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Illustration by FAIM / © 2024
Thyroid Function
What are the warning signs of thyroid imbalance? Let’s get to that, but first some basics:
Your thyroid gland is a butterfly-shaped gland at the front of your neck that regulates metabolism (how your body uses energy) but also influences:
- Metabolic rate
- Heart rate
- Blood pressure
- Body temperature
- Gut motility
- Mental function
- Mood
- Menstruation
- Fertility
Signs of an overactive thyroid include feeling anxious or irritable, difficulty sleeping, racing heart, shaking hands, clammy skin, sensitivity to heat, unexplained weight loss (or gain), or irregular periods.
Signs of an underactive thyroid include feeling tired all the time, mood swings, brain fog, dry skin, hair loss, brittle nails, constipation, sensitivity to cold, unexplained weight gain, or heavy periods.
The only way to know how your thyroid is functioning is to TEST.
Still, thyroid imbalances are sometimes missed by routine screenings, and even when labs are brought into the normal range, patients can still not feel well.
Watch for my upcoming post all about how functional medicine can help you understand, address, and optimize thyroid function.
Thyroid Tests
Labs to test for thyroid function are important. This article is for anyone who goes to their annual checkups, gets routine lab tests, and has been told their thyroid is normal, but still has unexplained health issues.
You know something’s not right.
This is not to say that thyroid is the cause in your case (only the tests can say that), but it is to say that routine screenings often only test for TSH and miss thyroid problems.
TSH stands for Thyroid Stimulating Hormone, which is the hormone released from the brain to stimulate the thyroid gland to release thyroid hormone (T4). It is only one of several markers of thyroid function.
Other thyroid tests include:
- T4 and free T4
- T3 and free T3 (active hormone)
- Reverse T3 (inactive hormone)
- Antibodies (TPO, Tg, or TRA)
The thyroid gland regulates metabolic rate, gut motility, body temperature, hair, nails, and more.
Naturopathic / Functional Medicine
How do we optimize thyroid function beyond TSH?
Anyone who struggles with thyroid function knows that it’s all too common for their labs to look “fine” and yet still feel tired all the time or have mood swings, brain fog, constipation, hair loss, or other concerns. This is usually because no one is looking at the bigger picture.
From a functional perspective, it is important to also:
- Monitor more than just TSH.
- Optimize nutrition for thyroid hormone synthesis.
- Support conversion of T4 to the more active T3.
- Calm inflammation & oxidative stress.
- Identify & address root causes (metals, toxins, nutrient deficiencies, infections, stress, etc.).
Thyroid-Gut-Liver
Want better thyroid function? Then we also need to optimize the liver and the gut. Here’s why:
Thyroid & Gut
Thyroid hormones influence gut motility (causing constipation when underactive). Gut dysbiosis or inflammation can worsen oxidative stress that damages the thyroid.
Thyroid & Liver
Thyroid hormones influence fat metabolism in the liver (contributing to insulin resistance and fatty liver when underactive). Conversion of T4 to active T3 takes place in the liver, meaning that a compromised liver could compromise thyroid function. Poor thyroid function can impair gut and liver function, and the reverse is also true.
If you struggle with thyroid health and want to take a holistic approach to feeling better, consider contacting a functional medicine practitioner through the website www.ifm.org.
Hormones
Rarely is a thyroid problem JUST a thyroid problem. The thyroid is part of the larger endocrine system, which includes hormones produced in the brain, adrenals, ovaries, and pancreas.
Here are three hormones that influence (and are influenced by) the thyroid:
Insulin – Both overactive and underactive thyroid can disrupt glucose metabolism and contribute to insulin resistance. The reverse is also true, with insulin resistance being associated with conversion of T4 to reverse T3 (inactive thyroid hormone) rather than active T3.
Cortisol – Underactive thyroid contributes to higher cortisol levels (a stress hormone) because of reduced cortisol clearance. Also, high levels of cortisol are associated with reduced T4 production and higher levels of reverse T3 (inactive thyroid hormone).
Estrogen – The hormone cascades connecting the brain to the thyroid and the brain to the ovaries work together. Both overactive and underactive thyroid can disrupt the menstrual cycle and irregular periods or fertility challenges.
It’s because of these connections that it’s so important to take a holistic approach when optimizing thyroid function.
EDCs
If you want to optimize thyroid function, avoid Endocrine-Disrupting Chemicals (EDCs). These are chemicals that mess with our hormonal systems, including the thyroid gland.
Specific chemicals that are known to disrupt the thyroid are:
- BPA (in plastics)
- Phthalates (in personal care products)
- PCBs (in seafood)
- PBDBs (flame retardants in furniture & carpets)
Studies show that some of these chemicals disrupt thyroid hormone production, while others interfere with thyroid hormone transport or receptors. You can see from this list that these chemicals are everywhere in our daily lives.
Still, we can minimize our exposure by choosing foods not packaged in plastics, clean personal care products, and safer seafood.
