Advantage of async

public ActionResult GetData1()
{
    var data = FetchData1FromDatabase();
    return Json(data, JsonRequestBehavior.AllowGet);
}

public ActionResult GetData2()
{
    var data = FetchData2FromDatabase();
    return Json(data, JsonRequestBehavior.AllowGet);
}

public ActionResult GetData3()
{
    var data = FetchData3FromDatabase();
    return Json(data, JsonRequestBehavior.AllowGet);
}
private List<MyData> FetchDataFromDatabase()
{
    using (var db = new MyDbContext())
    {
        return db.MyData.ToList();
    }
}