Sometimes, it's pretty bad. Regardless, my personal goal is to BE healthy and avoid drugs, surgery, and radiation as much as I can. I follow the 80-20 Rule: eat healthy 80% of the time, but build in 20% for moderate indulgences. Research confirms that extremely rigid diets fail more often than balanced and flexible approaches to eating.
I am, however, rigid on one thing: No high fructose corn syrup, sodas, or artificially flavored drinks. Living this way doesn't make me immune to anything, but I think I have the strength and stamina to bounce back more quickly than I would if I was eating junk food and treating my body poorly.
Here's something that happened recently. One Tuesday morning I awoke feeling just fine. About thirty minutes later I had a pain - actually two pains. One was in my back and the other was low and in the front. I stayed home hoping it would get better with rest. It didn't and I called my wife to come home and take me to the hospital. That pain was so bad that I was actually shaking.