I'm not sure about your question but I suppose obesity caused by the easy livin' in the Shire might have caused some decrease in life expectancy
But Hobbits due have a longer lifespan than normal humans yet aren't they meant to be basically the same. Do you think this is because Hobbits avoided the curse of Eru that he put on mankind at the beginning of their existence(gee all this stuff I've learnt just from reading a little bit of Morgoth's Ring
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