It's pretty common to meet a person who doesn't understand why they can't get healthier, and curses the fact that, although they eat all the right things, they are always "a few pounds overweight." They wonder what they're doing wrong, as they proceed to take a gulp of soda, drink a glass of beer, and admit that it's their third day of doing so.
Now, I'm not saying that maintaining a balanced diet while still enjoying the occasional glass of wine or soda can is impossible. It's important to remember, however, that weight gain or weight loss problems can sometimes be down to what you drink as well as what you eat. If you drink a glass of wine a day, or get through a family-sized bottle of soda, you will not be able to maintain a healthy weight.