4.7 years. Also, no evidence that it reduces the risk of getting it, the benefit is purely delayed onset. Still, I'd take an extra 5 years of working brain, if

4.7 years. Also, no evidence that it reduces the risk of getting it, the benefit is purely delayed onset. Still, I'd take an extra 5 years of working brain, if only I could learn a second language (does Python count?). https://pmc.ncbi.nlm.nih.gov/articles/PMC7089902/ https://pmc.ncbi.nlm.nih.gov/articles/PMC7089902/