In genetically heterogeneous male UM-HET3 mice, dietary supplementation with astaxanthin at an average concentration of 1840 ppm, initiated at 12 months of age, is associated with a 12% increase in median lifespan (p = 0.003), while meclizine at an average concentration of 544 ppm is associated with an 8% increase in median lifespan (p = 0.03), with no significant effect observed in females despite similar dosing.

In male mice, two different compounds reduce cellular damage by either blocking a growth signal called mTORC1 or boosting the body's natural defense system against oxidative stress. This reduces damage to cells and mitochondria, slows aging, and extends lifespan. Female mice do not experience the same effect because they have lower levels of the compounds in their blood, so the protective pathways are not activated strongly enough.