← Learning essentials

Learning essentials · FROM DR. PURSER’S TEACHING

Homocysteine and methylation

Follow Dr. Purser’s teaching on folate, B12, sulfur pathways and antioxidant support around homocysteine.

Based on teaching by Dan Purser, MD. How we prepare these guides

Updated Sep 23, 2026 · Educational reference

THE TEACHING CONNECTION

Follow the branches around homocysteine

Follow the branches around homocysteine

Homocysteine sits at a junction in the pathway. Dr. Purser’s teaching follows homocysteine in two directions: remethylation toward methionine and transsulfuration toward cysteine-related chemistry. Folate/B12 and MTR/MTRR belong in the first discussion; CBS/CTH and glutathione-building materials belong in the second. MTHFR is an important piece, but not the entire map.

Putting the pieces together

His model also brings antioxidant workload and inflammatory signaling into the conversation. Those teaching connections should be distinguished from what a single blood measurement proves. Review current nutrient status, clinical context and changes over time; do not assume that a common SNP means homocysteine cannot change. Lowering a marker is also not the same as demonstrating prevention of every associated disease.

Where the VARS Triad and MTHFR Daily fit

If you are exploring homocysteine or cytokines, Dr. Purser may discuss MTHFR Daily and the VARS Triad: VARS Glutathione, VARS SOD, and VARS Catalase. He gives glutathione a central place in his approach to antioxidant support.

A gene result alone cannot tell you that you need these products or that they will treat a condition. Review your current results, medicines, goals, and tolerance with your clinician before choosing a product or dose.

How immune signals may connect

In Dr. Purser’s model, homocysteine may relate to how cells respond to inflammation. He discusses genes, nutrients, antioxidant status, and the immune signals IL-8 and MCP-1. NF-κB is a switch involved in controlling inflammatory genes.

This pathway helps explain why he looks at more than a homocysteine number. It does not provide a test that can measure your personal 'cytokine sensitivity.'

What IL-8 and MCP-1 do

IL-8 (CXCL8) and MCP-1 (CCL2) are chemokines: messages that help call immune cells to an area. You may see either name on a report.

A lab experiment found that human blood-vessel cells exposed to homocysteine released more of these signals. A change in cells in a lab does not show that a supplement will prevent heart or kidney disease in a person.

More genes than MTHFR

Genes involved in folate use, B12 transport, methylation, and sulfur processing include AHCY, BHMT, FOLH1, MTR, MTRR, SHMT1, TCN2, MTHFD1, MTHFD1L, SLC19A1, CBS, and CTH. Each plays a different role.

A gene name alone does not tell you whether a variant affects your health. Your exact result and its clinical classification matter. Common variants are different from rare inherited metabolic disorders.

Nutrient context: read high and low results carefully

Protein intake and nutrients such as folate, B12, B6, riboflavin, and choline can affect different parts of this pathway. That is why your food history and other tests matter along with a homocysteine number.

A low result does not prove a hidden deficiency. In fact, folate, B12, and B6 deficiencies more commonly raise homocysteine. Ask your clinician to review a change in the number with your overall health picture.

A question to bring to your visit

What do repeated measurements and current folate/B12 findings show, and which part of the pathway is the plan intended to address?

Reading your own results

Bring your original report, current results, health history, and medicines to your visit. This information can help you ask questions, but it cannot diagnose a condition or choose a supplement dose for you.