Outlook: Obesity

ADHD Symptoms Linked to Future Obesity

New evidence shows that children who have trouble staying on task are also more likely to struggle with their weight. In a large retrospective analysis, researchers from Duke University Medical Center identified a link between obesity and the symptoms of attention-deficit hyperactivity disorder (ADHD).

The relationship is linear—meaning that the more ADHD symptoms a child has, the greater the likelihood that he or she will become an obese adult. “This is the first study to take this concept out of the clinic and into the population and show that it’s not just the diagnosis of ADHD that matters; it’s the symptoms,” said Scott Kollins, PhD, who coauthored the study.

Symptoms such as hyperactivity, impulsivity, and inattention could interfere with children’s ability to self-regulate, according to lead author Bernard Fuemmeler, PhD, MPH. This could not only explain why some people may be more vulnerable to obesity, Dr. Fuemmeler said, but also guide efforts to prevent the condition. Drs. Kollins and Fuemmeler examined the medical records of 15,197 adolescents gathered as part of the National Longitudinal Study of Adolescent Health, conducted from 1995 to 2009. Compared with those who reported no symptoms, children with 3 or more symptoms of ADHD had a higher initial body mass index during adolescence and a 63% chance of obesity in adulthood.

“The most exciting thing about this research is, it gives us a thread to follow in determining why kids with ADHD symptoms might be at risk for developing obesity,” Dr. Kollins said. “It establishes the path for identifying these kids earlier and focusing on intervention methods.”

The results were published in the October 26 online issue of the International Journal of Obesity.

Fit Bodies Burn Fat More Eficiently

A recent study confirms what most fitness buffs have known all along— burning fat is easier when you’re in shape. By studying concentrations of fat-burning molecules in the blood, researchers discovered that fit individuals show a significantly different “metabolic signature” after exercise than sedentary individuals.

The finding paints a more detailed picture of the mechanisms behind exercise and could pave the way for a new generation of pharmacologic treatments that mimic its benefits, according to lead researchers Gary Lewis, MD, and Robert Gerszten, MD, of Massachusetts General Hospital.

Drs. Gerszten and Lewis tracked more than 200 different metabolites in the blood plasma of participants before and after they engaged in physical activity of varying duration and intensity. Across the board, an increase in metabolites was correlated with higher levels of fitness.

When the researchers applied their analysis to a group of marathon runners, they found that the runners burned fat 1000 times more effectively. Even after just 10 minutes of exercise, fitter people showed a stronger metabolic response that lasted at least an hour after they quit exercising.

It remains unclear whether the effects are the result of fitness training, genetics, or a mixture of both, the report’s authors noted.

Exercise Combo Improves Fitness and Diabetes Control

Combining strength training with aerobic activity is a winning formula for fighting excess body fat, improving overall fitness, and lowering blood sugar in patients with type 2 diabetes, according to a new study. The results were presented in October at the Obesity Society’s 28th Annual Scientific Meeting in San Diego, California.

“The study shows that the combination approach of aerobics and strength training has greater cumulative benefit” than either type of exercise in isolation, said the study’s lead author Timothy Church, MD, PhD, director of preventive medicine research at the Pennington Biomedical Research Center in Baton Rouge, Louisiana.

As part of the Health Benefits of Aerobic and Resistance Training in Individuals with Type 2 Diabetes Study, Dr. Church and colleagues enrolled 262 women and men aged 30 to 75 years in 1 of 4 exercise programs: self-directed exercise, supervised resistance training, supervised aerobic training, or a combination of supervised resistance and aerobic training.

Participants who engaged in strength and aerobic training for just 140 minutes per week lost an average of 3 lb of body fat, shaved 1 inch off their waistlines, and showed significant improvements in hemoglobin A1C measurements.

The findings reinforce a key counseling point for patients with diabetes, and provide support for incorporating weightlifting and aerobic exercise into any diabetes management program.