carnitine: not just choline to be avoided in tmau diet

This is a copy of today's post from mpdela.blogspot.com, I read her blog everyday for new information:

Tuesday, August 24, 2010

Carnitine : not just choline to be avoided in TMAU diet
Those interested in TMAU are very aware that choline is to be kept minimal in the disorder, since gut bacteria can metabolize the choline, with one resulting metabolite being trimethylamine (TMA). However it may be often overlooked that another compound that can result in TMA production is carnitine.



The 'avoidance' diet strategy for TMAU mainly involves :

1. Keeping anything that can result in TMA to a minimum
obvious examples :
Choline (remember this is an essential nutrient though)
Any food with high TMA-oxide content, since the TMA-oxide is broken down to TMA in our gut (e.g. seafood)
Carnitine

2. Avoiding anything that inhibits the FMO3 enzyme
So far, only indoles in cruciferous veg have been proven to inhibit the enzyme. It's possible more foods are to be discovered.
In humans, most carnitine in the diet is derived from lysine and methionine, so anything high in these 2 amino acids will naturally result in the most carnitine. This shows how difficult it is to avoid, given that lysine and methionine are in many foods. 2 common main sources are red meat and in the whey portion of dairy foods. But red meat is the most abundant food by far, as can be seen in the table in this page : Office of Dietary Supplements info on carnitine

For those that feel only trimethylamine causes their odor, perhaps carnitine is worth further investigation to see if this could be a secret source of TMA in your diet. In general, it seems that those on a strict vegetarian or vegan diet may have very little carnitine in their diet, but it must be remembered that lysine and methionine are essential amino acids.

http://en.wikipedia.org/wiki/Carnitine

http://ods.od.nih.gov/factsheets/carnitine.asp