Whether it's in a piece of fruit, your soda or a pastry, sugar is made up of the same two components: fructose and glucose. The molecular structure and composition of sugar molecules is the same no matter where they come from.
The ratios of fructose and glucose are pretty much the same in both fruit and table sugar. Most fruits are 40 to 55 percent fructose (there's some variation: 65 percent in apples and pears; 20 percent in cranberries), and table sugar (aka sucrose) is 50/50. Neither type of sugar is better or worse for you, but your body processes them differently. Fructose breaks down in your liver and doesn’t provoke an insulin response. Glucose starts to break down in the stomach and requires the release of insulin into the bloodstream to be metabolized completely.