It's nice to find an easy, real answer that's as close as our next meal in a world where trying to be happy often leads us down the rabbit hole of self-help books and health trends. Think about what would happen if the key to a better mood and a more positive view on life was hidden in our fruit bowls. That being said, new study shows that this might not be so far from the truth, especially when it comes to vitamin C-rich foods like kiwifruit and regular vitamin C pills.