Lifestyle Blog

3500 Calorie Rule?


by Scott Silveira, MS, RCEP
Exercise Physiologist at California Health & Longevity Institute

There are a lot of misconceptions about the infamous 3500 Calorie Rule. The rule states that, a pound of fat stores 3500 calories and therefore, in order to lose one pound of body fat a 3500 calorie deficit must be achieved by diet or exercise. The flaw is that this rule assumes weight loss is a linear function, which is not the case. In actuality, weight loss resembles more of a hyperbola than a straight line and will eventually reach a steady state.

Dr. Keven Hall, a biophysicist at the National Institute of Health, undertook the task of creating a mathematical model that accurately simulates weight loss called the Body Weight Planner. His works has been validated across a number of populations and his equations have even been published in The Lancet, a reputable source for scientific studies. Using this tool, you can enter your personal demographics, desired body weight, and time frame, and the system will calculate the energy intake and expenditure necessary to accomplish your goal. For even greater precision you may input metrics like Resting Metabolic Rate, Body Composition, and Diet Composition.

Once you have your formula, the next step is measuring total energy expenditure to ensure you are on track. Fortunately, this tasks has become easier with wearable devices like FitBit or Apple Watches. For advanced platforms you may also work with an Exercise Physiologist to take advantage of the real time data these system can produce and apply it to programs like Fit Four All Seasons.

The other component is clearly dietary. While there are also many dietary tracking apps, they typically cause more stress factors than slimming factors. To take full advantage of the Body Weight Planner, consult a Registered Dietitian who can help you make sense of historical data and to make adjustments moving forward.