Individuals with an MTHFR mutations have a reduce ability to produce Methylfolate the active form of Folate (Vitamin B9). Folate is crucial to Methylation: what help us repairing our cells and DNA or making new ones (think about pregnancy), metabolizing histamine, balancing neurotransmitters and making Glutathione (our master antioxidant so important to eliminate toxins (viruses and getting rid of their toxins).
How Stress plays a role in this?
Stress speeds up everything, our heart rate, our consumption of vitamins, including the much-needed folate. This is true for everyone whether you have the MTHFR mutation or not. Acute stress can easily be dealt with and does not impact our overall health but chronic stress as it makes our body burns constantly more nutrients does.
Having MTHFR puts us at additional risk of nutritional deficiency making our immune system much more fragile and makes us more susceptible to infections.
It is now considered that limited methylation capacities as experienced by individuals with MTHFR mutations is a potential factor playing a role in chronic viral infections (H. Pilory, EBV, etc.…). Old viruses, dormant infections, can be reactivated by chronic stress and lack of methylation.
Elevation of cortisol when we are stressed affects our immune system and reduce our NK cells (Natural Killers) and increase cells multiplication in response to the infection or stimulated by the virus itself.
Therefore, people get sick when a significant event happens in their life (getting a new job, a divorce, training very hard etc.) I a firm believer that every chronic infection is linked to chronic stress and poor methylation (MTHFR mutation, bad diet and lifestyle or both).