It is like a new model car, you can drive it into the ground in 5 years if you put a lot of miles on it. You can do the same to your body. I am sure this guy had a lot of fun miles on his big road trip. I guess smoking would be like using the wrong fuel or not changing the oil on top of the wear and tear from the hard miles.
Remember, the average life expectancy in the US is 76.1 years for men. So, it isn't even a given we will make it to 66. Living a full life to 80 is not as common as it may seem ...
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