By saying that you get fat because you overeat is what scientists call a ‘cause and effect’ statement: Overeating causes fat. Unfortunately, the true cause and effect are reversed in that statement. The truth instead is: Getting fat causes overeating. Here is why.

Some of the research that I discovered for my Fat Loss Biology book (linked below) may come as a big surprise to you. The incorrect statement that you get fat because you overeat might be the biggest surprise of all.

Cause and Effect of Getting Fat

The true cause and effect are reversed in that statement. The truth instead is: Getting fat causes overeating. One of the interesting details that I uncovered is that obesity researchers have known this for decades.

The latest book by Gary Taubes, Why We Get Fat and What to Do About It, provides an extensive explanation about the cause and effect of getting fat. The key modern studies that show we overeat because we are getting fat, not the commonly believed opposite, began at the University of Massachusetts in the early 1970s, in the laboratory of Professor Gary Wade.

Here is what he discovered in female rats whose ovaries had been removed:

• When they were allowed free access to food, they would eat voraciously and quickly become obese. (This would seem to confirm the dogma that eating too much leads to obesity.)
• When they were placed on a strict diet after surgery – having access to only the amount of food that they would have consumed had they never had the surgery – they got just as fat just as quickly. (The conclusion from this experiment is that they didn’t get fat because they ate too much. After all, they didn’t have access to enough food to overeat. They got fat anyway.)
• Rats whose ovaries were removed and were on a restricted diet also became sedentary. They only moved around when going after their food.

Removing ovaries, of course, results in removing the main source of estrogen. Could this be the driving force behind their getting fat and slothful? Here is what Prof. Wade found out:

• When they were injected with estrogen after surgery, they did not eat voraciously, even with free access to food, and they did not become obese or slothful.

What these experiments show is that obesity is caused by an abnormal fat metabolism, in this case one induced by a loss of estrogen. The same thing happens in women who have the same surgery (removal of ovaries) or who go into menopause.

The main point of this explanation is that abnormal fat metabolism causes obesity, not overeating. Many factors can cause abnormal fat metabolism, not just loss of estrogen. After all, men and women both get fat. Other hormones can be involved. Not everyone responds to hormonal changes in the same way.

THE LESSON

You do not get fat because you overeat. You overeat because you are getting fat.

Take a look at the other topics that I discovered about the real biology of fat metabolism here in my book at FatLossBiology.com. You can see the entire table of contents there to get an idea of what I mean.

All the best in fat metabolism,

Dr. D