Running on a Treadmill vs. Running Outdoors

Is it better to run on a treadmill or outdoors? Apparently, the differences are not only personal preferences but health advantages as well. For one, running outdoors can burn additional fat than running on a treadmill. This is because running outside takes more energy because of wind resistance versus the energy taken indoors when there is a lack of resistance. On the other hand, running on a treadmill might be safer in terms in of decreasing the potentiality of being involved in a hazardous accident as opposed of running outside where the risk of danger slightly increases. Additionally, running on a treadmill might place a strain on the joints than running outside due to a fixated time of being placed in the same location doing repetitive activities.