Weight

Drinking one soda a day is equal to consuming 39 pounds of sugar per year.  Drinking sugary drinks on a regular basis interacts with the genes that affect weight.  Sugar-sweetened beverages are linked to more than 180,000 obesity-related deaths per year.

Brain

Having too much sugar in your diet reduces production of a brain chemical that helps us learn and store memories.  Consuming too much sugar also dulls the brain's mechanism for telling you to stop eating.

Kidneys

The high levels of phosphoric acid in sodas have been linked to kidney stones and other renal problems.

Digestive System

The carbonation in sodas can cause gas, bloating, and cramping.  Caffeine can also worsen episodes of diarrhea or contribute to constipation.

Bones

Drinking sodas has been linked to osteoporosis (disease that weakens bones) and bone density loss, likely due to the phosphoric acid and caffeine found in most sodas.

Heart

Drinking sodas over a long period of time leads to an increase risk of heart disease, including heart attack and stroke.

Lungs

The more soda you drink, the more likely you are to develop asthma or other lung conditions.

Teeth

The high levels of acid in soda corrode your teeth.