Dieting: Success and Failure (Part 3)

Weight loss is intimately tied to eating behavior, and by behavior, I mean the conscious decisions made daily to either eat or not eat and what drives those decisions. Ignoring that behavior is the emotional equivalent of skipping work or school every other day just because it bores you. Intelligent people have an amazing capacity to commit to a behavior if it serves a greater purpose; however, that purpose and behavior need to be readily identified or else we rely upon reflex physiologic action to save us from ourselves. Not sleeping results in fatigue and eventual spontaneous loss of consciousness to accomplish sleep. Over-eating has no physiologic equivalent that signals us or identifies that too many calories have been consumed. Taking an evolutionary point of view, we evolved in a landscape of scarce resources and can over-consume at will as a survival feature. We are generally wary of heights because falling will kill us. We take large bodies of water quite seriously if we can’t swim. And a charging mastodon elicits an autonomic response to enable rapid response; again, so we can save ourselves. But over-eating food never evolved over the time frame molding our DNA in the equation describing survival. Thus, contemplating and intellectualizing eating behavior is all we have.

Politics describes the art and science of governing a population. The power and authority to make changes and control the behavior of the population is either top-down or bottom-up; or in the case of western-style democracy, a little of both. The president wields authority over the population for a short time and if the decisions and direction he takes the country is contrary to popular trends and beliefs, the bum is ousted at the next election. The same can be said for local and national politicians. If they bring home the pork, they usually get re-elected. Translating that style of government to the physiology of fat accumulation, as the lowly fat cells (or adipocytes as the histologists will declare) accumulate more and more triglyceride (storage form of fat), expanding from their usual 70 micrometers to nearly 130 micrometers, they revolt! “That’s it, we’re packed in here like rats on a tramp freighter and we just keep getting more. Throw the bums out!” The bums in this case would be us, as our overeating behavior continues. But as you can imagine and based upon the automatic function of the adipocytes, they live in a totalitarian political system. They don’t have a choice as to the amount or caloric density of the food we eat. They have no voice in their government and the decisions you and I make regarding daily food intake. And there is no feedback system signaling our brains that our fat stores are reaching critical mass, that our adipocytes are reaching 130 micrometers in diameter, and we need to cut back on food intake. Thus, their cries of revolt go unheard.

Rarely in the annals of cellular physiology and biochemistry has a line of cells revolted. They may wear out from overuse or toxic attack, but the top-down style of governance is the dominant biological theme. As described above, the lowly adipocytes are members of a typical totalitarian style of government—they simply do as told until they die, systematically performing the body’s bidding as the holders of excess energy. As energy intake in the form of foods increases, the adipocytes act like little energy tanks, storing any excess food energy until there comes a time (usually at night or between meals) where a very small amount of the fat will be needed and called upon to be used for energy. Accordingly, the flow of energy directly after eating a meal usually moves in the following general direction:

Food Consumed ----------> Make Up Energy Deficits

Food consumed is used to make up for lost glycogen stores, used for immediate energy needs, with the remaining shunted off to be stored in adipocytes as triglyceride. As the time between meals increases, the immediate energy derived from the prior meal is used up until a point in the fasting period when the storage fat from the adipocytes is recovered. That recovery process offers energy to the system and continues until the next meal is consumed. As the next meal is consumed, the flow of energy from adipose storage sites is shut off and the energy of the meal is utilized once again makes up energy deficits and begins the entire process over again. Again, any residual food energy is added to the adipocytes in the form of triglyceride.

Energy Excess ------------> Storage of Excess Energy in Adipose


That simple scheme describes in very broad brushstrokes the continuous cycling of energy in and out of adipose tissue. For fear of being redundant, fat cells store fat, which is later burned or metabolized by the body to derive useful energy.

Eating behavior and food choices are the input we add to the above equation or subtract from it. Attending too many business luncheons or dinners out or potlucks, results in adding triglyceride to adipose tissue to store the excess energy. Skipping some of those events or the foods present, will result in a relative energy deficit and energy moves out of the adipose tissue to be used to make up the deficit. There’s no metabolic magic or food calorie voodoo in the above scheme. And although I respect obesity researchers and geneticists, the accumulation of excess energy is not in any way a genetic aberration. An example would be the Pima Indians, a native Arizona tribe living and surviving in a very harsh environment around the Salt River. Traditionally the tribal members ranged over, in some cases, hundreds of miles to access adequate calories to survive. That evolutionalry pressure and the scarcity of calories, translates today (in times of food excess) to rates of obesity in the 80% range.