First of all L-Lactate and D-Lactate convert back and fourth to each other in the body. D-Lactate acidosis is real and can be induced by ingesting lots of lactic acid producing probiotics. There are two components to CFS IMO. Endocrine abnormalities and autotoxemia from infection (unwanted gut flora). Subclinical hypothyroidism IMO causes the immune dysfunction which sets up the autotoxemia and overall decline of every cell. I take 300mcg of T4 a day. Doctors today do not use enough t4. If you can't handle the side effects of T4 you need a beta blocker, but probably all of you could use more t4. I have tried t3 and it has such a ridiculously short half life that it just burns up whatever cortisol our weak adrenals can muster and leaves me at least more tired 30 minutes after the initial boost of energy I get, no matter what the dose. Iodine replacement is needed as well as selenium and Vitamin A.