An Update from James O. Hill, PhD, on Energy Balance

Several years ago, ACFN asked several experts in the field to write a white paper on our scientific understanding of energy balance.  James O. Hill, PhD, co-founder of America on the Move, and Holly R. Wyatt, MD, both with the University of Colorado Health Sciences Center; along with Judith Young, PhD, American Alliance for Health, Physical Education, Recreation, and Dance and John C. Peters, PhD, co-founder of America on the Move, developed this paper titled, “Achieving Energy Balance in the Population: A Solution for the Obesity Epidemic.”  ACFN thought the time was right to revisit this topic, so ACFN President and CEO Susan Finn, PhD, RD, FADA, asked Dr. Hill a few questions. Dr. Hill is regarded as the pioneer in encouraging Americans to improve their health by making small changes in the calories they eat and how active they are in daily life.

Susan Finn: Where are we in the debate over whether diet or exercise is the chief driver of weight loss and weight management?

James Hill: Frankly, we are wasting a lot of time on this debate – time better spent on finding a unified solution to the obesity problem. We need a strategy that integrates diet and exercise; we cannot do without either one and maintain health. The recent article in Time magazine (“Why Exercise Won’t Make You Thin,” August 9, 2009) did a real disservice to the people working in the field and to the public. A lot of research suggests that it is not the case that when sedentary people become active, their food intake increases to match their increased activity.

Finn: Would you elaborate on a concept you discuss in your paper – namely, that at our current level of energy expenditure, we simply cannot achieve a low enough energy intake to reach energy balance.

Hill: All our physiological systems drive us to eat. Eating is good thing. An enormous amount of data suggests that food restriction is not an effective strategy for weight management.  It is not possible to get people to follow a restricted diet over time. Every study shows that when focusing only on food, people regain the weight they lose. Physical activity is necessary to keep the weight off.

Finn: People may be surprised to learn that energy balance can occur at any weight – even obesity. Of course, the goal is to achieve energy balance at the healthy weight, right?

Hill: Right. But the fact is that not everyone can be skinny. We have to take variables like genetics and physiology into account. People need realistic goals. We’ve been telling people who need to lose weight to adjust their lifestyle. That approach hasn’t worked. It’s time to switch it up – consider lifestyle first, then weight. In other words, given my lifestyle, here is what I can do and succeed.  

Finn: You set forth several goals in your paper: 1. Increase the level of physical activity in the population with small gradual steps; 2. Improve dieting behaviors to reduce excess energy intake – eat smarter; and 3. Help children develop energy balance skills. Do you still support these goals?

Hill: Absolutely. We must increase physical activity in the population, and we must forget the concept of food restriction. It doesn’t work. Instead, we should be focusing on portion size and energy density. And finally – and this is most critical of all – we must empower our children with skills for achieving energy balance in their own lives.

Finn: Is there anything else you would like to stress or add to the information in your earlier paper?

Hill: Yes, I have two observations. First, the same “making small changes” approach we have been promoting in personal eating and activity behavior can be applied to the food industry as well. For example, what if a large burger became 5% smaller a year over five years? If the fast food companies made those burgers 25% smaller tomorrow, customers would complain about losing value. But making small reductions over time could change consumers’ expectations and their value equation. It’s a long-term approach, but large portions didn’t happen overnight and it’s not going away overnight either.  Second, it’s always going to be harder to lose weight than to prevent weight gain in the first place. After a certain point, an obese person’s metabolism is permanently altered. We should continue to help these people with treatment, but as a society, our emphasis needs to be on prevention.