Diet sodas get plenty of heat for being unhealthy, even causing weight gain despite containing zero calories, but a new study found that drinking artificially sweetened beverages while pregnant can actually make your children heavy.

Read: Even More Reasons Not To Drink Soda: New Study Says It May Increase Dementia And Stroke Risk

Researchers looked at data from 1996 to 2002 collected in the Danish National Birth Cohort study, which compiled long-term research from 92,000 pregnant woman living in Denmark. In this original study, participants completed a questionnaire about diets after being pregnant six months. Children’s weight was also captured at the time of birth and again at 7 years old. In the new study, researchers looked at 900 pregnancies where the mother was diagnosed with gestational diabetes, a condition only pregnant woman receive.

About nine percent of the participants consumed at least one artificially sweetened drink per day. The team found that their kids had a 60 percent chance of being heavier at birth, compared to moms who never drank these beverages. At seven years old, these kids were almost twice as likely to have weight problems, according to a release on ScienceDaily.

While many often think that fake sugar is better than real sugar, researchers found no advantages to drinking a beverage using a substitute over the real thing.

"Our findings suggest that artificially sweetened beverages during pregnancy are not likely to be any better at reducing the risk for later childhood obesity than sugar-sweetened beverages," said study co-author Cuilin Zhang, Ph.D., in a statement. "Not surprisingly, we also observed that children born to women who drank water instead of sweetened beverages were less likely to be obese by age 7."

Babies of moms who included real sugar and sugar substitute drinks into their diets had equal chances of being obese or overweight. Moms who only drank water reduced their kid’s risk of obesity by 17 percent.

The team couldn’t determine why this occurred, but cited a study suggesting that artificial sweeteners caused the intestines to absorb blood sugar glucose, however that study was conducted in animals.

As with most scientific studies, there are other pieces of research which state that using sugar substitutes are totally fine. Vice explored the reason behind the discrepancies in a story earlier this year and found that the conflicting research is partially due to the prevalence of studies funded by food makers.

"Right now, the simple answer is this is science versus the food industry," Robert Lustig, neuroendocrinologist at the University of California, told Vice.

Another researcher, Kristina Rother, chief of the National Institutes of Health’s division of pediatric diabetes, told Vice that many are surprised to hear that something without calories could make them fat.

"A lot of people were like, 'Kristina, are you saying something with no calories can cause weight gain?'" she explained to Vice of the reactions she receives. "It was like I was challenging the law of thermodynamics."

Read: Newborn Baby Holding IUD Proves Birth Control Isn't 100 Percent Effective

Rother has published numerous studies on the subject and tells the website that sugar substitutes are not exactly guilt-free.

"I'm not blaming artificial sweeteners for America's obesity epidemic, but I think they're a part of it," she said.

See Also:

Drinking While Pregnant: Baby's Facial Features Changed By Any Amount Of Alcohol, Says New Study

Newborn Baby Holding IUD Proves Birth Control Isn't 100 Percent Effective