Possibly important for LW: He believes that very low carb diets + hard exercise with insufficient recovery + fasting all increase stress hormones, and can lead to exhaustion that takes a lot of time and work to cure, and that people don't necessarily get a lot of warning before they're in trouble.

In general this seems accurate but I request clarification regarding the 'hard exercise' claim. The word 'hard' in that context sets off warning bells. While either suitably extreme instantiation of 'hard' or a tautological instantiation of 'insufficient recovery' could make this claim denotatively true the connotations are something to be wary of. In particular I would like to assert the following claims and in so doing invite disagreement if the advice from your source happens to contradict them:

• High intensity exercise is better than low intensity exercise in terms of effect on stress hormones. For a given degree of physiological distress and fatigue induced better stress hormone results come from high intensity exercise than low intensity exercise.
• For the prevention of overtraining---the state where recovery is insufficient to the demands of exercise---an often effective solution is to reduce the amount of low intensity exercise and replace it with high intensity exercise. Obviously there will be less exercise as measured by time but more by measures of physical adaptation.
• Except in extreme cases the effect of high intensity exercise on stress hormones is decidedly positive. Not only does such exertion reduce the level of stress hormones (and stress) in the body on average it also makes the body better able to resist the effects of stress. In particular the new neurons produced due to high intensity exercise are less vulnerable to destruction via chronic or acute stress. Many rats died in the discovery of this phenomenon.

I don't wish to criticise or reject your source. Pardon me if I am excessively wary of the wording. Unless his advice contradicts the above claims, what you have conveyed of his lessons thus far indicates that he is worth listening to. I'll add that his observation about fasting matches my research on the subject. Those that eat irregularly can in general improve their cortisol levels by consuming protein in the morning---that seems to be a fairly consistent finding.

Thanks NancyLebovitz.

The more I learn about human metabolism, the more I realize how complex it is. And because of that, I am more skeptical of simple, broad claims, that aren't backed up by solid research.