Improving thyroid health starts with improving how our body converts thyroid hormone through the inactive to active forms.  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 routine labs are within the normal range. If you want to learn more about thyroid lab values, look at last week’s blog post on Understanding Thyroid Labs.

Some ways to support T4 to T3 conversion include:

• Liver Support

• Gut Support

• Nutrient Optimization

• Stress Management

• Blood Sugar Balance

This is why (especially when it comes to the thyroid), we always take a whole-body approach. 

Let’s break it down into each section to understand a little more deeply about how we can improve thyroid health. 

Liver Health

The liver is a primary site for the conversion of T4 to T3. Thyroid hormones influence fat metabolism in the liver (contributing to insulin resistance and fatty liver when underactive). And also 🔁conversion of T4 to active T3 takes place in the liver, meaning that a compromised liver could compromise thyroid function. 

How to support your liver for thyroid function:

• Detoxification: Support liver detoxification pathways by consuming cruciferous vegetables (like broccoli, kale, and Brussels sprouts), which enhance the liver's ability to process toxins.

• Hydration: Proper hydration supports liver function, so aim to drink plenty of water throughout the day.

• Avoiding Toxins: Reduce your exposure to environmental toxins and pollutants, as these can burden the liver. This includes limiting alcohol consumption and avoiding processed foods. If you want a deeper dive on the toxins that junk up the thyroid, look back on my environmental toxin blog.

Gut Health

A healthy gut is crucial for overall thyroid health and effective T4 to T3 conversion. The gut microbiome influences the immune system and inflammation levels, both of which impact thyroid function. Thyroid hormones also influence gut motility (causing constipation when underactive).  And also 🔁 gut dysbiosis or inflammation can worsen oxidative stress that damages the thyroid. 

The gut is also responsible for nutrient absorption, which is critical for thyroid function. An unhealthy gut can lead to deficiencies in these nutrients, impairing thyroid function, leading to symptoms of hypothyroidism even if the thyroid gland itself is functioning normally.

Need another reason to love probiotics? 

A recent review found that probiotics support liver health—even in individuals with advanced liver disease (cirrhosis). The analysis of 30 studies concluded that probiotics (compared to controls) not only improved the gut microflora but also improved liver function and enhanced quality of life in people with cirrhosis. 

Although this review looked at participants with cirrhosis, other studies have found probiotics to offer benefits for liver health in people without such advanced disease. This is an excellent reminder that your microbiome has far-reaching effects on the body that begin in the gut and the liver!

How to support your gut for thyroid function:

• Probiotics and Prebiotics: Incorporate foods rich in probiotics (like yogurt, kefir, and fermented vegetables) and prebiotics (such as garlic, onions, and bananas) to support a healthy gut microbiome.

• Fiber-Rich Diet: A diet high in fiber supports digestion and helps maintain a healthy gut lining. Include plenty of fruits, vegetables, and whole grains.

• Avoid Gut Irritants: Minimize intake of foods that can irritate the gut, such as processed foods, sugar, and excessive caffeine or alcohol.

Key Nutrients for Thyroid Health

Certain nutrients are essential for the conversion of T4 to T3. Trace minerals are essential for thyroid function—which relates to your metabolism, mood, and more (see below for more on what the thyroid does!) Here are 5 nutrients the thyroid needs:

🔸Iodine (in seaweed, seafood, and iodized salt) - The thyroid gland uses iodine to produce thyroid hormones.

🔸Selenium (in Brazil nuts, organ meats, and seafood)  - Selenium is a cofactor for the enzymes that convert T4 to T3. 

🔸Zinc (in pumpkin seeds, oysters, and meat) - Another important nutrient for thyroid hormone production and conversion. 

🔸Iron (in red meat, lentils, and spinach) -  Iron deficiency can impair thyroid function.

🔸Vitamin D (in fatty fish and sunshine) -  Vitamin D plays an important role in immune function and stabilization for the thyroid

Whether or not you have thyroid concerns, eating nutrient-dense foods can help to optimize your thyroid function. 

Thyroid & the Stress Effect

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. Chronic stress can negatively impact thyroid function by increasing cortisol levels, which can inhibit the conversion of T4 to T3.

Anything your body perceives as a stress triggers the release of cortisol, which impairs thyroid function. 

More specifically, cortisol causes more T4 to convert to reverse T3 (an inactive form) instead of to active T3. 

Stressful triggers a lot of people don’t think about include:

• Over-exercising

• Under-eating

• Over-caffeinating

Fortunately, there are some simple habits that we can do to lower the stress effect on the thyroid:

Yoga, walking, and vagal toning exercises are some examples of surprising (and research backed 📚) habits that support the thyroid!

Adequate Sleep: Ensure you get enough restorative sleep, as sleep deprivation can contribute to stress and hormonal imbalances.

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 with functional medicine, we can move past these quick fixes and create long-term solutions. 

Blood Sugar Balance and Nutrition

I often get questions about the perfect diet for thyroid health.

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 must be individualized to the person!

Take a look at the whole picture

When it comes to not just managing thyroid health, but elevating thyroid health, we need to look at the whole picture. 

If you are looking for an approach that looks at the whole-person: nutrients, digestion, immune, nervous system, hormones, inflammation, detox… then fill out our short online form and our clinic liaison will follow up with you about how we can help your thyroid health.