Obesity and implications for future generations

Abstract

There is little debate that obesity has reached epidemic proportions. At last count, at least one-third of adults in the United States were obese, and all states, except Colorado, have experienced a doubling in obesity rates from 1980-2007. Should this upward spiral ontinue, projections for 2030 suggest 0% and 80% of the worldwide populaion will be obese or overweight, respecively. Several methods define obesity skin fold, % of ideal body weight, waist: ip ratios, body mass index [BMI]); owever, BMI (weight [kg]/height [m) s the most often used method, which denes a BMI of 24.6 kg/m as overweight and of 30 kg/m as obese. To lace this in perspective, a weight of 12454 lbs is a normal BMI for a woman ho is 5 feet 6 inches tall. Remarkably, 0% of adult women are unable to mainain their weight within the range of a ormal BMI. The prevalence of obesity during pregnancy has prompted the Institute of Medicine (IOM) to recommend new guidelines for gestational weight gain (GWG) during pregnancy. Nonetheless, obesity that is independent of GWG has been associated with adverse outcomes for both mother (miscarriage, thromboembolism, diabetes mellitus, preeclampsia, hemorrhage, cesarean section delivery, wound infection) and infant (congenital anomalies, stillbirth, neonatal death). Adherence to the IOM GWG guidelines, however, is difficult for many women. In a population-based study that assessed GWG, Chu et al demonstrated that approximately 40% of normal weight women and 60% of overweight women gained more weight during pregnancy than recommended. Obese women gained less weight as a group compared with the normal and overweight groups; however, approximately 25% still exceeded IOM recommendations. In addition, GWG was increased in women who were 19 years old, white, or 12 years of education. If pregnancy can be considered a window to future health, excessive GWG is a first glimpse at unhealthy trends that lead to adverse outcomes that are associated with obesity. An examination of the Danish National Birth Cohort by Nohr et al identified GWG as a determinant of long-term obesity. Obese women with GWG of 10 kg were below their prepregand were able to reduce their BMI; by contrast, 12% of overweight and 14% of obese women with excessive GWG, respectively, moved up a BMI category. Each successive pregnancy potentially allows for successive weight gain that perpetuates the obesity cycle and increases risks for cardiovascular disease, metabolic syndrome, and diabetes mellitus in later life. If the window during pregnancy provides a picture of adverse health consequences for mothers, what vision is revealed for the offspring? The increase in obesity of children mirrors the epidemic rise that is seen in adults. In adults, obesity is defined using a BMI cutoff of 30 kg/m; the more acceptable definition of obesity for children is a BMI of 95th percentile, specific for age and gender. Overweight is defined as a BMI between the 85th and 95th percentiles. Data suggest that 37.1% of infants are overweight and that 16.9% of children and adolescents are obese. In addition, evidence suggests that the trend toward obesity starts as early as 6 weeks. Using a nested case control design, McCormick et al demonstrated a 16% prevalence of infant obesity and also noted children who were obese at age 24 months were more likely to have been obese at age 6 months (odds ratio, 13.3; 95% confidence interval, 4.50– 39.53). Although additional evidence will be needed, this study suggests that interventions for obesity may need to be initiated early in infancy. The Bogalusa Heart Study included 12,000 children. EightyFrom the Department of Obstetrics and Gynecology, The University of Texas Medical Branch, Galveston, TX. The author reports no conflict of interest. Presidential address presented at the 78th Annual Meeting of the Central Association of Obstetricians and Gynecologists, Nassau, Bahamas, Oct. 26-29, Reprints: Gayle Olson, MD, Department of Obstetrics & Gynecology, The University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-0587. golson@utmb.edu.