Soda May Age You as Much as Smoking, Study Says

3 minute read

Nobody would mistake sugary soda for a health food, but a new study published in the American Journal of Public Health just found that a daily soda habit can age your immune cells almost two years.

Senior study author Elissa Epel, PhD, professor of psychiatry at University of California San Francisco, wanted to look at the mechanisms behind soda’s storied link to conditions like diabetes, heart attack, obesity, and even higher rates of death. She studied telomeres, the caps at the end of chromosomes in every cell in our body, from white blood cells. Shorter telomeres have been linked to health detriments like shorter lifespans and more stress, cardiovascular disease, diabetes and cancer, the study notes.

Epel and her team analyzed data from 5,309 adults in the National Health and Nutrition Examination Survey (NHANES) from about 14 years ago. They found that people who drank more sugary soda tended to have shorter telomeres. Drinking an 8-ounce daily serving of soda corresponded to 1.9 years of additional aging, and drinking a daily 20-ounce serving was linked to 4.6 more years of aging. The latter, the authors point out, is exactly the same association found between telomere length and smoking.

Only the sugary, bubbly stuff showed this effect. Epel didn’t see any association between telomere length and diet soda intake. “The extremely high dose of sugar that we can put into our body within seconds by drinking sugared beverages is uniquely toxic to metabolism,” she says.

QUIZ: Should You Eat This or That?

Which is better for you: A 1/2 cup of ice cream or 3 scoops of sorbet?
Which is better for you: Half cup of ice cream or 3 scoops of sorbet?Getty Images (4)
Answer: A 1/2 cup of ice cream
Answer: A half cup of ice cream If you eat what you’re craving, you’re more likely to feel satisfied and eat less. And scoop for scoop sorbet contains twice the sugar with none of the filling dairy protein and fat.Getty Images (5); Gif by Mia Tramz for TIME
Which is better for you: Real butter or spray on fake butter?
Which is better for you: Real butter or spray on fake butter?Getty Images; Tara Johnson for TIME
Answer: Butter
Answer: Butter Serving size for spray butters (even low-calorie ones) are around a 1/3 second spray. What on earth does that mean? You're better off using a small amount of real butter as opposed to guessing how much you're using of the mystery melange of up to 20 ingredients.Getty Images (1); Gif by Mia Tramz for TIME
Which is better for you: A sirloin burger or a turkey burger?
Which is better for you: A turkey burger or a sirloin burger?Getty Images (2)
Answer: Sirloin burger Restaurant turkey burgers are often made with dark meat and the skin, so they’re not necessarily better for you (and for the record, they aren't low-fat). You can get a sirloin burger that’s 95% lean meat and gives you 20 g of protein. Just be careful with the toppings.Getty Images (1); Gif by Mia Tramz for TIME
Which is better for you: Almonds or pretzels?
Which is better for you: Almonds or pretzels?Getty Images (2)
Answer: Almonds
Answer: Almonds Almonds are high in protein, fiber and fat and will keep you feeling fuller longer. Give high-sodium pretzels about an hour and you'll feel hungry again thanks to the high-carb no-fat or protein content.Getty Images (1); Gif by Mia Tramz for TIME
Which is better for you: Eggs or Special K?
Which is better for you: Special K or eggs?AP; Getty Images
Answer: Eggs
Answer: Eggs In the morning, you want a meal that will fill you up. Eggs offer protein and fat for satiety, but Special K cereal really only offers carbs and, well, air. If you want carbs to kick off the day, you're better off pairing eggs with a slice of 100% whole grain toast. Getty Images (1); Gif by Mia Tramz for TIME
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Which is better for you: Fat free salad dressing or regular salad dressing?Tara Johnson for TIME
Answer: Regular salad dressing
Answer: Regular salad dressingTo absorb fat soluble vitamins like Vitamins E and K in vegetables you need to consume them with a fat to aid nutrient absorption. Fat-free dressing, meanwhile, is low-calorie but gets its flavor from added sugar and salt.Tara Johnson for TIME (5); Gif by Mia Tramz for TIME
Which is better for you: A low fat cookie or dark chocolate?
Which is better for you: A low fat cookie or dark chocolate?Getty Images (2)
Answer: Dark chocolate “People tend to believe fat free is calorie free,” says Keri Gans, a registered dietitian in New York City. “Go for the real thing.” Fat free cookies may be lower in fat, but higher in other ingredients like sugar. Try a nice piece of dark chocolate for those antioxidants.
Answer: Dark chocolate “People believe fat free is calorie free,” says Keri Gans, a registered dietitian in New York City. “Go for the real thing.” Fat free cookies tend to be high in carbs, sugar and fake sugar. Try a nice piece of antioxidant-rich dark chocolate instead.Getty Images (2); Gif by Mia Tramz for TIME
Which is better for you: Low fat Greek yogurt or 100 calorie Yoplait yogurt?
Which is better for you: Low fat Greek yogurt or 100 calorie Yoplait yogurt?Tara Johnson for TIME
Answer: Low fat Greek Yogurt
Answer: 2% Greek YogurtA little fat is good in the morning to keep you full—plus it has upwards of 17g of protein per container. Fat-free "fruit" yogurt is high in sugar—7 to 10 g per serving—and lower in protein.Tara Johnson for TIME (2); Gif by Mia Tramz for TIME

She also didn’t see a significant link between non-carbonated sugary beverages, like fruit juice, which Epel says surprised her. But she thinks the results might be different if the data were more modern. “We think that the jury’s still out on sugared beverages—theoretically they’re just as bad,” she says. “But 14 years ago people were drinking a lot less sugared beverages…they were mostly drinking soda.” At the time of the study, 21% of adults in the study reported consuming 20 ounces or more of sugar-sweetened soda each day, but soda consumption has been on the decline for years.

Telomere length dwindles naturally as we age, but it may not be an irreversible process. Previous research shows that it’s possible to increase telomere length by as much as 10% over 5 years by stressing less and eating a healthy diet—no soda included.

Read next: Here’s How to Stop Teens From Drinking Soda

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Write to Mandy Oaklander at mandy.oaklander@time.com