Thomas Bridgeland <[log in to unmask]> wrote:
 >I am not sure if limiting methionine would be a good idea. I recall
 >from my nutrition classes that methionine is one of the limiting amino
 >acids. In fact, farmers deliberately add high methionine foods to
 >animal diets. A low level of methionine is not a good thing.

Thanks for your comment.
Actually my idea was to find food items particularly high in cysteine (not
low in methionine). I'm assured by the elaborations of the link Richard
posted recently (nitrogen metabolism).

I sorted for Cyst/Meth ratio because Meth-->Cyst is the pathway which makes
homocysteine. But there may be food items just low in Methionine with show
up top of the list.

Then you should look after those food items simply high in Cysteine
or *relative* high per protein. I have columns for this, like
  "Ratio CystY/Protein". I can sort after this.

In this criteria again lentils and chestnuts are top of the dogs.
They just have a very high part of cysteine of all protein.
Therfore little need to make more of it (involving homocysteine).

So again: not limiting methionine, just supplying enough of cysteine should
shut down the homocysteine pathway.

 >That said, anyone eating much meat is getting plenty of methionine. All
 >animal products are high in it, as are most beans. Methionine is the
 >amino acid that vegetarians are adding beans to balance for.

I just checked again and found legumes to be not very high in methionine.
Lentils .077 kindney beans .130 --  half that of ordinary wheat.
It must be something else. I know that each one, cereals and legumes are
relative short in one of the amino acids. By accident exactely that amino
acid low in the one is particularly high in the other.
Together, therefore a mix of them results in a very high protein quality
(better even as eggs and meats).

Back to cysteine: of course you are right, anyone eating much meat (or else
proteins) will eat enough cysteine too.
But.
If you ate 1 pound of beef (17% protein and  0,185 cysteine 0,43 met)
you get 5*.185 ~1g of  cysteine and (86g protein).
If you are 1 pound almonds (21% protein and 0,282 cysteine 0,188 met)
you get 5*0.282 = 1.4 g cysteine (and 106 g protein).

40% more cysteine for the same weight (and similar protein).
It would be easier to meet our high cysteine requirements with almond
protein. And it would not involve homocysteine.

regards

Amadeus