[You] and only one You
“We are survival machines – robot vehicles blindly programmed to preserve the selfish molecules known as genes. This is a truth which still fills me with astonishment.”
― Richard Dawkins, The Selfish Gene
Yes, the foods we eat can trigger which genetic programming gets switched on and off -- it's cause and effect. The same for exercising our bodies. But the most powerful way might just be the way we think, how we think and the quality of those thoughts which will cause a change in our brains and will therefore change what we are.