“…a general public health recommendation for weight reduction through dieting cannot be supported strongly with existing data.” – D.S. Weigle, University of Washington
Occasionally when people hear about The Smarter Science of Slim they react by saying something like: “To lose weight eat less and exercise more…bottom line. I eat whatever I want and stop at 1,400 calories per day…and I’ve lost 12 pounds. A professor ate nothing but Twinkies and lost a bunch of weight because he cut calories overall…etc.”
There’s no denying that starvation causes us to lose weight in the short term. However, short-term weight loss is not our goal. Long-term fat loss and improved health are our goals.
Let’s imagine a world where cutting calorie quantity is the key to long-term fat loss. Now let’s try an experiment. We’ll divide a group of people in half. We’ll feed one half 120 extra calories per day for eight years. What would happen? If weight was ruled by calorie quantity, the math is pretty easy. Multiply 120 extra calories per day times 365 days in a year, times eight years, and the total equals 350,400 extra calories. Take that sum and divide it by the 3,500 calories in a pound of body fat, and we can predict that these people will gain 100 pounds. The equation is easy, but unfortunately, it’s incorrect.
Let’s look at a real-life study: the $700 million Women’s Health Initiative. This study tracked nearly 49,000 women for eight years. Just like our experiment, the women in one group ate an average of 120 more calories a day than the other group. Remember, that adds up to 350,400 more calories. How many more pounds did the women who ate 350,400 more calories gain?
That is not a typo. Eating 350,400 more calories caused the women to gain an average of less than a pound. It seems that something is not quite right with counting calories to burn fat in the long term.
Quantity-focused fat loss theories incorrectly assume that taking less calories in, or exercising more calories off, forces us to burn body fat. That has been clinically proven to be false. It does not force us to burn body fat. It forces us to burn less calories. That is why dieters walk around tired and crabby all day. Their bodies and brains have slowed down.
“Disproportionately large declines in resting metabolism are seen in food-deprived men.”– R.E. Keesy, University of Wisconsin
When our body needs calories and none are around, it is forced to make a decision: Go through all the hassle of converting calories from body fat or just slow down on burning calories. Given the choice, slowing down wins. University of Wisconsin researcher R.E. Kessey puts it more academically: “Metabolism [is] sharply reduced when an organism falls into negative energy balance.”
What’s worse, if our body still thinks we’re starving even after it has slowed down, it burns muscle. Only after it starts burning muscle does it begin to burn fat. A lot less muscle and a little less fat today leads to a lot more fat tomorrow.
Bottom line: If we just eat less of our existing diet we will (in this order):
- Slow down our metabolism
- Burn a lot of muscle
- Burn a little fat
1 + 2 + 3 = short-term weight loss and long-term fat gain (via yoyo dieting).
Fortunately, researchers have revealed a way to speed-up our metabolism, while maintaining muscle and burning fat. I call it The Smarter Science of Slim.
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