Dr. David Clark, DC - Raleigh-Durham-Chapel Hill Thyroid expert, explains how Serotonin can cause Low Thyroid Symptoms.
Hidden Cause #16 why you STILL have low thyroid symptoms even though you may be taking medication and even though your lab tests look normal is...
A peripheral deficiency in the neurotransmitter Serotonin.
When I say 'peripheral', I’m trying to contrast that to "central," meaning inside your nervous system, and peripheral, meaning in the nervous system in the rest of your body.
You have a ton of serotonin outside of your brain. Your GI tract has a huge amount of serotonin.
In fact, we like to call the GI tract “the second brain” because it really has more neurotransmitters than your brain.
What would a serotonin deficiency look like?
- Intestinal Pain
Essentially, any type of GI symptom could be related to peripheral serotonin deficiency. I realize that’s not super-specific but it's the truth.
As for Central Nervous System symptoms of serotonin deficiency....
Classically, the big symptom is "depression." But what does "depression" look like?
....losing interest in things that were previously pleasurable
...being sad or down for no reason.
...overwhelmed with ideas, can't manage them
....feelings of inner range and anger
....feelings of unprovoked anger
Those are really what we mean by depression.
If you’re having a few of the above symptoms plus LOW THYROID SYMPTOMS like the following, then Serotonin needs to be on the radar.
- Need to sleep excessively just to function
- Hair loss & hair thinning
- Dry Skin
- Brain Fog
- Easily Weight Gain
How does Serotonin affect thyroid hormones?
Research seems to show that Serotonin affects the rate of conversion of T4 into T3.
And if you remember, T4 needs to be converted into T3 (the active form). 97% of what your thyroid gland makes is T4---so to get T3, you’ve got to "convert" T4 into T3.
Conversion is influenced by how much serotonin activity is going on in the periphery of your body.
But as I mentioned earlier, we just don’t see a lot of clear signs of peripheral serotonin deficiency other than those that are related to the gastrointestinal system. So. we have to look more at someone that has central signs of serotonin deficiency (listed above).
What could cause a Central Serotonin Deficiency?
Since Serotonin is made from the amino acid, L-Tryptophan, you could get into trouble if you weren't getting enough L-Tryptophan, or absorbing it...
...however, that's usually NOT the issue.
More often the real problem is LOW Serotonin Activity--in other words, you might be able to make it just fine, but you are NOT making it regularly or consistently...or...your Serotonin RECEPTORS are not responding normally to Serotonin.
Blood sugar regulation and Iron levels are the two critical factors that create Low Serotonin Activity.
If you have low Serotonin symptoms, that doesn’t necessarily mean you need to take L-tryptophan or that you need to take SSRI.
It DOES mean that the doctor you’re working with has got to put on the detective hat and figure out what is YOUR problem with Serotonin?
...Making it (synthesis)
...Using it (receptors)
This takes some digging.
Im the big picture of Thyroid this hidden cause is pretty darn hidden because it’s #16 on the list. Over the last 12 years I haven't seen that many low thyroid patients with this Serotonin problem--especially compared to the number of women with Hashimoto's--but they still show up.
I'll see a woman who’s been taking thyroid medication because she’s got low thyroid symptoms AND she’s got these serotonin symptoms.
Now, you can guess what happens when she walks into most doctors’ offices.
She looks depressed. Sounds depressed. So, she gets labeled with "depression." And is prescribed an anti-depressant--which will not change her thyroid symptoms in the long run.
This is problematic for 2 reasons:
1. If you felt bad for months or years, you might be depressed BECAUSE of that--not the other way around. anyway.
2. A patient can have more than one thing wrong. This is something that’s very hard to get doctors to understand---doctors of all kinds--that there’s no rule that says a patient can have only one thing.
You'll have to look far and wide to find a Doctor that would connect low thyroid symptoms AND low serotonin symptoms to a problem with peripheral Serotonin deficiency.
But the big point is, look, if you’ve got these serotonin symptoms and you feel sad and depressed when there’s no reason for it and you’ve got these low thyroid symptoms, you might need to investigate whether serotonin is an issue for you or not.
So you’ve got to find someone that would know what to look for and how to help you. And how to help you is not immediately running out to GNC and buying L-tryptophan. That’s not necessarily what you need to do.
It’s more complicated than that, and your doctor that you see should know that.
© 2014 David Clark. All Rights Reserved.
Dr. David Clark, DC
Functional Neurologist (FACFN)
Diplomate College of Clinical Nutrition
Board Certified Chiropractic Neurologist
Vestibular Rehab Specialist (ACNB)
1515 W. NC Hwy 54 Ste 210
Durham, NC 27707
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