator, methyl donors, and antioxidant defense activators are also disclosed.
