12/15/11

The Dangers of "Healthy Eating," Part I

Just walk through any main street, from the small country town to the big city, and it is evident that we have much, much more food than we could ever consume. The number of fast food outlets, convenience stores and supermarkets seems unlimited. The edible food waste of the First world could feed most, if not all, of the world's starving people.

But the larger realities don't change how each individual, still charged with feeding oneself, thinks about food. The now mundane choice, and for some the burden, of what to have for lunch among the wide options would have been a dream come true for humans through the ages. It is as if we have all become the wealthiest aristocrat with more food than we could ever consume, with every possible treat at our disposal. Yet this purported boondoggle turned out to be much more problematic than anyone could have guessed. Rather than creating a utopia, the world of plentiful food has left millions of people reeling without the ability to handle a seemingly basic fact of life, how to eat.
We are a species designed to live in a land with the natural ebb and flow of feast and famine, not in food heaven. A basic fact of human life for almost our entire existence, the worry of going hungry isn't relevant for an astounding number of people in modern life. The preponderance of food tempting our palate at every turn has completely perplexed our internal ability to regulate hunger and meals. Humans have been engineered to outlast famine and drought but have no clue what to do with an endless surplus. The newfangled coping mechanisms--ranging from arbitrary food rules to diets and, in more extreme cases, from eating disorders to Bariatric surgery--only highlight the futility of trying to outwit our fundamental instinct to eat to survive. But it is the least controversial and most widely accepted solution that confuses us the most. The next series of posts will address the effects of this insidious cultural innovation: the concept of "healthy eating."
In order to understand what's so ineffective about the concept of healthy eating, it helps to start with the current fascination with the human brain. The increasing knowledge about human's higher order functioning, such as consciousness and planning, mental constructs unique to people, has seeped into the mainstream. The unfortunate result is the expectation that people can think and reason their way out of any situation. When it comes to food, it is necessary to remember we have evolved from the same genetic line as apes and other mammals so the basest instincts apply.
Humans, like all animals, value survival of the species above all else. Enduring times of famine and drought was and still remains essential. Just as bears hibernate or squirrels store acorns for the winter months, people developed evolutionary adaptations, mainly an adjustable human metabolism and hunger drive, to weather more challenging circumstances. And that ability to survive, despite the creation of a world of plenty, trumps any intellectual means to manage food. Put simply, when it comes to food, basic drives override rational strategies. It is instructive to take a look at the basic biological reaction to times of need and times of plenty. An often used but misunderstood concept, metabolism, the utilization and dispensation of energy throughout the body, is the central tool to adjust to an ever-changing food supply.
A withering food supply triggers a cascade of physical changes: slowed non-essential body function, more efficient use of energy, steady breakdown of the body's energy stores and any extra food intake going directly to temporary storage. The swift transition in metabolism when times became lean is a key component to our longevity, otherwise humans would have become extinct many ages ago. The ability to survive famine is a trait deeply embedded in our genetic make-up. In other words, our bodies are built to survive starvation.
The same cannot be said about times of plentiful food. Those periods were, from an evolutionary perspective, mere blips in the calendar. The boom of a large food supply would never threaten humans with extinction so any adaptations are short-lived and limited in scope. In fact, these brief periods of plenty were, if anything, used to protect against the inevitable hungry times in the near future. Consequently, these were times of brief gorges while those more prone to restraint encouraged the tribe to consider external food storage, say for the upcoming winter, rather than rely solely on humans' internal ability to store energy.
After an extended period of overeating, the body will work hard to overcome the excess. Although the metabolic changes are the opposite of the starvation response, sped up metabolism and increased energy usage, the process is much less robust, and the body is willing to give up quickly and just store the energy as fat, fully expecting to need the backup shortly. 
Stay tuned for part II.

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