Energy Balance is a Physiologically Controlled Process
A study by Stephen O’Rahilly and I. Sadaf Farooqi reflects this possibility. They say, “obesity (in humans) is a heritable neurobehavioral disorder that is highly sensitive to environmental conditions. ”
Dieting, undereating, starvation, excess food availability, inadequate quality food availability, etc. are the environmental conditions we’re talking about here.
O’Rahilly and Farooqi go on to observe, “Energy balance is a physiologically controlled process. If genetic variation influences body fat stores, then it must do so through biological and not ‘metaphysical’ [abstract] processes. A body of work stretching over nearly 70 years has clearly demonstrated that energy balance in mammals is a homeostatically [equilibrium-regulated] process involving a dialogue between the sites of long-term energy stores, i.e., adipose tissue, and the brain, which is the organ that coordinates food intake and related behaviors and is the central control of
So, these scientists have concluded that energy balance in bears as well as humans, both mammals, is biochemically (internally) controlled. Therefore, the overeating, fat storage and use of fat during the feast or famine cycle and the hibernation cycle is a function of biology—and not caused by food addiction or other emotional or psychological problems. Bears and people overeat because they need to overeat. Their survival depends on it.
DO BEARS EXHIBIT ADAPTIVE CYCLICAL OBESITY SIMILAR TO THE FEAST OR FAMINE CYCLE Photo Gallery
But Bears Aren’t People
You’re probably wondering if this bears illustration is really relevant. People are much more complicated than bears so you can’t really make a valid comparison, right? Human beings experience a whole gamut of influences that animals clearly don’t. So, doesn’t it seem logical that people with weight problems would struggle with a lot of things that bears don’t? Of courses they do. But going back to physiology, underneath all these differences, humans have profound things in common with other mammals. Regarding food, bears and people have similar physiological sensitivities to the environmental food supply, and the same drive to survive—basically the same adaptive potential in this vital area. This is how those two things translate into what we have in common with bears:
• Bears and humans use up stored fat when food is scarce or unavailable. Hibernation and diets are both forms of food scarcity or unavailability.
• Bears and humans eventually overeat and store fat with the cyclic abundant food supply. This is expressed in hyperphasia in bears and rebound overeating in dieters.
• Both bears and humans again use up fat that has been stored when once more food becomes scarce. This is the next cycle of hibernation in bears and the next diet for dieters.
This feast or famine pattern reflects a yearly hibernation famine for bears and a periodic diet cycle for people—sometimes it’s a year, sometimes a few months. Bears experience famine yearly and dieters endure famines as long as they can tolerate the food restriction.
The connection between lipoprotein lipase, research on the psychological make up of overweight people, the behavior modification studies and post-diet weight rebound, point strongly in the direction of physiology to explain weight problems. In fact, some obesity research is beginning to go in the direction of physiology rather than psychology. But, the superstitions about fat and weight gain and obesity are rampant. There is still so much uncertainty about obesity even though we have a great deal of evidence that we are barking up the wrong tree. It seems that we only get more confused as new ideas come along. I interviewed the head of an obesity research department at a university and I shared my observation that there is a link between dieting and weight rebound. He laughed and said, “You actually think dieting has something to do with over eating?” I said I did. He laughed again. He was quite fat.