Weight loss is primarily a matter of what you eat, not what you do for exercise.  Or as the saying goes, weight loss happens in the kitchen, not on the track. 

A healthy weight loss is 1-2 lbs a week. One pound is about 3500 calories.  To do that, you need a calorie deficit of at least 500 calories a day. That can be done by cutting out some foods, switching to lower calorie alternatives and increasing your activity level so that you are burning more calories.  When you run or walk, you burn about 100 calories per mile - more if you are very overweight.  So it takes a while to lose weight solely with exercise.  Exercise will burn some calories and build some muscle, which takes more energy than fat to maintain, but if you really want to lose weight you need to look carefully at what you eat.  Limit eating out as most restaurant meals are much larger and contain more calories than what you would fix at home.  Learn about portion size.  Work on eating more healthy foods (fruit, vegetables, whole grains) and less unhealthy foods (sugar, white flour, etc.)  The closer a food resembles its natural form - the less processed it is - the better. 

I lost about 25 pounds in 7 months last year but since then, my weight loss came to a screeching halt and is even up a bit, even though I have increased my running....So, it's kind of a mystery at times but running will make you feel better whether it results in weight loss or not.

I agree...its all about your consumption.  I was on Yoli's Better Body System (similar to paleo diet in many ways) and lost 25 lbs in 2 months with very little exercise. I know that seems a little fast for most people but I assure you it was all safe....its amazing how your body responds when you cut the refined sugar, decrease carbs, add extra protein, and eat five times a day.  I have a severe sweet tooth so this was difficult at first but Yoli has two whey protein shakes sweetened with stevia and they are heaven.  I make them with a little unsweetened almond milk and it does the trick.  Two a day keeps the cookies away!

Now that I'm a little lighter, I have taken up running again (used to do a lot of it my younger years) and I've fallen back in love.  It has been great to help me maintain my weight loss!

Best of luck to you in your adventure of cutting some pounds...if you are interested in the BBS you can check out at www.yoli.com or come to my website at www.fit2live.mybetterbodysystem.com.

I may have missed something from the original post, but I think you need to provide more information to really get your question answered. Are you referring to the Couch to 5k program and how much weight are you trying to lose? There are so many factors that go into losing weight it is difficult to say with any degree of certainty if you will lose the weight you want to lose with the above mentioned program. I would recommend consulting your physician about what will work for you based on your weight loss goals and lifestyle.

Weight loss should be a simple matter of burning more calories than you consume, and on one level it is. If you add running without changing anything else in your daily activities, you will lose weight over time. The more you run, under these conditions, the more weight you will lose  It is a natural law. In practice, it is very difficult to be sure that you aren't compensating for your new caloric expenditure by increasing calorie intake or reducing other sources of calorie burn that you had before. You begin keeping a food log. If you have a smart phone, there are some nice, free apps for this, like "Lose It." These apps have built-in food databases, calorie targets for different rates of weight loss, goal tracking and reminders to help you keep your food log up to date. You can also use a pedometer to help track your voluntary, non-exercise activity. Or you can just start taking more stairs and parking farther out in the parking lot. Another complication is that we monitor weight loss by taking our total body weight, often only once a week. Total body weight fluctuates with gut fill and water retention, which are both affected by what and when you eat. This can make your body weight fluctuate several pounds from day to day. Weighing more frequently will help you keep these fluctuations in context  Muscle also holds more water and weighs more than fat. Gaining muscle can cause you to gain weight while you are losing fat. You can deal with this by tracking percent body fat or other measures like waist to hip ratio.