Newport is god at this;

All Se needs to be converted to Selenomethionine by the body, this requires a working methylation cycle which requires enzymes. These enzymes are usually killed by mercury and/or lead so taking elemental only may throw some people into a methylation cycle problem and the end result of that may be a Homocysteine problem.

more from:
http://aor.ca/int/related_research/homocysteine+.php



Homocysteine is a toxic amino acid and high levels which has been implicated in increasing the risk of cardiovascular disease. Methylation is a metabolic process in the body that involves adding methyl groups and converts homocysteine to useful methionine and SAMe that the body uses. TMG is an excellent source of methyl group whole folic acid, vitamins B6 and B12 act as synergistic co factors are involved in the proper functioning of methylation enzymes.
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