This is why a holistic approach to thyroid health not only looks at nutrition and how different body systems interact, but also at how to reduce the body burden of chemicals and environmental toxins.
Holistic Health Tips
Five Ways to Support Conversion of T4 to T3
For anyone looking to optimize their thyroid function, this is ESSENTIAL.
Your thyroid gland makes hormone in the form of T4, which is then converted into the more active T3 in other areas, especially the liver. If this conversion is sluggish, you may feel the effects of low thyroid function even if T4 levels are within the normal range.
Here are some ways to support the conversion:
- Liver Support – Since conversion of T4 to T3 happens primarily in the liver, supporting healthy liver function also supports healthy thyroid function.
- Gut Support – The enzyme needed to convert T4 to T3 is also present in the gut wall, so gut health may influence T3 levels.
- Nutrient Optimization – T4 to T3 conversion depends on selenium and zinc, found mainly in meats, nuts, and seeds.
- Stress Management – Anything the body perceives as stress triggers the release of cortisol. Higher levels of cortisol are associated with more conversion of T4 to reverse T3 (inactive form) rather than the active T3.
- Blood Sugar Balance – Similar to the effect of stress, insulin resistance is associated with more conversion of T4 to reverse T3 (inactive form) rather than the active T3.
Foods
Is there an optimal diet for the thyroid?
First, foods that may harm thyroid function are the same ones that otherwise promote inflammation, disrupt blood sugar balance, or create stress in the body:
- Hydrogenated and trans fats
- Sugary or highly refined foods
- Seafood high in environmental toxins (like PCBs)
Depending on the person, sensitivities to gluten or other specific foods may also trigger immune responses and inflammation that damage the thyroid.
On the other hand, foods that support thyroid function either deliver essential nutrients or combat oxidative stress and inflammation:
- Omega-3 essential fatty acids
- Meats, nuts, and seeds high in trace minerals
- Plant foods for antioxidant phytonutrients
Plus, studies have shown that the Mediterranean diet may specifically benefit thyroid function. This is a big topic and needs to be individualized to the person!
Nutrients
There are essential trace minerals for the thyroid. Your thyroid gland regulates your metabolism, mental function, mood, and more, but it can’t do its job without some essential nutrients.
- Iodine – Iodine is a building block for thyroid hormones. Both too much and too little of this mineral can harm the thyroid, so do NOT supplement without professional guidance. Top food sources include seaweed, seafood, and iodized salt.
- Magnesium – Magnesium is needed for the thyroid gland’s utilization of iodine and for the conversion of T4 to T3. Top food sources include nuts, seeds, and green leafy vegetables.
- Selenium – Selenium acts as a cofactor for enzymes that convert T4 to the more active T3. Top food sources include Brazil nuts, organ meats, and seafood.
- Zinc – Low zinc levels have been associated with both underactive and overactive thyroid conditions. Top food sources include pumpkin seeds, oysters, and meat.
Whether or not you have thyroid concerns, eating nutrient-dense foods can help to optimize your thyroid function.
Goitrogens
You may have heard of “goitrogens” or foods that interfere with thyroid function. Specifically, these foods interfere with the uptake of iodine into the thyroid gland and the ability of the thyroid to make thyroid hormones.
But when you see a list of goitrogenic foods, you’ll notice that many of these foods are healthy and nutrient-dense foods, like:
- Broccoli, cauliflower, kale, Brussels sprouts, & collards
- Flax seeds, pine nuts, & peanuts
- Millet, corn, & sweet potatoes
- Tofu, tempeh, edamame, & soy milk
While it’s possible for these foods to cause thyroid problems, most people are able to eat moderate amounts without them affecting the thyroid. Here’s what’s good to know:
- Steaming, boiling, or fermenting these foods reduces the goitrogenic effect
- People with an underlying iodine deficiency are at a higher risk of developing thyroid problems when consuming goitrogens
- The biggest risk comes in when these foods are consumed raw and in concentrated amounts (like juices)
Dietary choices always need to be individualized, which is why it is best to work with a knowledgeable practitioner.
Three Things
To optimize your thyroid health, STOP doing these three things:
- Stop over-exercising
- Stop under-eating
- Stop over-caffeinating
Do you know why? Because all of these things are perceived by your body as stress.
That means they trigger your adrenal glands to produce cortisol, which causes T4 to convert more into reverse T3 (inactive) and less into active T3.
I get it, anybody struggling with thyroid concerns knows that you can be tempted to do all of these things just to try to combat the energy drain or weight gain.
But what if instead, you could calm inflammation and address underlying issues related to thyroid health (like toxins, infections, or nutrient deficiencies) so you could feel good without these temptations? Approaching health in a holistic manner can help.
Surprising Habits
Surprising habits that support the thyroid which are backed by research include:
- Yoga
- Walking
- Vagal Toning
When it comes to thyroid health, it’s tempting to focus on nutrition. But the thyroid is part of the larger endocrine system and can therefore also benefit from activities that regulate the nervous system.
References
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Revised by Joanne Quinn, PhD; content provided by Wellnesswriter.com.