Study Shows Starved Overweight People Burn Less Fat Than Starved Thin People


In previous posts we reviewed research showing that eating less of a traditional diet and doing more traditional exercise does not effectively burn fat. Rather, it is effective at causing our metabolism to slow down and our muscles to be burned. In this post we’ll explore a study done at St. Joseph’s Hospital and Medical Center in Phoenix, Arizona, which shows that this “slow down, burn muscle, then burn fat” dynamic is intensified in heavy individuals.

In the study, researchers examined both heavy and thin people to see how their metabolisms behaved when they were given no calories. As expected, everyone slowed down. Because these people were on zero-calorie diets, everyone also burned some body fat, but here’s the kicker. Thin people burned off nearly 50% more body fat than heavy people.

Think about that for a second. Despite having more body fat, the heavy people burned less body fat. In the words of the researchers:

“…obese patients could not take advantage of their most abundant fat fuel sources but have to depend on the efficient use of…the breakdown products of body protein [muscle].”

That finding is depressing. The heavy people burned what relatively little muscle they had rather than burning the excess body fat they were drowning in. They needed to burn body fat, but did not burn body fat effectively.

But why?

Creating the need to burn body fat isn’t enough to burn body fat effectively. Our body must also have the ability to burn fat. The requirement for both the need and the ability to burn body fat is a very important point to understand, because at the root of chronic weight gain is our body’s inability to burn body fat effectively. This is why research J.M. Friedman at the Rockefeller University noted that there is “something metabolically different about [overweight] individuals results in obesity independent of their caloric intake.” He is referring to their inability to effectively burn fat despite how little they eat and how much they exercise.

In SANE I call the inability to burn fat a “clog” in our metabolism. Researchers at the Harvard Medical School call it “metabolic dysregulation.” And whether we call it being clogged or experiencing metabolic dysregulation, science shows that until we restore our ability to burn body fat, eating less of our existing diet and doing more of our existing exercise routine will primarily slow us down and burn muscle. Fiddling with the quantity of calories in or out does not create the ability to burn body fat. To do that we need to shift our focus to eating more—but higher-quality—food and doing less—but higher-quality—exercise.

Eating more high-quality food provides more nutrition while preventing overeating. This creates the need to burn body fat. Add less, but higher-quality exercise, and we activate clog-clearing hormones which restore our ability to burn body. And since we will eat as much high-quality food as we want while doing only ten to twenty minutes of high-quality exercise per week, we can keep this up permanently. That permanent need and ability to burn body fat is our proven path to long-term fat loss.


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