Two articles poo-pooing on "adrenal fatigue":
Glenn Beck: Adrenal Fatigue
Adrenal Fatigue and Starvation
I'd rather not take a side on it. I just don't know enough. But here is my experience:
Back when I was new to being a trainer and coach, I was also doing the WellnessFX testing. My first test went smashingly, I learned a lot of interesting information about what my body was missing and how I could eat to fix it. Actually, I learned that my lifestyle had me doing a lot of things right.
We (me and the ManFriend) used this as a baseline to then start on our Paleo/Primal eating journey. We even hired a chef to cook our food for the week to make sure there was no chance of slipping.
I was also limiting my carbs at the time because I was trying to stay at 165lbs for weightlifting, and then I just knew that it was about limiting "bad calories". Bad calories were high glycemic index carbs and anything Robb Wolf called bad.
Then the second WellnessFX testing showed me as basically healthy, except for some markers of stress and potentially high cortisol.
"Well, I have been feeling anxious lately. And I don't sleep well," I told the nutritional counselor.
"It looks like your diet here is really good. But you might be suffering from adrenal fatigue. Here are some suggestions and supplements I would have you take to treat that."
So I listened and tried and told myself things were getting better.
They weren't really getting better. Once I stopped the whole Paleo thing, the random anxiety and feelings of panic definitely subsided. But I was still being restrictive in my eating because I, again, just knew that certain things were "good" and certain things were "bad."
When I decided that I should stop trying to be 165 lbs for weightlifting and just get up to 180 lbs (the top of the middle weight class for strongwoman) I had more good effects. But, again, I was still being super selective about my food (particularly my carbs) because I just knew that carbs would make the bloat and inflammation come on.
Then I got tired of having a meh physique, and hired a nutrition coach to help me out. First thing? Up the carbs A LOT. Double what I was doing (160g/day to 299g/day). And in the first two weeks I lost two inches around my waist without losing any weight. Why? As she explained, when you restrict carbs too much, especially for people who train hard, you're going to see an increase in cortisol, which is a culprit for water retention and fat accumulation
(See also: lack of sleep, cortisol, and body fat.)
I would say that those experiences that led to a "diagnosis" of adrenal fatigue are mostly gone (constant sleepiness, needs for naps, random panic or anxiety). I still have anxiety around waking up when I set my alarm and get poor sleep on those nights, but now I fall asleep faster and wake up later in the night. I don't feel the need for midday naps like I did from earlier in the year. I even try to nap and I get antsy.
So is adrenal fatigue a thing? I don't know. But I'm pretty sure I didn't have it, and like many self diagnoses, is probably way over blown from what actually occurs.