God gave us each a sound mind, self control, and common sense. He is not a genie in a bottle and He is not in the business of being a respecter of people. Anything he has gifted you to do for yourself in the natural, he is not going to wave a magic wand over you and allow you to get by without your own effort involved. God is your Creator, Savior, Father and Friend. He deserves our respect and consideration. When we bring our petitions to him, it should be with thoughtfulness and forethought as to whether it's something he has graced us to take care of ourselves.
To lose weight, one must do the traditional mantra of eat less and exercise more. Fresh air, sunshine, and a brisk walk are beneficial for every remotely able body. Diet need not be extreme in any direction. A reduction in sugar, regular dairy and processed fake food including white bread, an increase in lean, grassfed meats and plant based carbs including an abundance of fruits and vegetables that are fresh and in season will yield the desired results in a few months. This is doable and not a pipe dream. I followed this advice myself starting in May 2013 and I have lost 80 pounds so far.
The denomination that I grew up in is especially bad about having gluttony and laziness as their "secret acceptable sin" and it can be hard to get away from that cultural influence once it's a part of your cellular memories and self talk, it is doable. Also, it's obviously no secret sin as we can see the results as plain as day and they have had some hand in making almost all of America have a morbidly obese rate hoovering above 30%.
Good luck and God Bless you!