There is strong evidence that aging process is controlled by... all types of parasites. Check wikipedia about them: parasites ensure "biodiversity" on the planet, meaning: any single species must not be able to outnumber all others species. There is even hint in the bible within the story of snake (parasite) who wants humans to eat fruit (sugar), parasites #1 food... Parasites eat our minerals which fight free radicals, esp. they steal silica. It won't be easy battle! However, in 100-200 years, we could begin to reach 400-600 years and later, who knows.
See the population growth in the world over the past few centuries. I can't imagine what it would mean if people (including the third world where the growth is) started living 400 years. From my trading experience, I already think we are in a massive bubble. Somehow things will have to correct/stabilise. (source: https://ourworldindata.org/world-population-growth )