I found reading this article fascinating (and a little horrific). If there is any stronger argument against not maintaining a healthy diet that excludes processed foods, I am yet to find it.
Eating sensibly and with intelligence is the cornerstone to a healthy lifestyle for the long-term. Exercising, getting enough sleep and drinking the required amount of water every day all help, but if what we put into our bodies in terms of sustenance is not chosen wisely then the struggle will always be uphill.
Read and see what you think of Dr Chris Van Tulleken's experience and let me know your thoughts.