Don’t be swayed by the pretty imagery on cans and bottles of “natural” sodas or by their healthy-sounding ads.
Typically, these sodas are just carbonated sugar water—and as caloric as regular sodas. Most contain cane sugar or “real sugar” (that is, sucrose) instead of high fructose corn syrup, but sugar is sugar. Some natural diet sodas contain stevia extract (from a South American shrub), but there’s no evidence it’s more healthful than other sugar substitutes.
A few exceptions are made from fruit juice and carbonated water, with no additional sugars, though they may still have lots of calories.
For a no-calorie alternative, try flavored seltzer water (make sure it has no added sugar), or add seltzer to a little fruit juice.