Soda. It has become the four-letter word of beverages. Of all the drinks on the market, soda probably has the worst reputation. Science and medical research point their collective finger at soda, and blame it for everything from diabetes to tooth decay, hyperactivity to childhood obesity. But is soda really that bad for you?

When asked if soda is inherently unhealthy for people, board-certified nutritionist and author Jonny Bowden, PhD, CNS, said, "Yes. Simple, unequivocal answer, yes. Yup. Affirmative. Absolutely." What's so unhealthy about many Americans' favorite beverage?

To get to the truth, let's start with the ingredients. The average cola contains carbonated water, caramel color, natural flavors, caffeine, phosphoric acid and high-fructose corn syrup. Carbonated water is plain water infused with carbon dioxide, which creates the bubbles. Caramel color is a natural additive that tints food products, providing the familiar color consumers expect to see. Natural flavors are often of the citrus variety and added for taste. All of these are simple, harmless ingredients. Next is caffeine, a diuretic and stimulant known to be addictive.

What's left on the list of ingredients is what solidifies soda's bad name: sugar. Phosphoric acid is a chemical that adds a tangy or sour flavor by breaking down starches into sugar. According to Bowden, we should consume as little sugar as possible, especially refined sugar. "Zero would be a bull's-eye but is pretty much an unobtainable goal," says Bowden.