What is Methylation?

Methylation refers to the process of adding a chemical structure known as a methyl group (CH3-) to another molecule or atom. Many processes in the body depend on methylation to function properly, including the removal of heavy metals, regulation of gene expression, protection from cancer, mounting an immune response and protecting the body from cardiovascular disease and inflammation.

S-adenosylmethionine (SAMe) is the body’s main one carbon methyl donor.


There are a number of nutrients that are critical for SAMe synthesis, including adequate sulfur amino acids, vitamin B6, vitamin B12 and folate. Theoretically, if adequate cofactors are available, the Methylation process (shown below) could go on forever with only minimal addition of sulfur to the system. However, in real life, there are many things that can deplete sulfur amino acids from the system; these are detailed in Part 1 of this series.


Figure used with permission from Mary Hinz, MD.

Sources of sulfur

The next logical question is how to replace the sulfur that is depleted from the system. Many people choose to take supplemental SAMe to do this, and this approach can work very well. However, research has shown that about 4500 mg of sulfur amino acids need to be taken every day to supply all our bodily needs. It would cost about $1300 per month to take this amount of SAMe, which is obviously cost prohibitive.

Luckily, this isn’t our only option. Research has shown that the body can utilize any of the four sulfur-bearing compounds circled above as sources of sulfur for the methylation cycle. This means that we have options. The least expensive option is to use L-cysteine; this is what we have chosen to do by using CysReplete. To supply the body 4500 mg of sulfur amino acids daily costs about $60 using CysReplete.  A person could also choose to use methionine (at a monthly cost or glutathione (at a month cost of about $1500) for this same purpose. You can quickly see that CysReplete is clearly the most cost effective method to obtain the sulfur compounds the body needs to function properly.


Part 3 in this series will show several other benefits of using CysReplete in the management of neurotransmitter imbalances.