Vegan, grass-fed, kale salad wrote:
Diet is completely overrated for runners.
The difference in marginal benefit between a 'pretty good' diet and a 'great' diet is pretty f*cking small. Eat as healthy as you can, but also realize a slice of pizza once in a while is not going to make a difference what so ever.
It's not that diet is overrated so much as that most people have really stupid ideas about what constitutes a good/bad diet. You seem to be implying that pizza is a "bad" food, but that it is okay to eat it occasionally anyway. I would argue, rather, that quality pizza is actually really good for you, and that the person who eats it occasionally could be eating a 'great' diet.
Along those lines, my unpopular opinion would be that fat is just fine to eat. Strange that this is still an unpopular opinion, since the "fat is evil" idea was not just debunked, but basically discovered to be downright fraudulent years ago (the government's low-fat recommendations were literally not based on one shred of actual science).