Is this man seven feet tall because he eats too much? Did he just forget to count his calories? Hardly. Far more likely he’s got an excess of growth hormone, handing him a possible career as a basketball star.

So why do we assume that people with obesity, people who grow horizontally, just eat too much? They too might have an hormonal issue. Too much fat-storing insulin, perhaps?

Credits

My friend Fred Hahn just posted this picture and argument on his blog. And of course the argument is Gary Taubes 101. Still worth repeating though.

Less carbs, less insulin

Is “eat less and run more” really the only thing you need to know in order to lose weight?

Why is it then that most people lose weight on a LCHF diet, even when eating until satisfied? And this without even any increase in exercise? To think that this should be so controversial!

The best explanation, in a simplified version, looks like this:

Carbohydrates – > insulin – > obesity

Thus more carbohydrates lead to more insulin which leads to more fat accumulation. With more details this can be written as follows:

Too many (bad) carbohydrates – > pathologically high insulin levels – > obesity

What constitutes “too many” varies from person to person depending on sensitivity and activity level (how much carbs you burn). Intensely exercising young men can often tolerate a fair amount of carbs, while heavily overweight older diabetics can only tolerate minimal amounts without problems.

The opposite is the following:

Less carbs – > lower insulin levels – > loss of excess fat

Insulin is a fat storing hormone. And the easiest way to increase your insulin levels is to eat more carbohydrates. The easiest way to lower insulin levels is to eat fewer carbohydrates.

This seems very straight forward. But some are still adamant opponents. Without being able to come up with any better explanation as to why a low-carbohydrate diet works (it does) they still don’t want to accept this explanation. They come up with all kinds of objections. Some don’t even want to recognize the most basic, that carbohydrates increase insulin levels or that a low-carb diet lowers insulin levels.

Their complicated objections don’t matter much in reality. The truth is clear in study after study on humans. Insulin levels are much higher when you eat a lot of carbohydrates and lower on a low-carb diet. The figure above (from Boden et al.) is one example.

Here are some more: Continue Reading →

Is too much insulin the cause of common obesity? Yes, most likely.

Here’s another embarrassing high-profile study for all insulin deniers out there: Rats genetically modified to secrete less insulin from their pancreas stay slim even on a diet that makes other rats fat. Apart from the pancreatic insulin there was no difference between the slim (low insulin) and the fat (high insulin) rats.

The researchers, publishing the study in the high-impact journal Cell Metabolism, conclude that too much fat-storing insulin is a necessary cause of common diet-induced obesity (press release).

In humans the main cause of elevated insulin is eating too much junk carbohydrates. So it’s no coincidence that low carb diets consistently outperform other diets for weight loss.

It’s the insulin, stupid.

Earlier: The #1 Cause of Obesity: Insulin