Hello, I am about 5'8 and 17 years old, and am just wondering what a good weight for me would be for me. I was really skinny all through grade school, then gained a LOT of weight in the summer after my first year in high school. I now weigh 170-175 and think 150 would be an ok weight. I just want to lose my stomach and double chin, and make my legs thinner. Any input would be apreciated.