Risk of obesity was 56 per cent lower in children of women with a healthy body weight.
Children of mothers who follow a healthy lifestyle have a substantially lower risk of developing obesity, according to a study.
The findings, published in The BMJ, show that risk was lowest among children whose mothers maintained a healthy weight, exercised regularly, did not smoke, ate a healthy diet, and were light to moderate drinkers.
The researchers, including those from the Harvard T H Chan School of Public Health in the US, suggest that if both mothers and their children stuck to a healthy lifestyle, this could result in an even further reduction in the risk of childhood obesity.
Obesity in childhood is associated with an increased risk of several disorders, including diabetes and cardiovascular disease, as well as premature death, in adulthood.
The researchers examined medical history and lifestyle characteristics of 24,289 children aged 9-14 years who were born to 16,945 women in two US studies.
Participants completed detailed questionnaires about their medical history and lifestyle, including body mass index (BMI), physical activity levels and diet. Mothers were also asked about their alcohol intake and smoking history.
Based on this information, the researchers calculated the risk of obesity for each child, using BMI measurements.
Women were on average 41 years old with a mean BMI of 25 and most (93 per cent) were not current smokers. Their offspring were on average 12 years of age, and 46 per cent were boys.
The researchers found that the risk of obesity was 56 per cent lower in children of women with a healthy body weight than children of mothers in other BMI categories.
Compared with offspring of women who were current smokers, children of non-smoking mothers had 31 per cent lower risk of obesity.
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.
Children of mothers who followed all five low risk lifestyle factors (a high quality diet, normal body weight, regular physical activities, light to moderate intake of alcohol, and non-smoking) had a 75 per cent lower risk of developing obesity, compared with offspring of women who did not meet any of the low risk lifestyle factors.