If you want to use running to lose weight, you may want to consider getting the okay from physician to start. Also, to help to make sure that you're successful with this, you might want to consider looking into getting a sports nutritionist or dietitian. This person will make it a lot easier to help you with the direction in where you're going so that you reach your goals.
Sometimes when you use running to lose weight you'll reach a plateau and this because you might be doing the same training program week after week. What you need to do at this point is change your routine. Maybe you're not doing strength training on the side. Maybe you can incorporate a speed workout or a hill workout. These things will challenge a different part of your body and get that fat burning system going to help challenge you a little more and help you reach your goals.
So there are different things you can do with running to lose weight. Maybe you can increase miles for your long runs. The longer you go over about an hour, hour and a half, your body start to incorporate a fat burning process. But a key part of that is that you actually need to take calories in while you're running to help to continue that fat burning process. It seems counter productive but that's not exactly true. Fat burns in the flame of carbohydrates. So to keep that fat burning process going you need to actually take calories in. If you're going for about 45 minutes to an hour, after that you want to start to take in about 100 calories maybe every 30 minutes, but keep that pace going.
To help with the weight loss try to vary up your running routine. Your body can actually get bored by doing the same workout each time, week after week. So vary it. You can do a speed workout one day a week, you can do a long run on your weekends, and maybe find time for a tempo workout later in the week. So maybe speed, Tuesday, Wednesday. Tempo, Thursday or Friday and do your long run on the weekend. It'll challenge various parts of your body and keep that fat burning going so that you continue to lose weight