A low ammonia diet may be necessary when treating certain single nucleotide polymorphisms (SNPS). Ammonia is created in the body when bacteria break down food in the intestines, releasing ammonia into the body. Those that are particularly affected by ammonia are SUOX, NOS, A1298 and CBS. These snps affect certain metabolic pathways and can also reduce BH4 levels. It is also important to increase BH4 levels, as well as reduce ammonia levels in the body.
Normally, BH4 is used to recycle and detoxify ammonia, but when it is reduced and normal or elevated levels of ammonia are present, these can cause a variety of health problems. These health problems can range from brain fog, fatigue, muscle fatigue/weakness, among many others.
Symptoms of ammonia toxicity (which can affect people with low BH4 levels) can range from brain fog, language problems, lack of concentration, dark circles under the eyes, learning and memory problems, as well as food intolerances. (particularly proteins). In some rare cases, it may also be necessary for those who suffer from liver or kidney problems.
It can cause other mental/physical symptoms, as well as anxiety and depression. When there are lower levels of BH4, you will prioritize ammonia detoxification over other essential functions, such as producing neurotransmitters. Neurotransmitters can affect many functions in the body, such as mood, appetite, memory, and overall mental function.
To compensate for the reduced amount of protein in the diet, it may be necessary to supplement with amino acids to make up for the lack of amino acids from lower amounts of protein. There are certain foods that contain higher amounts of ammonia than others, a list of which can be found here: http://wholefoodcatalog.info/nutrient/ammonia/foods/high/
As can be seen from the list, it would be beneficial to follow a paleo template diet with a reduced amount of protein. To further make up for the reduced amounts of protein, it would help to increase the amount of carbs and fat as well.
Proper supplementation can also help, but it should be done by a well-trained health professional or well-versed in methylation and complex health issues. Finding help for people with mthfr, detoxification can be difficult, as many are unaware or know very little about treating these problems.
Addressing adrenal, thyroid, and GI health is also important when dealing with such complex health issues. I found this note particularly helpful, especially explaining ammonia issues and treatment goals when it comes to certain SNPS: https://www.facebook.com/notes/insight-naturopathy/mthfr-a1298c-polymorphism/385764944792649