GLP-1 metabolite regulates glucose
A study conducted by Dariush Elahi and colleagues has determined that the principal metabolite of the gastrointestinal hormone glucagon-like peptide-1 (GLP-1) (7–36) amide, GLP-1 (9–36) amide (GLP-1m), inhibits hepatic glucose production. They assessed glucose turnover during a 2-hour euglycemic clamp procedure during which lean or obese patients were infused with either saline or GLP-1m. A GLP-1 receptor agonist was also administered along with GLP-1m infusion to a group of lean and obese subjects. Whereas lean patients required no glucose infusion to maintain euglycemia during saline or GLP-1m infusion, obese subjects exhibited inhibition of hepatic glucose production while undergoing GLP-1m treatment. Both obese and lean patients required glucose infusion while infused with GLP-1 receptor agonist and GLP-1m. These results demonstrate the antidiabetogenic effects of GLP-1m, which could prove to be therapeutically useful. See page 1501
Sensitivity to bitter taste linked to higher BMI in preschoolers
The postulated link between sensitivity to the bitter-tasting compound 6-n-propylthiouracil (PROP) and an increased risk of obesity is influenced by environmental factors. Studies in different populations have shown a varied and sometimes conflicting association between being a PROP taster and having a higher BMI. Children of lower socioeconomic status are at particular risk of obesity or overweight. The prevalence of obesity has been reported to be about 50% higher in low-income children attending the preschool program Head Start than in the overall preschool population. In their study, Lumeng and colleagues assessed PROP sensitivity in relation to BMI among Head Start preschoolers. They found that preschoolers who were PROP tasters were nearly six times more likely to be overweight than non-PROP tasters. PROP sensitivity and the food aversions that accompany it may serve as a marker for greater risk of obesity among preschoolers whose families' low income may already limit their options for a well-balanced diet. See page 1522
Gender affects stress eating behavior in mice
Stress encourages reward-seeking behavior such as a heightened preference for calorically rich "comfort" foods. This behavior, while increasing the risk of overconsumption and weight gain, is thought to counteract the impact of stress on reward pathways. Women in particular are thought to be at risk for preferential food-seeking behavior because of greater stress sensitivity. A study conducted by Diana Pankevich and Tracy Bale evaluating the impact of gender and stress on food-seeking behavior in mice lends weight to the hypothesis. They found that under conditions of stress female mice more frequently sought out the preferred higher-calorie food than did males. These results highlighting the impact of gender on stress eating could contribute to a greater understanding of the mechanism underlying these behavioral differences and, consequently, the increased incidence of overweight and obesity in women. See page 1539
Parental feeding practices and BMI
Parents who exert too much control over their child's eating habits can unknowingly contribute to overweight by preventing the child from exercising his or her own judgment. A study conducted by Emma Haycraft and Jacqueline Blissett examined whether there is an association between child and parental BMI and the feeding practices employed. They also assessed whether parents accurately reported the degree of control they exercised over their children's eating habits. Whereas fathers reported their feeding practices accurately, no correlation was found between what mothers reported and what was observed, a finding that may have been confounded by the presence of the father during feeding. Parents with higher BMIs were found to be controlling of their children's feeding habits, but no link was found between children's BMI and parental control. See page 1552
