Which lab test did you do for folate? The reason I ask is if the lab doesn't separate folic acid from folate, your high range could be because you have high folic acid levels. This would likely be from eating foods enriched with folic acid. I see you're in Germany and I don't know if they enrich their white flours and other cereals with folic acid like here in N America. Folic acid can block natural folate from reaching folate receptors.
Here's a breakdown of the different folates that can be tested for and what results would mean (from Rich Vank):
5-CH3-THF: This is a measure of the concentration of 5L-methyl
tetrahydrofolate in the blood plasma. The reference range is 8.4 to 72.6 nanomoles per liter.
This form of folate is present in natural foods, and is normally the most abundant form of folate in the blood plasma. It is the form that serves as a reactant for the enzyme methionine synthase, and is thus the important form for the methylation cycle. It is also the only form of folate that normally can enter the brain. Its only known reactions are the methionine synthase reaction and reaction with the oxidant peroxynitrite.
When there is a partial block in methionine synthase, the other forms of folate continue to be converted to 5L-CH3-THF by the so-called “methyl trap” mechanism. Some of the 5L-CH3-THF is broken down by reaction with peroxynitrite, which results from the condition of oxidative stress that is usually concomitant with glutathione depletion.
Many PWCs have a low value of 5L-CH3-THF, consistent with a partial block in the methylation cycle. Most methylation treatment protocols include supplementation with 5L-CH3-THF, which is sold over-the-counter as Metafolin, FolaPro, or MethylMate B (trademarks), as well as the newer Quatrefolic (trademark) and in the prescription “medical foods” supplied by PamLab, including Deplin, CerefolinNAC and Metanx. There are some others on the market that include both racemic forms (5L and 5R) of this folate.
When methylation treatment is used, the level of 5-CH3-THF rises in nearly every PWC. If the concentration of 5-CH3-THF is within the reference range, but either SAM or the ratio of SAM to SAH is below the reference values, it suggests that there is a partial methylation cycle block and that it is caused by inavailability of sufficient bioactive B12, rather than inavailability of sufficient folate. A urine organic acids panel will show elevated methylmalonate if there is a functional deficiency of B12. I have seen this combination frequently, and I think it demonstrates that the functional deficiency of B12 is the immediate root cause of most cases of partial methylation cycle block. Usually glutathione is low in these cases, which is consistent with such a functional deficiency. As the activity of the methylation cycle becomes more normal, the demand for 5-CH3-THF will likely increase, so including it in the treatment protocol, even if not initially low, will likely be beneficial.
10-Formyl-THF: This is a measure of the concentration of 10-formyl
tetrahydrofolate in the blood plasma. The reference range is 1.5 to 8.2 nanomoles per liter.
This form of folate is involved in reactions to form purines, which form part of RNA and DNA as well as ATP. It is usually on the low side in PWCs, likely as a result of the methyl trap mechanism mentioned above. This deficiency is likely the reason for some elevation of mean corpuscular volume (MCV) and mean corpuscular hemoglobin (MCH) often seen in PWCs. This deficit may also impact replacement of cells lining the gut, as well as white blood cells.
Rarely, 10-formyl-THF is found to be much higher than the normal reference range. If this is found, the patient should be examined for cancer, since cancer cells upregulate this form of folate in order to make purines more rapidly to support their rapid cell division.
5-Formyl-THF: This is a measure of the concentration of 5-formyl
tetrahydrofolate (also called folinic acid) in the blood plasma. The reference range is 1.2 to 11.7 nanomoles per liter.
This form is not used directly as a substrate in one-carbon transfer reactions, but it can be converted into other forms of folate, and may serve as a buffer form of folate. Most but not all PWCs have a value on the low side. It is one of the
supplements in some methylation protocols. It can be converted to 5L-CH3-THF in the body by a series of three reactions, one of which requires NADPH, and it may also help to supply other forms of folate to the cells until the methionine synthase reaction comes up to more normal activity.
THF: This is a measure of the concentration of tetrahydrofolate in
the blood plasma. The reference range is 0.6 to 6.8 nanomoles per liter.
This is the fundamental chemically reduced form of folate from which several other reduced folate forms are synthesized, and thus serves as the “hub” of the folate metabolism. THF is also a product of the methionine synthase reaction, and participates in the reaction that converts formiminoglutamate (figlu) into glutamate in the metabolism of histidine. If figlu is found to be elevated in a urine organic acids panel, it usually indicates that THF is low. In PWCs it is lower than the mean normal value of 3.7 nanomoles per liter in most but not all PWCs.
Folic acid: This is a measure of the concentration of folic acid in
the blood plasma. The reference range is 8.9 to 24.6 nanomoles per liter.
Folic acid is a synthetic form of folate, not found in nature. It is added to food grains in the U.S. and some other countries in order to lower the incidence of neural tube birth defects, including spina bifida. It is the oxidized form of folate, and therefore has a long shelf life and is the most common commercial folate supplement. It is normally converted into THF by two sequential reactions catalyzed by dihydrofolate reductase (DHFR), using NADPH as the reductant. However, some people are not able to carry out this reaction well for genetic reasons, and PWCs may be depleted in NADPH, so folic acid is not the best supplemental form of folate for these people.
Low values suggest folic acid deficiency in the current diet. High values, especially in the presence of low values for THF, may be associated with inability to convert folic acid into reduced folate readily, such as because of a genetic polymorphism in the DHFR enzyme. They may also be due to high supplementation of folic acid.
Folinic acid (WB): This is a measure of the concentration of folinic acid in the whole blood. The reference range is 9.0 to 35.5 nanomoles per liter.
See comments on 5-formyl-THF above. Whole blood folinic acid usually tracks with the plasma 5-formyl-THF concentration. They are the same substance.
Folic acid (RBC): This is a measure of the concentration of folic acid in the red blood cells. The reference range is 400 to 1500 nanomoles per liter.
The red blood cells import folic acid when they are initially being formed, but during most of their lifetime, they do not normally import, export, or use it. They simply serve as reservoirs for it, giving it up when they are broken down.
Many PWCs have low values of this parameter. This can be caused by a low folic acid status in the diet over the previous few months, since the population of RBCs at any time has ages ranging from zero to about four months. However, in CFS it can also be caused by oxidative damage to the cell membranes, which allows folic acid to leak out of the cells. Dr. Audhya reports that treatment with omega-3 fatty acids has been found to raise this value over time in one cohort.
Which lab test did you do for B12? Levels in the blood don't tell whether the B12 is getting into your cells and being used. High blood levels can mean the B12 is floating around in your blood unable to be transported into your cells for various reasons. Methylmalonic acid (MMA) testing is probably the most accurate test for B12 deficiency.
@splaszzz