CFS is caused by Leaky Gut as you might be aware and therefore fasting or limiting what you eat ie not taking protein or fat but taking important nutrients which contain no protein/fat or constituents that the immune system can react to should provide some help.

However this cannot go on indefinitely as the human body needs protein and other nutrients on a regular basis.

If you try it make sure that you get some magnesium which your body needs and will not cause an immune system reaction. Vitamin C and B vitamins providing you have a source which does not contain allergenic compounds. Powdered sources without any fillers or additions such as rice powder or anything like that might be okay.

In theory it should provide some small benefit and maybe allow you to know what it is like to be without CFS, but it cannot go on long!

Yes and it helps.
Allergens are usually animal proteins and processed fats. Raw diet will benefit you too.
CFS can be due to toxins, radiation, as pointed above - to auto-immune reactions, etc.

I had chronic fatigue. Over the last 5 years, I've fasted for more than 365 days, if you can believe it.

It's been almost 3 years since I've had a cold, flu, or any kind of infection.

(When I was first diagnosed with CF, I had 6 chronic infections, and constant colds and flu viruses- 4 to 6 a year).

Fasting is what actually got me out of CF.

But there was months of prep work first.

I had to have a super clean colon, after being constipated my whole life. Once I didn't 'go' for 10 days.

Then I had to get over hypoglycemia.

And most important, was to get my PH up to at least 6.8. When it was that high for me, I could fast for a couple days. (When I was diagnosed, I was 4.8).

My PH has been 7.2 for a year now, and I can fast for a week, no problem.

The only rules I follow are:

1. I never let myself get lower that 125 lbs (my bottom of my healthy BMI)

2. I never continue to fast if my PH drops below 7.2.

3. If I'm not hungry by lunch time, I turn it into a fast day.

4. My cycle is lined up with the moon (period on dark, ovulate on full).

After your period, hunger goes down so it is a great time to fast. But as the body preps for ovulation, hunger goes up, so I fast less.

My motto has always been to look for signals my body gives off. When fasting was difficult, it was not the right time to do it.

However, I still can't eat whatever I want. I still have leaky gut, or can give myself leaky gut by eating the wrong food.

Gluten and dairy will always be my enemies!