Wednesday, December 9, 2015
Wisdom Wednesday: Homocysteine
Homocysteine is an amino acid, one of the building blocks for protein. However, homocysteine is not found in the diet. Rather it is manufactured in the body from another amino acid methionine.
Methionine is one of nine essential amino acids that cannot be synthesized in the body and must be in the diet. Methionine is found in most proteins – red meat, turkey, chicken, fish, soy, many cheeses, and yogurt.
When homocysteine is created it is an intermediate metabolite. Vitamin B6 then converts it to cysteine or vitamin B12 and folic acid convert it back to methionine. However, deficiencies of these vitamins or other co-factors can allow homocysteine to accumulate in the blood stream.
In normal metabolism, when damage occurs to an artery wall, a little C-reactive protein (CRP) is created. This stimulates the homocysteine to combine with LDL (low density lipoprotein) and creates a patch over the damaged area of the artery. If, over time, the plaque begins to come loose, the body sends calcium into the plaque to secure it to the artery wall.
In abnormal metabolism (pathology), any of these factors that elevate can allow this repair process to run wild creating atherosclerosis and heart disease. Unfortunately, the first factor discovered in this process was LDL cholesterol. So it was labeled as “bad” and statin drugs were developed to lower the LDL and total cholesterol.
The statin drugs actually do work (a little bit) but they do so because they lower the CRP, not because they lower the LDL cholesterol. In fact, the data never supported the claim that high cholesterol is associated with coronary artery disease. Over half of patients suffering their first heart attack have normal or even low cholesterol.
Despite the development of blood tests for homocysteine and CRP, vital factors in the pathogenesis of heart disease, these tests are not routinely run on patients. Most physicians that prescribe statin drugs do so based solely on the total cholesterol and LDL levels.
High speed CT (computerized tomography) scans of the heart are now used more frequently to detect the presence of calcium indicating “vulnerable plaque”. But physicians are warning patients that calcium can cause heart disease. The calcium actually secures the plaque and is not, in itself, a risk factor but rather a measure of relative risk.
When homocysteine is converted to cysteine by vitamin B6 it can be further broken down to yield free sulfur. The sulfur is then used to make chondroitin sulfate to repair connective tissue (muscle, joint, bone, ligament, tendon, and cartilage), control Candida in the bowel, and facilitate five of the ten pathways of Phase 2 liver detoxification.
For many years, laboratories were not allowed to associate homocysteine levels with heart disease. They could only point out the potential for folic acid, vitamin B6 or B12 deficiency. Suspected vitamin deficiency is still the rationale for running this vital test.
Bottom Line – When you have your cholesterol levels checked, insist on having your physician add a homocysteine and CRP as a minimum. If you have a family history of heart disease add an L(p)a to the list. No patient should be taking statin drugs without careful monitoring of all these levels.