Apparently cigarettes are not the only thing teenagers should avoid.

A new study from Swedish researchers has found that being obese at age 18 increases the risk of premature death in adulthood and is equivalent to smoking more than 10 cigarettes a day.

Dr. Martin Neovius of the Karolinska Institute in Sweden examined the cause of death in more than 45,000 men who had their body mass index measured (BMI) and reported that they smoked at age 18. The men were followed up for an average of 38 years.

In that time, 2,897 of the subjects died with the incidence of death highest among those who were obese when they were young.

The researchers found being underweight didn’t increase the risk of death in adulthood, though people who were seriously underweight (BMI less than 17) carried the same risk in people who were overweight.

Those who smoked more than doubled their risk of premature death.
However, when obesity and heavy smoking were combined, researchers found no statistical difference between the two, prompting the researchers to claim being obese increased risk of premature death, regardless of smoking habits.

Some people have turned to nutritional supplements for weight loss.