The Shifting Science of Energy Expenditure & Why “Just Move More” Isn’t Always Enough
For decades, our understanding of how humans expend energy – and therefore, how weight is gained or lost – has been built on measurements that are now being questioned. While seemingly precise, early methods for calculating calorie consumption, dating back too the 1950s, were acknowledged even at the time as approximations. Yet, this understanding solidified over generations, becoming accepted as fact in textbooks, studies, and online resources. It took decades and advancements in technology to revisit these foundational assumptions.
the key to this re-evaluation lies in a more precise method of measurement utilizing specialized isotopes. Though, widespread adoption of this technique has been slow due to notable hurdles. The process is expensive, requiring substantial energy to produce the isotopes and refined analytical equipment to evaluate samples. Furthermore, the technology itself is relatively new, only reaching maturity within the last 20 years.
This ancient context explains why researchers previously relied on less accurate methods, and why questioning established data felt almost unthinkable. The scientific process is iterative; what is considered truth today can be refined or overturned tomorrow.
This realization has even prompted reflection on research practices. Studies examining energy expenditure in diverse populations, like the hadza hunter-gatherers, while valuable for understanding the breadth of human experience, could possibly have been conducted closer to home with similar results. The expense and logistical challenges of traveling the globe to study these populations were undertaken before the limitations of existing measurement techniques were fully understood.
Ultimately, the evolving science of energy expenditure highlights a crucial point: individual responses to diet and exercise vary. While a calorie deficit remains basic to weight loss, how that deficit is achieved is highly personal. Focusing on a dietary pattern rich in whole, unprocessed foods and minimizing heavily processed items is a solid starting point. But finding a sustainable approach that works for you is paramount.
