Five Minutes with Alison G. Hoppin, MD – Assessment and Management of Childhood and Adolescent Obesity

Alison G. Hoppin, MD, is Associate Director for Pediatric Programs, Massachusetts General Hospital Weight Center; Attending Physician in Pediatric
Gastroenterology and Nutrition, Massachusetts General Hospital; Instructor in Pediatrics, Harvard Medical School, Boston, Massachusetts.Bariatric Times • March 2007

How are children and adolescents physically and emotionally unique in the field of obesity?

Dr. Hoppin: No general observations will apply to everyone, but there are some ways in which children and adolescents are unique. First, their bodies may be more responsive to healthy lifestyle changes than the bodies of adults. There is an excellent study¹ showing that an eight-month intervention to improve lifestyle using family-based behavioral techniques led to improved weight control 10 years later. With the exception of surgery, no interventions in adults have that type of long-term effect.

Children might be more responsive to lifestyle change because many lifestyle habits are learned early in life. However, there may be physiological reasons for the phenomenon: It appears that nutritional factors and perhaps some other environmental influences can change the “metabolic program” of an individual, permanently affecting his or her susceptibility to obesity and metabolic disease. We don’t yet know how or when this “programming” occurs, but it is currently an important subject of research. Meanwhile, it provides an additional reason to focus efforts on early intervention to prevent obesity, including supporting women to have healthy nutrition before and during pregnancy.

Children and adolescents feel many of the same emotional burdens as do adults with obesity. At times, they suffer acutely because of direct teasing from peers, and because peer acceptance is so important to this age group. The family also strongly influences the adolescent’s lifestyle habits, self esteem, and body image. Families can be very helpful to their children by modeling healthy lifestyle habits, working cooperatively with their children to improve the diet and activity of all family members and limiting unhealthy habits such as television viewing. Parents and other family members can also help support a positive body image by focusing on health and strength, and not directly on weight and appearance. Conversely, parents can present obstacles to a child’s progress if they are unwilling or unable to change their own lifestyle habits, and if they use critical or overly restrictive approaches to try to control their child’s weight.

What are your thoughts on “dietary supplements” now being marketed as “weight loss” treatments for children?

Dr. Hoppin: The big problem with dietary supplements in general is the almost complete lack of scientific evidence behind the manufacturer’s claims. Even in cases where studies are cited, a close look usually reveals major flaws in the studies. I have not seen any dietary supplements for which there is any reasonable claim that they are useful for weight loss. For most of them, very little is known about safety, so it is possible that some are downright dangerous. Furthermore, if consumers believe the claims of weight loss, they are likely to spend resources and energy that would be better invested in something else to support weight loss, like sports programs for their children.

How do you feel about the legislative climate surrounding dietary supplement marketing practices?

Dr. Hoppin: There can and should be a greater level of accountability in this industry. Relying on federal watchdogs to pick up the most egregious cases of false advertising is not enough. The public cannot be expected to cor

rectly interpret claims of “evidence” because in most cases, there is little or no reliable information. There may be some merit in some of the products that fall into the category of dietary supplements, but we will never know which ones are useful or safe unless they are submitted to more rigorous scientific study and review. I applaud the general trend for good science within the realm of alternative medicine, and I hope that the trend will extend to examine the claims of the products marketed as dietary supplements.

What should bariatric care professionals advise adolescent overweight and obese patients and their parents of regarding lifestyle and diet?

Dr. Hoppin: Many of the principles that apply to adults also apply to overweight adolescents, but a few reminders may be helpful: 1) develop realistic goals, focusing on specific, appropriate lifestyle changes rather than a weight loss goal; 2) emphasize physical activity, both structured and unstructured—reducing TV viewing to a maximum of 1 to 2 hours/day is an important early goal, as this is one of the best established causal associations with obesity in children; 3) work to change lifestyle for the entire family, rather than singling out the adolescent him or herself; 4) teach the family to be proactive and supportive, but not critical or controlling of the overweight child.

You may need to remind parents that there is a biological reason why some people gain weight easily, and that the fact that their child is overweight does not necessarily mean that he or she is not trying.

Please tell us your thoughts regarding both genetic influences on obesity and developmental influences on obesity.

Dr. Hoppin: The genetic influences on obesity are very real, and are likely responsible for a large part of the variation of body weight within a population in a given environment. The environmental influences are responsible for the changes in obesity in that population over time. The specific mechanisms of the genetic contributors to obesity are only partly understood. The problem is complex, because many genes are involved in the susceptibility to obesity, and the phenotype is also affected by environmental influences. As a result, isolating the genetic contributors to obesity is far more difficult than it is for diseases in which a single gene causes a recognizable phenotype. We currently know about a handful of rare genetic defects that contribute to obesity, but the common genetic defects associated with obesity are not well defined.

Do you see metabolic syndrome in children and adolescents?

Dr. Hoppin: The definition of metabolic syndrome in children and adolescents is not as well defined as it is in adults, but many adolescents have features that are similar to the metabolic syndrome in adults. Type 2 diabetes is increasing, but is still uncommon even among obese adolescents (perhaps 4% of adolescents with severe obesity). However, many other adolescents have some evidence of insulin resistance, as recognized by high fasting insulin levels, moderate elevations of fasting glucose, or the rash acanthosis nigricans. These features suggest a risk of the metabolic syndrome pattern in the future.

Of the myriad of obesity therapies currently practiced, which do you find most effective in adolescents and why?

Dr. Hoppin: Perhaps the most important approach to adolescent obesity is prevention. Intervention earlier in childhood to help change a family’s lifestyle habits and develop a healthy “feeding relationship” can be the most valuable tool. Establishing and supporting healthy habits of physical activity and minimizing television viewing are important targets.

If an adolescent has established obesity, it is important to identify and work on specific problem areas. If the family dynamics are not supportive of a healthy lifestyle or undermine the adolescent’s cooperation, then this may be the first important target. A group-based, family-focused approach can be a powerful tool, because it can give families insight into their own relationships and how they can be reshaped to support weight control. If adolescents are willing to participate, a group-based approach can also give them peer support that fosters a more positive self image and confidence that they can be successful.

All that said, there is minimal evidence to support any specific dietary or behavioral approach in children or adolescents. The field greatly needs good quality clinical research to establish which interventions are most valuable.

Time’s up!

1. Epstein LH, Valoski A. Wing RR. McCurley J. Ten-year follow-up of behavioral, family-based treatment for obese children. JAMA 1990;264:2519–23.

“Perhaps the most important approach to adolescent obesity is PREVENTION.”

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