Health experts around the world have concluded that it’s time to ban some ads for fast food restaurants, as previously done three decades ago, when the government banned cigarette ads from the airwaves in order to reduce smoking-related illness.

Researchers at the National Bureau of Economic Research say that a ban like this could reduce the number of obese children in the U.S. by as much as 18 percent. This is the first study to make this connection, using data from the 1979 Child-Young Adult National Longitudinal Survey of Youth, commissioned by the U.S. Labor Department. They measure the rate of child obesity against the number of hours of fast food restaurants ads viewed in a given week.

Other studies have shown that 30.3 percent of U.S, aged 6 to 11, are overweight and, furthermore, 15.3 percent are obese. As for adolescents, aged 12 to 19, 30.4 percent are overweight and 15.5 percent are obese. However, fast food isn’t the only problem of overweight teenagers. There has also been a surge in the amount of time children are spending watching TV and playing video games instead of playing outside. Pediatricians have also said that TV can be a negative influence for children’s health, whether the message is in English or Spanish.

By now, two of the largest fast food chains, Burger King and McDonald’s have signed on to the Council of Better Business Bureaus’ Children’s Food and Beverage Advertising Initiative. They pledged to advertise only their healthier products to children under the age of 12. Only three countries – Sweden, Norway and Finland – have banned commercial sponsorship of children’s programs, and study authors acknowledged that the chances of such a ban in the U.S. are slim.