Root beer and Coca-Cola are nutritionally similar, but root beer has a few modest advantages: it’s almost always caffeine-free, and it’s significantly less acidic, which means less potential damage to your teeth. Neither drink qualifies as healthy, though, and the calorie and sugar counts are nearly identical.
Calories and Sugar Are Almost Identical
A 12-ounce can of Coca-Cola Classic contains about 155 calories. A 12-ounce can of A&W, Barq’s, or Mug Root Beer contains 152 calories. That three-calorie gap is meaningless in practical terms. Both drinks get virtually all their calories from sugar, delivering roughly 38 to 39 grams per can. That’s close to 10 teaspoons, which already approaches or exceeds the daily added-sugar limit recommended by most health organizations.
If your main concern is weight management or blood sugar, switching from Coke to root beer won’t make a noticeable difference. You’d need to cut back on both or switch to water, seltzer, or an unsweetened alternative.
Root Beer Is Caffeine-Free
Most root beer brands contain zero milligrams of caffeine. Coca-Cola, by contrast, has about 33 mg per 8-ounce serving, which works out to roughly 50 mg in a standard 12-ounce can. That’s less than a cup of coffee but still enough to affect people who are sensitive to caffeine, pregnant, or trying to limit their intake.
One exception worth noting: Barq’s Root Beer does contain a small amount of caffeine in its regular (non-diet) version, so check the label if caffeine is something you’re actively avoiding. Every other major root beer brand is caffeine-free.
Root Beer Is Much Easier on Your Teeth
This is where the two drinks differ most. Acidity is the primary driver of tooth enamel erosion from soda, and Coca-Cola is far more acidic than root beer. On the pH scale, where lower numbers mean more acid, Coca-Cola Classic measures around 2.37. A&W Root Beer sits at 4.27, and Barq’s Root Beer at 4.11. For context, pure water is 7.0 (neutral), and battery acid is about 1.0.
That gap matters more than it might look. The pH scale is logarithmic, so a difference of nearly two full points means Coca-Cola is roughly 50 to 80 times more acidic than most root beers. Drinking root beer still exposes your teeth to sugar, which feeds the bacteria that cause cavities, but the enamel erosion risk from the acid itself is substantially lower. If dental health is a priority and you’re going to drink soda either way, root beer is the better pick.
Caramel Coloring in Both Drinks
Both Coca-Cola and many root beers get their brown color from caramel coloring, which can contain a compound called 4-MEI that forms during the manufacturing process. California’s Proposition 65 flagged this compound as a potential carcinogen, and it has drawn ongoing scrutiny. Studies measuring 4-MEI in cola soft drinks have found levels ranging widely, from about 10 to over 300 micrograms per liter depending on the brand and whether the product was canned, bottled, or dispensed from a fountain.
Root beers that use caramel coloring also contain 4-MEI, though some brands use other coloring methods. The concentrations in any single can of soda are low enough that regulatory agencies like the FDA have not restricted them. Still, if you drink multiple sodas a day, cumulative exposure adds up regardless of which brown soda you choose.
What About Diet Versions?
Switching to diet root beer or Diet Coke eliminates the sugar and drops calories to zero or near zero. Both types of diet soda typically use artificial sweeteners like aspartame, acesulfame potassium, or sucralose. The safety debate around these sweeteners is ongoing. The International Agency for Research on Cancer classified aspartame as “possibly carcinogenic to humans” (a category that also includes things like pickled vegetables and aloe vera extract), though the FDA has maintained that current evidence does not show aspartame causes cancer at normal consumption levels.
Diet root beer does retain its acidity advantage over Diet Coke. A&W Diet Root Beer has a pH of about 4.57, still far less acidic than any cola. So even in diet form, root beer is gentler on enamel.
The Bottom Line on Choosing Between Them
Root beer wins on two specific fronts: no caffeine and significantly less acid. Those are real, measurable differences that matter for your teeth and for anyone managing caffeine intake. On sugar, calories, and overall nutritional value, the two drinks are essentially interchangeable. Neither provides vitamins, minerals, or any meaningful nutrition. If you’re choosing between the two at a restaurant or a vending machine, root beer is the marginally better option. If you’re trying to improve your health in a lasting way, the bigger move is drinking less of either one.