Chronic Dieting: the Third Pillar of the Obesity Crisis

The most striking result of a population obsessed with thinness and weight loss is how unsuccessful most people are at achieving the goal. The more energy used for exercise and dieting, the fatter the country becomes.  Miracle diets blanket airwaves, papers and websites.  Exercise routines and gym memberships move through one community after another.  And yet we just get fatter and fatter.  When 99% of people who diet end up gaining all the weight back and more, when exercise programs seem to have no impact on a sedentary population, it is time to go back to the drawing board.  The new food political writers vilify the food industry, itself incredibly lucrative and grossly under-regulated, but there is no proof that eliminating McDonald's and Coke will solve rampant obesity either.  In fact, the evidence shows that the health-conscious, disordered eating sub-population can still gain as much weight on Pirate's Booty as they can on Doritos because overeating and a sedentary lifestyle are only two of the three pillars the obesity crisis has been built on.  The last, paradoxical and ignored issue is dieting.

It's abundantly clear how overeating and lack of exercise can lead to weight gain, but the link between chronic undereating and weight gain is not obvious to the majority of the population.  The newest diet plan stationed alongside the tried and true, established programs constitute a bevy of healthful and hopeful alternatives to the frustrated masses longing to reach their goal weight.  The proponents for various diets rarely experience public questioning and are instead viewed as saviors for a population lacking willpower.  Our national obsession with thinness blinds us to the dangers of chronic dieting.  Just look at the parade of celebrities that the diet industry uses to lure us into their web.  As one television star loses weight, her success is charted by the company to prove the plan's effectiveness and induce people to follow its success.  But, inevitably, as the person begins to gain weight, she is succeeded by the next star as spokesperson.  Of course, the company quietly blames the person’s inability to follow the plan.  No one questions the plan itself.
To understand how dieting fuels the obesity crisis, it will help to return to the set point theory.  As a reminder, the body has a set range of weight, about 15% from top to bottom, within which it moves freely.  Homeostasis, the mechanism the body uses to maintain stability in a variety of functions necessary for life, applies to weight as well.  The central tool to maintain weight is metabolism, which represents a host of changes in the body to use energy, namely food, either more or less efficiently.  At first glance, the set point theory seems contradictory.  Overeating when a person is at the top of the weight range leads to a metabolism increase, decreased hunger and burning off energy.  In fact, a significant spike in eating over a period of weeks can increase metabolism sharply and curtail any further weight gain above the top of the range.  Why, then, if there is a built-in cap on weight gain do so many people become obese?  On the other hand, chronic undereating leads to a conservation of energy: metabolism slows down, hunger increases significantly and the body, when given any surplus, voraciously stores food as fat.  In addition, studies of evolutionary adaptation have shown that the tendency to survive lean times, such as the winter, is much stronger than the need to override times of plenty.  Practically, this means that periods of chronic starvation will trigger a strong, protective mechanism to expect coming famines and store food for the future even when the times of plenty follow.
It will come as no surprise that even the most overweight portion of the population spends a fair amount of time dieting.  The more overweight, the more drastic the diet.  In fact, many diets suggest intake of 50-75% of the food needed for a given day.  A few weeks with such low food intake will trigger a powerful homeostatic response from the body, which means initial swift weight loss, followed by a sharp metabolism slowing and voracious appetite.  After reviewing the set point theory, the overall effect of periods of chronic dieting are clear.  These periods of undereating bring about the adaptive response to famine and that undoubtedly means weight gain.  In fact, the most overweight who follow the most severe diets can then continue to gain weight past their set point because of their extreme dieting.
To understand this confusing link between undereating and weight gain better, it can be helpful to look at chronic anorexia.  One of the most confusing aspects of anorexia is the patient, ten or more years into her illness, who, despite continued food restriction, no longer is underweight.  The psychological toll on the patient is overwhelming: how can years of decreased food intake, which consistently produced a very low weight, suddenly stop working?  For the more rare patients who maintain very low weight, severe illness and death around age 30 is almost certain.  For those whose weight returns to the normal, or at least not emaciated, range, the answer lies again in the set point theory.  Built into their genetic make-up is the ability to severely curtail metabolism.  The drive to slow down energy use, increase hunger and store fat easily overpowers the drive of the eating disorder and causes enormous frustration and despair in the patient, even though it also enables them to survive.  The most confusing aspect for the general population to understand is that an anorexic patient of normal weight can still be as severely ill as the emaciated one.  The medical complications and psychological torment from years of restriction, even if the body maintains a more normal weight, are severe and lead to disability, illness and premature death.
The set point theory is old, established medical knowledge.  Why has this information been summarily ignored through the obesity crisis?  How has the medical community spent so much public capital on new, ineffective weight loss techniques?  Can't an obese population desperate for successful measures to stop the trend look at the basic scientific data for simple answers?  With effective measures like weight maintenance plans and with a critical examination of the diet industry, these changes seem well within our grasp.  Instead, there has been an explosion in weight loss television shows while the nation tolerates a large number of children attending fat camp.  The public forum ignores this third pillar in the obesity epidemic while searching for the enemy to explain away our problems.  Yes, the food and diet industries are largely responsible, but we refuse to acknowledge the truth.  We have to stop dieting and praying for a miracle cure and instead need to find our own maintenance meal plan.
In adults, this transition is complicated by years of chronic dieting.  Finding a maintenance plan also entails the process of normalizing metabolism, which can be challenging for someone searching for a quick fix. But nowhere is this more important than in children.  As promised in the last post, I will address how to apply the idea of a weight maintenance meal plan for kids and their parents.

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