According to the Nutrition Research Center, this is what happens to your body within 1 hour of drinking a can of soda:

-10 minutes: 10 teaspoons of sugar hit your system, which is 100 percent of your recommended daily intake. You’d normally vomit from such an intake, but the phosphoric acid cuts the flavor.

-20 minutes: Your blood sugar skyrockets. Your liver attempts to maximize insulin production in order to turn high levels of sugar into fat.

-40 minutes: As your body finishes absorbing the caffeine, your pupils dilate, your blood pressure rises, and your liver pumps more sugar into the bloodstream. Adenosine receptors in your brain are blocked preventing you from feeling how tired you may actually be.

-45 minutes: Your body increases dopamine production, tricking you into feeling pleasure and adding to the addictiveness of the beverage. This physical neuro response works the same way as it would if we were consuming heroin.

>60 minutes: The phosphoric acid binds calcium, magnesium and zinc in your lower intestine, which boosts your metabolism a bit further. High doses of sugar and artificial sweeteners compound this effect, increasing the urinary excretion of calcium. The caffeine’s diuretic properties come into play. (You have to GO!) Your body will eliminate the bonded calcium, magnesium and zinc that was otherwise heading to your bones. And you will also flush out the sodium, electrolytes and water. Your body has eliminated the water that was in the soda. And in the process it was infused with nutrients and minerals your body would have otherwise used to hydrate your system or build body cells, bones, teeth.
-60 minutes: The sugar crash begins. You may become irritable and/or sluggish. You start feeling like crap. Time to grab another soda!