The science on calorie balance is compelling, but the perception is still surprisingly hazy. With recent attention on “who” and “what” is to blame for obesity, we think it’s important to re-emphasize the main points that seem to be missed in recent discussions on this topic:
1) Scientists and government agencies agree that “Energy Balance” is key.
The word “balance” is defined as “a condition in which different elements are equal or in the correct proportions.” Just like balancing our checkbook with the money we earn and the money we spend, “energy balance” is a relationship between two factors: food and physical activity. Despite what some headlines would lead you to believe, scientists agree that both food and physical activity are important parts of the obesity equation.
Energy balance occurs when the amount of calories consumed or eaten from all foods and beverages equal the calories expended or burned. Awareness of calorie needs and the amount of calories burned during various activities is the first step toward achieving energy balance and a healthy weight. When we tip the balance and eat and drink more calories than we burn, weight gain occurs. When we eat and drink fewer calories than we burn, weight loss is the result.
The concept of “energy balance” is well supported in the research by respected leaders in the field such as James Hill, a professor at the University of Colorado School of Medicine. Hill’s research has shown that our best strategy for reversing the obesity epidemic is to focus on preventing positive energy balance in the population through small changes in diet and physical activity. Hill and other scientists have consistently argued that the impact of diet and physical activity together on energy balance must be considered.
According to John Jakicic from the University of Pittsburgh during IFIC Foundation’s Webinar “Energy Balance at the Crossroads – Translating Science into Action”, the best way to think of energy balance is a dynamic process. Energy intake and energy expenditure have an effect on each other and should not be looked at in isolation. Jakicic also makes clear how important it is to take a “2 prong approach to energy balance” to include both food and physical activity in the energy balance equation.
And it’s not just scientists with 30 years of experience in these areas. Government agencies agree that energy balance is the key to weight management and weight loss. According to the 2010 Dietary Guidelines for Americans, “Overweight and obesity will result from excess calorie intake and/or inadequate physical activity.”
2) All calories count and there are many factors that influence weight gain.
By promoting physical activity, no one is arguing that calories from food are not important or trying to “shift” focus away from food. The important thing to remember is that when it comes to weight management or weight loss, it’s the total calories that matters most. Our bodies need a certain amount of calories to complete day-to-day activities and exercise. Each person has unique calorie needs that depend on a number of factors, including height, weight, age, gender, and activity level. When we consume too many calories, the excess calories are stored as body fat. This can contribute to weight gain and, ultimately, health issues.
Martin Binks from Texas Tech University has tirelessly worked to show that obesity is a complex issue that involve many different factors, none of which is solely responsible for negative health effects. However, there are some things that we can prioritize for optimal health. In recent interviews, Binks emphasizes that “good nutrition” and “healthy physical activity” are the best ways to combat weight gain and obesity. Further, he states that there is no one-size-fits-all diet, or magic bullet against obesity.
3) Skeptics of physical activity are fighting a battle that has already been won.
Including exercise to maintain or lose weight isn’t a new concept, but it seems we have to gear up for a new fight for physical activity every time the obesity blame game rears its head.
An abundance of science has proven that physical activity is a crucial component to weight loss and weight management. A recent study in The American Journal of Medicine looked specifically at the physical activity side of the equation and suggested that America’s collective weight gain has been due to a decrease in physical activity, rather than an increase in calorie intake.
Additional studies point to the same conclusion: Reducing obesity will require modifying both energy intake and energy expenditure and not simply focusing on either alone. In a study published in Obesity, Jakicic stated, “The addition of physical activity to a dietary intervention can result in improved weight loss compared to what is achieved through dietary modification alone.”
So put your gloves down and let’s end this calorie blame game. Science has already proven that physical activity HAS to part of the obesity solution. Body weight is a balancing act between how much we eat and drink, and how often and how much we move. Ignoring either of those factors in the obesity equation directly conflicts with the totality of science on this topic. Dr. James Hill and Dr. John Peters summarize this point nicely, “[There is] clear evidence that exercise mitigates weight gain produced by energy-dense diets. Want to see more evidence – just go to PubMed and search for exercise and weight gain prevention. There are over 2000 papers in the past 5 years, most showing positive results.”
The final score is: Science 2,000+, Everyone else 0. GAME OVER.