Page 150 - GTM-4-1

Global Translational Medicine

LETTER TO EDITOR
Comment to the manuscript “chronic positive

mass balance is the actual etiology of obesity: A
living review”

Nikolaos Theodorakis *
1,2
1 NT-CardioMetabolics, Clinic for Metabolism and Athletic Performance, Palaio Faliro, Greece
2 Department of Cardiology and Preventive Cardiology Outpatient Clinic, Amalia Fleming General
Hospital, Melissia, Greece

Dear Editor,
The perspective manuscript titled “Chronic positive mass balance is the actual etiology
of obesity: A living review” makes an important distinction between mass balance
and energy balance in obesity, emphasizing the role of nutrient mass in body weight
regulation. This is an insightful argument, as the physical mass of ingested nutrients is
1
directly linked to body mass changes. However, dismissing the energy balance theory as
fallacious oversimplifies the complex interplay between mass and energy in biological
systems.

Body weight regulation is fundamentally governed by the interconnected processes
of mass balance and energy balance, both of which must be understood within the
framework of thermodynamics. According to the First Law of Thermodynamics
(conservation of energy), energy in a closed system cannot be created or destroyed but
is instead transformed into various forms. In the human body, energy derived from
*Corresponding author: food is metabolized into usable energy (e.g., adenosine triphosphate [ATP]), heat, and
Nikolaos Theodorakis
(n.theodorakis@flemig-hospital.gr) metabolic byproducts (e.g., CO , water, urea). Simultaneously, the Law of Conservation
2
of Mass governs nutrient flow, with body mass changes reflecting the net balance of
Citation: Theodorakis N. Comment
to the manuscript “chronic positive ingested, metabolized, stored, or excreted nutrients.
mass balance is the actual etiology Metabolism transforms nutrients into usable energy (e.g., ATP, guanosine
of obesity: A living review”. Global
Transl Med. 2025:4(1):142-143. triphosphate), “waste” energy (heat), and byproducts (e.g., CO , water, urea, uric acid).
2
doi: 10.36922/gtm.8079 These metabolic processes, which are influenced and regulated by multiple factors (e.g.,
Received: December 19, 2024 genetics, lifestyle, hormones), determine the fate of nutrients, which may be:
• Converted into usable energy (e.g., ATP) for immediate utilization in cellular
Accepted: January 10, 2025
functions (e.g., Na /K pump activity)
+
+
Published online: March 20, 2025 • Stored as fat or lean tissue (a process that also requires ATP utilization)
Copyright: © 2025 Author(s). • Dissipated as heat (e.g., via uncoupling of oxidative phosphorylation), or
This is an Open-Access article • Excreted as metabolic byproducts.
distributed under the terms of the
Creative Commons Attribution While the manuscript correctly identifies limitations in the rigid application of energy
License, permitting distribution,
and reproduction in any medium, balance models – such as their inability to account for the effects of macronutrient
provided the original work is distribution on body composition – its assertion that energy balance has no impact
properly cited. on body mass is scientifically inaccurate. A positive energy balance drives fat storage,
Publisher’s Note: AccScience increasing body mass, whereas a caloric deficit mobilizes stored fat, reducing body mass.
Publishing remains neutral with Energy balance and mass balance are not mutually exclusive but rather complementary
regard to jurisdictional claims in
published maps and institutional and interdependent. Neglecting this interrelationship misrepresents physiological
affiliations. reality. However, it is important to acknowledge that traditional energy balance models,

Volume 4 Issue 1 (2025) 142 doi: 10.36922/gtm.8079