In my post yesterday, I wrote the following:
The problem with low-carb diets is the following: The body releases insulin to process the amino acids in proteins. When insulin rises, the body needs to raise blood sugar to avoid hypoglycemia. If there’s no glycogen (sugar) stored in the liver cortisol is released instead, which increases blood sugar. Cortisol suppresses thyroid function and immune function, and lowers metabolism.
I was paraphrasing what I heard Ray Peat say in an interview about sugar and carbohydrates.
But over the last 24 hours I’ve been thinking about this. If this is the case, then why do so many people have success losing weight with low carb diets? I decided to go back and listen again to make sure I really understood what he was saying about cortisol being released when you don’t eat carbs. Here’s an actual transcript:
Several of the amino acids in proteins are powerful insulin stimulants, and when you eat protein by itself, you stimulate insulin secretion which is needed to metabolize the amino acids. But in reaction to the insulin, your liver has to put out glucose to keep your blood sugar going so your brain and blood cells and kidneys and so on can keep working. And if your liver is somewhat low on glycogen, then every time you eat protein and have an insulin secretion, your body secretes a compensating amount of cortisol to bring your blood sugar back up. But the cortisol brings your blood sugar up at the expense of protein.
[…] The first tissues that cortisol breaks down are the thymus gland and other immune cells and the muscles and if you eat lots of protein in spite of the high cortisol, you can keep your balance so you are replacing your muscles and thymus gland but you are running on a constantly high cortisol secretion.
Yeah, I heard him right. So given this, how come people are able to lose weight on low-carb diets? Is he saying that weight loss from low-carbing is all loss of lean tissue? How about people who lose LOTS of weight eating low carb?
He goes on to say:
[…] I’ve seen that doctors simply neglect to measure hormones that were related to blood sugar when they would prescribe insulin, calling a person a diabetic, they said they needed to take insulin the rest of their life. But, having some of these people test their cortisol, we saw that very many of these so-called diabetics just had very high cortisol. Sugar happens to be the best thing for lowering cortisol to normal, and since high cortisol gives the impression of diabetes, causing high blood sugar, you get the unexpected effect of when you eat sugar you lower the cortisol, and some of these people had a very quick recovery from their so-called diabetes.
This explains why a lot of low-carbers have what they like to call “Physiological insulin resistance,” (as opposed to “Pathological Insulin Resistance”, I think). It’s not real insulin resistance – it’s just the effect of high cortisol secondary to low-carb intake.
Which leads me to another question – when I was low carb, how come my cortisol didn’t test high? (Update: The answer to this question is in the comments of this post.)