Dietary Restraint and Cortisol Levels – Research Review

I don’t think I’ve done a research review in a while and even though I imagine some visitors to the site may be getting tired of topics related to the book I’m working on, well, that’s what I’m currently working on so it’s kind of at the top of my mind right now.

Today, I want to do a research review but for various reasons, mainly the abstract being too long to paste, I want to do it a little bit differently. The paper I want to look at is titled

McLean JA et. al. Cognitive dietary restraint is associated with higher urinary cortisol excretion in healthy premenopausal women. Am J Clin Nutr. 2001 Jan;73(1):7-12. And you can get the free full text here.


I imagine most visitors to my site are familiar with the hormone cortisol, even if many aren’t quite clear on what it does. Cortisol is often thought of as a “bad” hormone but this is too simplistic; what cortisol does in the body depends on a host of factors. The primary of these is whether it is released in a pulsatile and acute fashion (basically small pulses) or is elevated chronically. The first situation tends to be adaptive, the second tends to cause problems (for more details check out my still favorite book Why Zebras Don’t Get Ulcers by Robert Sapolsky).

So while acute pulses of cortisol help to mobilize fat, stimulate immune system function and improve memory, chronically elevated levels of cortisol may cause fat storage (especially in the face of high insulin), depress immune system function and harm memory. Basically, acute increases (that go down afterwards) are good, chronic increases (from chronic stress) are bad.