Does Drinking Sparkling Water Make You Hungry?

The ubiquity of sparkling water in 2018 is so widespread that I'm finding those gleaming cans everywhere from office fridges to backyard coolers to poolside snack bars. We know sparkling water hydrates as well as regular water, but today I came across a question I'd never considered: Does sparkling water make us feel hungry? Monica Reinagel, a board-certified, licensed nutritionist and professionally trained chef who writes as Nutrition Diva, answers this question in a recent article that my fellow fizzy water addicts will want to read.

Her response focuses on a peptide hormone called ghrelin, which is known to be an appetite stimulant. In 2017, researchers found that male rats consuming carbonated water gained weight at a faster rate than those consuming still water due to elevated levels of ghrelin. The same researchers then conducted a follow-up experiment with 20 healthy male adults and found that ghrelin levels increased when they drank carbonated water compared to a control beverage. Scientists concluded: "These results implicate a major role for carbon dioxide gas in soft drinks in inducing weight gain and the onset of obesity via ghrelin release and stimulation of the hunger response in male mammals."

Ah shit, we're screwed! Damn you, Pamplemousse LaCroix! Well, not so fast, Reinagel writes. She notes the small sample size of the human trial (and its all-male participants), and points to a perhaps contradictory study that found humans' ghrelin levels were lower after drinking caloric drinks like milk and regular soda.

But Reinagel's biggest grain of salt is this: One hormone alone doesn't translate to whether or not you feel super hungry, or whether you then eat an entire pizza. "The differences in ghrelin levels after various fizzy and non-fizzy beverages did not predict how hungry people actually felt or how much they ate at subsequent meals," she reminds us. So sure, you might have elevated ghrelin levels after drinking a sparkling water, but if the bubbles somehow make you feel fuller, you might not snack afterwards.

It seems as though the science is still unclear as to whether sparkling water actually makes us feel hungrier or eat more. That's fine by me. I'll continue shotgunning these pastel cans until I see a definitive link between them and cancer. In the meantime, go check out Nutrition Diva's full post for more of the science behind this.