Let's say you're 65; there's Alzheimer's in your family, so you've likely inherited a gene or two that tips your scale arm a bit; you've been burning the candle at both ends for years; you love bacon; and you don't run unless someone's chasing you.
Digamos que tienen 65 años; corre el alzhéimer en su familia, probablemente heredaron un gen que eleva un lado de tu balanza un poco, se han desvelado mucho durante los años; les encanta la tocineta; y solo corren si los persiguen.