What Does Drinking Soda Do to Your Body?

Updated July 2026

Soda is the drink of choice for millions of Americans — about 40 gallons per person a year, nearly a gallon a week.

How much sugar is in a can of soda?

About 10 teaspoons — roughly 160 calories of pure sugar. Since about 100 extra calories a day can add 10 pounds in a year, a single daily can can put 15 pounds on you in short order. It's no mystery why two-thirds of US adults are overweight or obese and childhood obesity has nearly quadrupled in three decades.

What does soda do to your health?

Far more than add weight. The Harvard School of Public Health reports that people who regularly drink sugary drinks — one to two cans a day or more — have a 26% higher risk of type 2 diabetes; one can a day is tied to a 20% higher risk of having or dying from a heart attack, and a 75% higher risk of gout. Soda is hard on teeth and bones, too. And diet soda can be just as damaging.

What happens in your body after you drink one?

A fast cascade of sugar, insulin, and caffeine. Within minutes, about 10 teaspoons of sugar hit your system, with phosphoric acid cutting the sweetness so your taste buds don't revolt. Blood sugar spikes, insulin surges, and the liver begins converting that sugar into fat. Around the 40-minute mark caffeine finishes absorbing, nudging up blood pressure and blocking the brain signals that would otherwise make you feel tired, while dopamine rises and lights up the brain's reward centers. Then, as insulin clears the sugar, you crash — sluggish and irritable — and the easiest fix on offer is another soda. That reward-and-crash loop is a big part of why soda is so hard to put down.

The larger lesson goes beyond soda: everything we put in our bodies has complex effects, and "it's on the shelf and tastes great" is no guarantee it's harmless. Plenty of processed foods share that problem — which is the opposite of how we build Step One Foods, where every ingredient is chosen and studied to promote health.

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