People deal with stress in various ways, and doctors tell me that one of the most common is to turn to food. (Others, however, find they can't eat when they're under extreme stress. After King David sinned by secretly committing adultery and murder, he later confessed that "my bones wasted away through my groaning all day long" -- Psalm 32:3).
Why do you find yourself overeating when you're under stress? One reason could be that food distracts you from whatever is bothering you. It's also enjoyable to eat, and you may find that food helps you overcome the pain you're feeling from stress. When we're unhappy, we'll often turn to anything that promises happiness, even if it's only temporary.
What should you do? First, put your problems into God's hands, and learn to trust Him for their solution. God loves you, and He is concerned about every detail of your life -- including the things that give you stress. Open your heart to Christ, and commit every detail of your life to Him. Jesus said, "Come to me, all you who are weary and burdened, and I will give you rest" (Matthew 11:28).
Then ask God for wisdom to deal with the problems that cause your stress, instead of trying to escape from them. God knows all about them -- far more than you do. He also knows how they can be solved. The Bible says, "If any of you lacks wisdom, you should ask God... and it will be given to you" (James 1:5).