Disclaimer: I just want to precede this message with a disclaimer that this work is on-going and is early stage. It represents my thoughts at the moment more than any hard evidence. Hopefully in the next week or so I'll be able to polish it up and remove this disclaimer.

Most of us have varying degrees of brain fog. For me I've pretty much woken up "hung over" every day for the last 3 years or so. On a typical day I would spend the morning in a stupor and only gain my senses around afternoon time. I thought it was the candida producing acetaldehyde (the breakdown product of alcohol) which was causing this.
Big mistake.

2 things should have alerted me:
1. I was eating a low grain diet - so the candida had nothing to ferment
2. If it was acetaldehyde poisoning which was causing the brain fog, why would I only very rarely feel the effects of the alcohol??

It turns out (I believe) that my brain fog was caused by hyperammonemia (too much ammonia).

I started taking the amino acid Histidine a couple of weeks ago and immediately noticed the following:
1. I would sleep more deeply
2. I would wake up with a clear head and not hungover
3. I would get borborygmia (stomach rumblings). Lack of borborygmia is one of the symptoms of candida I've had for the longest time.
4. Associated with 3 I felt I was producing more stomach acid (though probably still not enough).

Histidine is most famous for being the precursor to Histamine in the body which most people know is involved in allergic reactions, but Histadine has many functions unrelated to this:

• Histidine is a vital component of gastric juices (this is the original reason I took it)
• Histidine is associated with delta level sleep (this is the level of sleep in which the body repairs itself)
• Histidine is used to regulate: Copper, Zinc, Iron, Manganese, Molbdenum.
• Histidine binds with heavy metals.
• Cutler: Elevated histidine in urine is indicative of mercury/copper intoxication.
• Histidine deficiency can be caused by a Folate deficiency (which results in excess uriny output of histidine).

The Urea cycle is a series of 5 liver enzymes that rid the body of ammonia (by converting it into urea) and is used to metabolise amino acids (the urea is then transported to the kidneys where it is excreted in urine).

So basically my Urea cycle isn't working properly resulting in too much ammonia = brain fog. There are a number of defects which can occur with the Urea cycle.

For example, Autism presenting in adulthood (japan) has been linked to OTC deficiency. OTC=Ornithine transcarbamylase is one of the enzymes involved in the Urea cycle, and is actually the most common defect of the urea cycle. Low levels of OTC lead to hyperammonemia. Thats brain fog to you and me. Incidentally OTC can also be damaged by mercury.

Somehow histidine seems to be counteracting all this. Now acetaldehyde is an exogenous toxin not normally produced by the body. As such there is a specific detoxification pathway (i.e. acetaldehyde dehyrogenase), and there are few things which will speed this up (molybdenum being one of the few). However Ammonia is an exogenous toxin - it is something all of us produce all the time. So the fact that Histidine to a large extent counteracts my brain-fog (especially early morning fog) tells me that the brain-fog is more likely to be caused by urea-cycle dysfuntion and not by acetaldehyde.

So whats my point? Its certainly not to get people to rush out and buy histidine.

My point is that brain fog is not caused by acetaldehyde, but instead it is caused by a urea-cycle defect resulting in too much ammonia accumulating in the tissues/brain.

My recommendation is to have an amino acid profile done and to see which ones you are deficient in, and if you have persistent brain fog (even when on a low fermentable carbs candida diet) to get your urea cycle checked out.

JV.