I have had chronic fatigue and, believe me, I know how it feels. I used to call it my crushing fatigue feeling. Not nice at all.
There are loads of different avenues to explore in chronic fatigue/ME cases. Some of the issues that have most commonly cropped up clinically in my experience have been:
Allergy and intolerance – it is amazing how a sensitivity to food, inhalant or something can completely drop you and no-one ever believes me but it turns up all the time. Note that chronic fatigue is one of the top gluten-related disorders (not just coeliac disease, but more usually CFS is a feature of non-coeliac gluten sensitivity). It turned out to be that in my own case. Just sayin.. Read more about GRDs here.
Adrenal fatigue. This is almost always a part of it. Check and correct. Read all about adrenal fatigue here.
Underactive thyroid. An obvious one to look at. Cold, tired, listless. No brainer. Check and correct.
Anaemia. Of course. Which leads onto…
Nutrient deficiency. I have often seen a lack of nutrients, especially in teenage cases which, when corrected, solved the whole problem. No nutrients = no energy. White spots on nails? Just had a growth spurt? Puberty kicked off? All vulnerabilities in my experience. There are many nutrients tests but, effectively, I find the red blood cell minerals, Vitamin D and fatty acid levels are most key. If all are low, probably malabsorbing. You can see all the Nutrient Tests here.
Then, there are the more in-depth things to check including viruses, parasites, liver and methylation issues etc, all of which you can read more about and test for on the shop site. Read the overviews in the relevant sections.
There is a fabulous resource here which might help. It is a pretty comprehensive rundown of testing and treatments involved in chronic fatigue. I can help you with almost any of the tests mentioned so do just ask if you need help. Check the Tests FAQ for how it all works.
There is also a brief but useful primer on Chronic Fatigue here from GreenMedInfo.
Finally, ACE Disorders, childhood or adult stress and trauma is showing up an awful lot as a key factor in why people develop what I term ‘hypersensitivity’ illnesses later down the line, usually in their 40s. These illnesses are where people have become sensitised to stressors more than normal, the amygdala in the brain is too-turned-up, if you like, and it causes real physical illness including food/chemical sensitivity, anxiety disorders, chronic fatigue, chronic pain and all manner of glandular and hormonal imbalances. Have a read of my factsheet on ACE Disorders and Trauma-Triggered Illness here and the Healing Plan where I wrote down how I got over my own illness.
Don’t be tempted to dismiss this like I did for several years. I know it sounds odd, but it is proving to be a real key for many so humour me and read it anyway and see what your score on the questionnaire is. If it’s not that: great; you can at least rule it out.
My advice, generally, would be to keep it simple and go through the main issues I’ve mentioned first before you get all complicated about it. I’ve learned over time that it is easy to miss the obvious and get bogged down in really complicated factors when actually the easy stuff corrected resolves most issues. It may be then that you can see the wood for the trees a bit and narrow down anything not corrected.
Good luck!