Homocysteine is an inflammatory marker that plays an important role in the methylation cycle.
It is an amino acid not used in protein synthesis. Its role is to serve as an intermediate in methionine metabolism. Homocysteine itself is located at a branch-point of metabolic pathways where it is either irreversibly degraded via the transsulphuration pathway to cysteine or it is remethylated back to methionine.
Homocysteine is tested with as part of the Walsh Panel in order that therapy for undermethylation does not result in higher levels of homocysteine. It is a marker of cardiovascular inflammation so treatment with methylation supplementation may increase levels and increase risk of cardiovsacular incident.
In it’s re-methylation pathway, homocysteine requires the presence vitamins B12 and folic acid and or TMG -trimethylglycine to convert back into methionine. But an elevated level alone is not enough reason to treat these supplements. Folic acid, for instance, may improve methylation while lower homocysteine but it also has a remarkable effect of reducing the activity of serotonin and dopamine, which could be harmful to ones mental or emotional well being if functioning at low level of serotonin and dopamine. On the other hand it may not be good to supplement with B12 and TMG without knowing whether or not someone is overmethylated (histamine test) if they are emotionally unstable. This is because increasing methylation will worsen the condition by increasing the levels of serotonin and dopamine, which are already elevated in these persons. With genetic evidence of MTHFR SNP’s and other problems associated with folate deficiency, one has to carefully consider the importance of each symptom and consequence of remedy.
Given the complexity of this issue it is always advisable to consult with a trained practitioner before supplementing to treat homocysteine and methylation imbalances.
Lab reference ranges for homcysteine are often stated as >15uM. A more conservative approach would address the homocysteine levels if elevated to >8uM.