A mother's lifestyle can play a significant role in a child's risk for obesity, researchers said.
In a study involving nearly 25,000 children, those whose mothers adhered to five factors comprising a healthy lifestyle – healthy diet, regular exercise, BMI less than 25, non-smoking, and low alcohol consumption – had a 75% lower risk for obesity compared to kids of mothers who didn't adhere to any of these healthy habits (relative risk 0.25, 95% CI 0.14-0.47), found Klodian Dhana, MD, PhD, of Harvard T.H. Chan School of Public Health in Boston, and colleagues.
Children's obesity risk was reduced even when their own lifestyle habits were poor, the group wrote in . Those with a high-risk lifestyle still showed around a 45% lowered risk for obesity when their mothers' led a low risk lifestyle (RR 0.55, 95% CI 0.48-0.63).
However, children saw the lowest risk for obesity when both the mother and the child adhered to healthy lifestyles (RR 0.18, 95% CI 0.09-0.37, relative to families in which child and mother both had unhealthy habits).
"The mechanisms underlying our observations are not completely understood, although the effect of mothers' lifestyle and behaviors could exert a critical impact on their children's lifestyle and diet and subsequently modulate offspring's obesity risk," the group wrote.
Of all the low risk lifestyle factors, a lower maternal BMI was individually tied to the largest single risk reduction for obesity risk in kids:
- BMI 18.5-24.9: RR 0.44 (95% CI 0.39-0.50)
- Moderate/vigorous exercise ≥150 min/week: RR 0.79 (95% CI 0.69-0.91)
- Current non-smoker: RR 0.69 (95% CI 0.56-0.86)
- Alcohol intake (1.0-14.9 g/day): RR 0.88 (95% CI 0.79-0.99)
Interestingly, when broken down by individual lifestyle factors, mothers who adhered to a healthy diet during their offspring's childhood and adolescence -- marked by a Alternate Healthy Eating Index 2010 diet score in the top 40% -- had no association with risk for obesity in offspring (RR 0.97, 95% CI 0.83 to 1.12), which Dhana and colleagues said they didn't expect.
"One potential explanation for our observation of a null association between maternal diet and childhood obesity is that children's energy intake might not be exclusively from meals prepared at home because children's diet is influenced by multiple factors including school and neighborhood food environments and peer influences," the authors explained.
The study included data on 24,289 children who participated in the , who were born to nearly 17,000 mothers. During a 5-year follow-up period, about 5.3% of the children developed obesity.
Lifestyle information on mothers and offspring were collected from self-reported questionnaires, which the authors acknowledged as a potential limitation. Another limitation to the study included a lack of inclusion on paternal lifestyle data and should be assessed in future studies in this area.
Dhana and colleagues highlighted the importance of a healthy lifestyle choices among mothers, adding that these findings are in line with recent clinical trials that showed parent-only interventions were just as effective for childhood weight loss as those involving the whole family.
Disclosures
The study was supported with grants from the U.S. National Institutes of Health.
None of the authors reported any disclosures.
Primary Source
The BMJ
Dhana K, et al "Association between maternal adherence to healthy lifestyle practices and risk of obesity in offspring: results from two prospective cohort studies of mother-child pairs in the United States" BMJ 2018; DOI: 10.1136/bmj.k2486.