Obesity and Exercise: Does Working Out Really Make Us Thinner?

Obesity and exercise are hot topics to debate. But how did we become so obsessed with going to the gym, counting calories, and watching our weight? What is the relationship between obesity and activity? Does working out "burn off" excess fat calories and lead us to be lean and healthy? Or does increasing your level of physical activity help nary a bit at controlling weight over the long term? And if so, why? What does the science tell us?

Our public health authorities assure us that calorie manipulation is the key to weight loss. Any diet that does not focus on calorie control is a "fad diet," according to mainstream nutritionists, who insist that the 1st law of thermodynamics compels us to accept this fundamental rule that calories "count." They also insist that, by restricting the number of calories we take in, and/or by burning off "extra" calories, we will lose fat.

The Lipophilia Hypothesis tells us that calories don't "matter" -- at least not in the way that we think they do. Exercise may yield health benefits. But working out won't make you thinner over the long term unless you fix whatever hormonal or metabolic imbalances have made you fat in the first place. In particular, the control of insulin is key. And restricting the amount of carbohydrates we eat, particularly the refined carbs, should help because these foods have incredibly insulinogenic effects.

Okay, so we have these two theories about obesity and exercise. One predicts that exercise should lead to weight loss. The other says that exercise won't really help and that what really matters is controlling the hormonal environment of the fat tissue.

So what can the evidence about obesity and exercise tell us?

1. Here is a great article on the subject: 'Why exercise won't make you thin' from Time Magazine.[1]

"'In general, for weight loss, exercise is pretty useless,' says Eric Ravussin, Chair in Diabetes and Metabolism at Louisiana State University and a prominent exercise researcher. Many recent studies have found that exercise isn't as important in helping people lose weight as you hear so regularly in gym advertisements or on shows like The Biggest Loser -- or for that matter, from magazines like this one. The basic problem is that while it is true that exercise burns calories and that you must burn calories to lose weight, exercise has another effect: it can stimulate hunger. That causes us to eat more, which in turn can negate the weight loss benefits we just accrued. Exercise, in other words isn't necessarily helping us lose weight. It may even be making it harder." (bold added)

This Time Magazine article is a chockfull of references to studies on obesity and exercise that show that exercise does not make us thinner. Of course, many obesity researchers use this evidence to argue that the key to losing weight must therefore be calorie restriction. They MUST make this argument because if both exercise and calorie restriction do not lead to weight loss, then the Caloric Balance Hypothesis implodes on itself. To survive, the Caloric Balance Hypothesis requires that either "Calories In" or "Calories Out" or both must be critical controls of our fat tissue. If exercise doesn't work, and if calorie restriction doesn't work, then the entire theory -- and all of its implications -- must be discarded!

Okay, so is there other evidence about obesity and exercise? Absolutely.

2. Check out this article (link below) published in the British magazine Telegraph in January of 2008: "Big Fat Lie."[2]

The author interviews science journalist Gary Taubes, who discusses the plethora of studies that show that exercise just doesn't work as a weight loss therapy.

3. If this article intrigues you, just wait until you check out Taubes' book, Good Calories Bad Calories -- in particular pages 259 to 269. Taubes analyzes the key research that's guided our beliefs about what constitutes a balanced diet.[3]

Taubes explains that we got the idea that exercise makes us thinner based primarily on the work of a single researcher, André Mayer, who -- unlike clinicians like endocrinologist Hugo Rony and Russell Wilder (both of whom supported ideas that validated the low carb diet theory) -- never had personally worked with obese patients.

Taubes walks us through how Mayer derived his hypothesis about obesity and exercise, and then he proceeds to pick apart of all of Mayer's arguments ruthlessly using powerful arguments and data.

In particular, Taubes discusses:

  • That "the association between reduced physical activity and obesity doesn't tell us what is cause and what is effect."
  • That since poor people are among the most obese and since poor people get more exercise than rich people, this should indicate that exercise won't make us thinner.
  • That even if exercise can help us burn calories, it also makes us hungry, which causes the body's homeostatic mechanisms to drive us to eat more calories.

4. Also see this article from the New York Times.

So where does all this leave us? If exercise doesn't lead to weight loss, and instead leads only to hunger; then the hypothesis that 'a calorie is a calorie' should be rejected, which would leave the alternative idea about obesity and exercise, Lipophilia, as the clear winner.

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1. Cloud, John. Why Exercise Won't Make You Thin Time Magazine online (Aug 9 2009).

2. Melissa Whitworth. Big Fat Lie Telegraph online (Jan 27 2008).

3. Taubes, Gary. "Good Calories, Bad Calories." pp 259-269. New York: Knopf (2007).

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