All of those sources give you energy. However, I would argue that dairy can provide the most benefit to the digestive system due to good bacteria present. But if you are lactose intolerant this wouldn’t be great for you. And if you are gluten intolerant grains wouldnt be good for you. Proteins don’t necessarily cause disturbances but don’t provide gut health benefits. Fruits are primarily sugars. So this question is not that great.
