The Relationship Between Serotonin Levels and Mold Exposure

by Dr. Susan Tanner, MD

The question of how serotonin levels may be impacted by mold exposure has been posed to me recently. More specifically, I was asked if mold and mycotoxin exposure could cause lowered levels of the mood-boosting brain chemical, serotonin. Quite honestly, I had to ponder this as my immediate reaction was that I didn’t see a direct connection. But, after thinking about this more, I would have to answer, “Yes, serotonin can be dysregulated following or during toxic mold exposure.”

How did I come to that conclusion? While mold exposure does not automatically result in low or high serotonin levels, when we think about the organs that are impacted by toxic mold, we might then find some of the underlying reasons for the dysregulation of serotonin. For this article, I will explain my thought process to allow you to make your own conclusions.

Serotonin and Mold

Serotonin is best known as the “feel-good” neurotransmitter in the brain.  Made up of the amino acid tryptophan, vitamin B6, and magnesium, serotonin is formed primarily in the gut lining.  It is regulated in and out of brain cells and insufficient levels of serotonin can result in depression, anxiety, PMS symptoms, and gastrointestinal complaints, most notably irritable bowel syndrome.

Gastrointestinal Impact

Overgrowth of mold and candida in the gut can impair the absorption of micronutrients. When micronutrients are not readily available for use by the body, the body does not have access to the aforementioned ingredients (tryptophan, B6, and magnesium) required to produce serotonin.  Over time, deficiencies may become even more profound if the condition continues.  It is also possible for these pathogenic overgrowths in the body to cause the serotonin that is produced to be more inflammatory in nature, thus aggravating the very symptoms (anxiety, depression, etc.) that it is supposed to be mitigating.

Adrenal Stress

Toxicity in and of itself puts an enormous amount of stress on the body. In an effort to buffer this, the adrenal glands react by secreting several different hormones namely adrenaline and the steroids aldosterone and cortisol.  The long-term secretion of these then can ramp up anxiety, cause an elevation in blood sugar, and eventually lead to fatigue and exhaustion.  The adrenal hormones have an indirect regulatory impact on the production and utilization of serotonin through intermediary compounds, the end result being that serotonin production is hindered, sometimes to a great degree. Another issue is that Vitamin B6, one of the ingredients of serotonin, is very important to adrenal function; therefore, when these glands are stressed, they gobble up B6 anywhere they can.

Melatonin Production

Melatonin is decreased with mycotoxin exposure. Additionally, sufficient levels of melatonin support good serotonin metabolism. Thus, melatonin not only helps with sleep but also may help with feelings of overall wellbeing, largely due to its impact on serotonin.

Liver Detoxification

Being overburdened by mycotoxins and mold causes the liver to have a hard time with its phases of breaking down not only toxins but hormones and their byproducts.  This, in turn, may cause improper signaling for not only serotonin production but also its uptake by the brain cells.

The big point here is that everything is connected in our organ and hormonal systems.  There are many other ways in which serotonin can be affected by mold and mycotoxins but I feel the above gives a good example of the how’s and why’s of this situation, even though it is absolutely not all-inclusive!

Addressing Serotonin Post Mold Exposure

If you have had mold exposure and feel anxious, depressed, exhausted, and/or unfocused, then it may be a good idea to specifically look at your neurotransmitters, specifically serotonin, to see if support would be in order.  That said, if you are still living in moldy surroundings with contaminated belongings, then your environment must be addressed first.  Anything else will not be effective if you continue to breathe contaminated air.  If leaving is not an immediate possibility, use interventions like mold plates and a fogger to monitor and address your home environment as best you can!!!

Testing:  Testing of neurotransmitters, such as serotonin, can be done but the method and interpretation are extremely important.  Because there is quite a bit of fluctuation in serotonin levels throughout the day, even minute to minute, capturing a single level with blood may not enlighten us very much.  If doing neurotransmitters, then looking at both blood and urinary excretion together helps, because, in this type of testing, not only are the neurotransmitter levels examined but also their breakdown and build-up products and byproducts to paint a clearer picture of the situation and to offer a path to remedy.  While I run these neurotransmitter tests in certain very complex cases, I often find that an Organic Acids test helps determine not only if serotonin is low (by detecting the breakdown metabolite in the urine) but also a host of other helpful information, therefore giving more “bang for the buck”, in my opinion.

Treatment:  As mentioned, reduction of any exposures and detoxification of mycotoxins is first and foremost. Repair of the gut lining follows by eradication of yeast and mold and reduction of inflammation therein.  The use of probiotics and gut repair is hugely significant and goes a long way toward correcting the serotonin imbalance.

Adding the missing ingredients: This is the final step. Per the organic acids test, we often find deficient levels of Vitamin B6 and magnesium, along with the low metabolites to serotonin, indicating a need for tryptophane. While the amino acid L-Tryptophane can be used, we have found that 5 HTP (5 hydroxytryptophans) seems to be more readily available and well assimilated into the system.  A caveat here is if you are already on a medication that is classified as a serotonin reuptake inhibitor, (brand names include Prozac, Paxil, Lexapro, Zoloft) then you must be careful about the addition of more tryptophane so as not to induce what is called a “serotonin storm”, resulting in flushing, blood pressure elevations and diarrhea.  While very rare, it can happen and I always recommend that you consult your physician before the addition of any supplements with the potential to interact with your medications.

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