Outlook: Obesity

Tired Teens Running on Empty Calories

Adolescents who sleep less than the recommended 8 hours consume more calories, more fat, and more snacks than their well-rested peers, new research suggests. The results were published September 1, 2010, in the journal Sleep and highlight the relationship between metabolism, appetite-regulating hormones, and sleep.

Susan Redline, MD, MPH, a professor of medicine in the Division of Sleep Medicine at Brigham and Women’s Hospital and Beth Israel Deaconess Medical Center in Boston, authored the study. She and colleagues followed the sleep and eating habits of 240 adolescents for 5 to 7 consecutive 24-hour periods on weekdays.

Compared with those who slept 8 or more hours on average, adolescents who slept less than 8 hours consumed an average of 245 more calories per day, the researchers found. Sleep-deprived teens also consumed a higher percentage of calories from fat and were more likely to report consuming at least 475 calories worth of snacks throughout the day.

The differences are subtle, but could add up to a significant excess of calories and fat over time—experts estimate that a pound of body fat contains approximately 3500 calories. “Short sleep duration may increase obesity risk by causing small changes in eating patterns that cumulatively alter energy balance,” Dr. Redline concluded.

For Diabetes, Diet and Exercise Yield Long-Term Results

An intense regimen of lifestyle changes can help patients with type 2 diabetes sustain long-term weight loss, reduce cardiovascular risk, and improve blood glucose control over time, the results of a randomized clinical trial show.

The Look AHEAD (Action for Health in Diabetes) study recruited 5145 patients with type 2 diabetes, aged 55 to 76 years, who sought treatment at 16 US health centers. Half were assigned to a control group and given periodic diabetes support and education, requiring them to participate in 3 group sessions per year.

The other half were assigned to the intensive lifestyle intervention group. Strict diet and exercise recommendations were reinforced weekly and monthly in group and individual meetings, which continued throughout the 4 years of the study. Patients in this group achieved better results in all markers of type 2 diabetes control.

Patients in the intervention group were also more likely to discontinue their diabetes and blood pressure medications during the study period. The results suggest a greater investment in consistent, ongoing support for diabetes management could be a cost-effective alternative or supplement to medication for the treatment of type 2 diabetes.

Meals Together Don’t Prevent Obesity For All

Children in families who eat meals together are more likely to maintain a healthy weight—or so goes the traditional wisdom on childhood obesity. According to a new report, although the statement holds true for white children, the benefits of family meals are less apparent for black and Hispanic children.

In a study of 16,770 US children aged 6 to 11 years, family meals had no effect on the obesity risk of black girls and only a “marginal” beneficial effect on the obesity risk of black boys. In less educated or single-parent households, Hispanic boys who ate more meals with their families had a slightly higher chance of being overweight or obese than those who ate fewer.

By contrast, non-Hispanic white children who consumed family meals every day were one-third less likely to be obese than those who rarely or never sat down to dinner with their families. Researchers performed the analysis using data from the 2003 National Survey of Children’s Health.

The study did not examine the quality or quantity of food served at family meals, which may account for discrepancies in whether and how they impacted obesity among the children studied. The results appeared in the September 2010 issue of the Journal of the American Dietetic Association.

Antihistamines Tied to Added Pounds, Study Shows

A sleeping culprit in the obesity epidemic may be the widespread use of antihistamines to relieve allergy symptoms. Researchers from Yale University observed an association between prescription antihistamine use and excess weight, the journal Obesity reported in August. Several medications, including histamine-1 (H1) receptor blockers, or antihistamines, are known to impact the body’s ability to regulate weight. The new research confirms that link, but not the physiological mechanisms that produce it.

Lead author Joseph Ratliff, PhD, of Yale University’s department of psychiatry, used data collected from 867 US adults as part of the 2005-2006 National Health and Nutrition Examination Survey. Dr. Ratliff and his team compared antihistamine users to nonusers on the basis of body measurements, blood glucose, insulin concentrations, and lipid levels. Participants who took the allergy-relieving medicines had higher weight, waist circumference, and insulin concentration than those who did not. They were also more likely to be overweight.

The associations do not necessarily mean antihistamines are a direct cause of obesity, but they may be a contributing factor, the researchers concluded.