Hi
@JollyRoger,
There are a few (long) threads on here about keto diets. It certainly gained some more interest again recently with the discovery of PDH issues, I understand a well known patient/activist (Jennifer Brea) also advocated strongly for it. Some have found it intolerable due to poor fat metabolism, some tolerated it but didn't improve, others found it very helpful but only for a limited time.
Personally I've been in ketosis for 8 months and have found it to be hugely helpful. Before starting I had progressively worsened to mostly housebound and unable to function much for more than a couple of hours a day, becoming very symptomatic and having huge energy crashes every few hours. Within a week or two of starting the diet I was able to function much better. I could sit up at my desk and think clearly again, I could manage light mental work for long stretches, I could leave the house & cope with some slow exertion without onset of migraine, shortness of breath and exhaustion.
Whether my improvement had anything to do with PDH I do not know. I suspect that the dietary change helped with several other issues I have, which are not universal to the ME population - though I'd imagine are more common than most patients realise.
The first and most significant being reactive hypoglycemia, as recognised by the endocrinologist who put me on the ketogenic diet. If you have POTS/Dysautonomia as a major part of your ME/CFS then you should have a high suspicion of postprandial glycemic problems. It seems dumb to me now that I didn't realise I was crashing hard an hour or so after eating meals 3x times a day, especially so if I'd had a carb-loaded meal. It never crossed my mind, much like the problems maintaining orthostasis had presented for many years, as they both came on so insidiously. The keto diet really smooths out blood glucose fluctuations and banishes so many hypo symptoms & sleepiness caused by these fluctuations with a matter of days.
The second benefit I had from cutting carbs & restricting food types was the positive effect on controlling SIBO, which in turn seemed to be driving some sort of MCAS-like reactions to most foods - complete with another flavour of fatigue and other substantial symptoms.
Thirdly I wonder if the anti-inflammatory nature of the diet also plays a part more generally.
I think the take away message I'd want to impart would be if you have ME/CFS and any symptoms consistent with reactive/postprandial hypoglycemia I would definitely consider trialling the diet, especially if POTS/Dysautonomia is also present. 20+ years of ME/CFS here and it never occurred to myself or doctors at any point that carbs could be driving problems until they became very significantly disabling, more so than any other aspect of the illness.
Ryan