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L-Methylfolate (5-MTHF)

aka Folate or vitamin b9.

Forms/Types

This is the active form.

Quality

As with all supplements - buyer beware. It's quite common for supplements to be contaminated with a variety of impurities, often in the form of heavy metals, and/or contain far more or less of the ingredients stated on the label. There's no simple rule of thumb to avoid this, such as avoiding cheap or imported products; expensive or well-known brands produced in-country may be just as bad. Ideally you should take some time to find products (if you can) that;

  • have been laboratory tested on behalf of the manufacturer by a reputable body or company that operates in your country or region (here's an example of a Peak Supps creatine supplement available on Amazon in the UK which has been tested by Eurofins: Creatine Monohydrate Powder 1Kg | Pure Micronised | Packaging May Vary - see pictures 3 & 4)
  • in the UK & EU, are manufactured in facilities that meet the minimum standards of good manufacturing practice (GMP) in their production processes (for medicines).12 Facilities are inspected for compliance and manufacturers' product(s) must:
    • be of consistent high quality
    • be appropriate to their intended use
    • meet the requirements of the marketing authorisation (MA) or product specification

Be wary of any manufacturers or brands making claims around these valid but irrelevant standards;

  • HACCP: this standard relates to food safety which indicates that the seller is claiming their supplement is a food; whilst meeting this standard is worthwhile, GMP (detailed above) would be a more appropriate standard
  • ISO22000: same as HACPP
  • ISO9001: this standard is focussed on quality control management systems in the context of managing a business or organisation, not directly on the the quality of the products that business produces (although it may have a beneficial impact)

Dosage - How Much?

1-2g.

Deficiency - Too Little

Toxicity - Too Much

Side Effects

When to Avoid Use - Interactions/Contraindications

Genetic Factors

The enzyme that converts folate into 5-MTHF is called methylenetetetrahydrofolate reductase (MTHFR). This enzyme is coded by the MTHFR gene. Two common mutations in this gene (C677T/rs1801133 and A1298C/rs1801131) can reduce this enzymes activity and slow conversion of folate. This may impair the process of methylation, which can lead to chronic inflammation, DNA damage and elevated homocysteine levels.

Random Facts

References