What could be the effects their moms have. Now one in five children aged between six to 19 years old are obese.
From all of the children, scientists noted that 1,282 of them - or the 5.3 percent - suffered from obesity.
Moms' healthy lifestyles did not necessarily translate into children's healthy lifestyles in this study, but when they did, offspring had an 82 percent lower risk of being obese, compared to when mothers and children had high-risk lifestyles.
Children of mothers who exercised for the recommended 150 minutes or more a week - and who were light to moderate drinkers (1-2 small glasses of wine or a pint of standard strength beer a day) - also had a lower risk of obesity compared with children of mothers who did not exercise and who did not drink alcohol.
The study included data on 24,289 children who participated in the Growing Up Today Study, who were born to almost 17,000 mothers. They were the offspring of nurses who had been enrolled in the Nurses' Health Study II in the early 1990s.
As the part of the study, nurses have to fill up the answers to certain questions regarding the lifestyle, habits, alcohol consumption, smoking, health, diet and exercise patterns. According to the study, genetics play an important role in obesity, but researchers think lifestyle factors may be behind the increased rate in recent decades.
"Our study was the first to demonstrate that an overall healthy lifestyle really outweighs any individual healthy lifestyle factors followed by mothers when it comes to lowering the risk of obesity in their children", said Qi Sun, assistant professor in the Department of Nutrition.
However, mothers who followed all five habits boasted a 75% lower risk for their kids becoming obese than mothers who followed none of those habits.
"Living a healthy lifestyle cannot only help adults to improve their health and reduce their risk of developing chronic diseases, but also can exert health benefits to their offspring", Dr. Qi Sun from Harvard T.H. Chan School of Public Health, Boston, told Reuters Health by email.
The research, which used data from more than 76,000 adults, found the increase in BMI was down to factors including greater availability and consumption of high-energy, low-nutrient foods and lower levels of physical activity. During a median follow-up period of five years, just over 5 percent of the children became obese.
It is not a matter to consider that what a mother ate when she was pregnant as a maternal diet alone is not responsible for the obesity. What children eat at school also gets a chance of affecting the diet of children. The biggest contributing factor was whether or not mothers maintained a healthy weight - children of mothers whose BMI qualified as obese were more than three times as likely to become obese.
Neither sex or age of the child is clearly linked to the obesity factors.
So an global team based in Canada and the United States of America set out to investigate whether mother and child lifestyle factors have an effect on the risk of childhood obesity. "For children themselves, [it's important] to limit the food items that increase insulin resistance".