Does More Energy In And Out Make It Easier To Maintain Energy Balance?Monday, June 23, 2014
From every thing we know about obesity, the simplistic model of energy-in-energy-out (or Eat-Less-Move-More) approach to managing weight has not led us to any meaningful advances in obesity management. The number of people who can successfully manage their weight by this approach in the long-term is so minuscule, that every “success story” is considered “newsworthy”.
Now, a provocative paper by Gregory Hand and Steven Blair, published in US Endocrinology, suggests that what matters for good health is the amount of energy flowing through the system rather than the state of energy balance.
“Recent findings suggest that a high energy flux, maintained by increasing energy expenditure, can improve an individual’s metabolic profile without changing weight.”
This, essentially, is a fancy way of saying, that simply moving more calories through your body by burning more calories (even if you instantly eat them back) benefits the organism irrespective of any impact this may have on body weight – or that exercise is good for you even if you do not lose weight.
Anyone familiar with Steven Blair’s work (fat and fit is better than skinny and unfit) – will recognize the theme – but couching it in a concept of energy flux is a novel and interesting spin to this idea.
Apart from providing a theoretical model for how exercise may benefit you even if you don’t lose any weight doing it, the model may also have implications for weight management.
“The significance of the model of energy regulation is twofold: First, the model suggests that energy balance, and maintaining a stable weight is more easily achieved at a high energy flux. Second, a high energy flux can be achieved by matching a high energy intake with equivalent high energy expenditure, or by increasing energy stores (gaining weight). Of note is that these two characteristics of the model suggest that the biological system was designed to maintain a high energy flux, and increasing energy stores is a quite viable mechanism to achieve this level of energetics. An extensive body of research indicates that multiple and redundant mechanisms regulate the ‘drive’ for energy intake. The high energy flux is attained by matching the intake with expenditure and/or a change in energy storage. Weight gain is consistent with high energy flux combined with low energy expenditure, and it follows that attempting to achieve energy balance at a low energy flux (sedentary behavior combined with food restriction) is not a long-term strategy for weight maintenance.”
The biological question that pops into my mind of course is as to how exactly the body would sense this “flux”. While it is easy to see how the body would sense energy stores (e.g. through hormonal signals such as leptin), it is not clear how the body would monitor flux (after all, to regulate something, it needs to be measured).
This is not something that the authors delve into, thus leaving a somewhat unsatisfying gap in what otherwise makes for an interesting hypothesis.