How Sugar Wrecks Your Thyroid and Gut (and What to Do About It)

Welcome to Healthy Gut Healthy Thyroid!

This is your weekly roundup of the BEST actionable steps for those people with thyroid and autoimmune thyroid conditions who want to restore their health…by healing their gut. Whether you have hyperthyroidism or Hashimoto’s you will benefit from the content in this newsletter.

In today's issue:

• Main Topic: How Sugar Wrecks Your Thyroid and Gut (and What to Do About It)

• Podcast Review: The Gut-Autoimmune Thyroid Connection with Dr. Heather Finley

• Ask Dr. Eric: Are any hair growth supplements safe for hyperthyroidism?

How Sugar Wrecks Your Thyroid and Gut (and What to Do About It)

There’s no denying that many of us—including myself—have a sweet tooth. In fact, I find this to be the case with many of my patients as well. While natural sources of sugar such as fruit and raw honey can be part of a healthy diet when consumed in moderation, refined sugars and processed foods are far more problematic—and far more common in modern diets.

Growing up, my breakfast often consisted of sugar-laden cereals, similar to the image above. Today, there are seemingly healthier versions on grocery store shelves—organic, gluten-free, and labeled as “natural.” But while these may sound better, many are still highly processed and excessively high in sugar.

The concern, of course, goes well beyond breakfast cereals. Many people are consuming refined sugar all day long—snacking on sugary treats, drinking sweetened beverages, and finishing meals with dessert. While occasional indulgences are fine for most, sugar should be minimized—especially during periods of healing and recovery.

Let’s explore how sugar impacts both thyroid function and gut health, and what you can do to break the cycle.

How Sugar Can Negatively Affect Your Gut and Thyroid

✅ It Disrupts Blood Sugar Balance. Sugar intake causes spikes and crashes in blood glucose, leading to insulin resistance over time. This has a direct impact on thyroid health.

Thyroid hormones significantly influence glucose metabolism:

In hyperthyroidism, glucose intolerance is mainly due to hepatic (liver) insulin resistance.

In hypothyroidism, peripheral insulin resistance in muscle and adipose tissue is more common.

Insulin resistance has been associated with the development of thyroid nodules and can worsen autoimmune thyroid conditions.

Learn more in Newsletter #17, where I discuss this connection in detail.

✅ It Promotes Gut Dysbiosis. Refined sugar fuels the overgrowth of opportunistic organisms like yeast (Candida albicans) and harmful bacteria, disturbing the gut’s natural microbial balance. This state of dysbiosis can lead to leaky gut, a known contributor to autoimmune conditions such as Graves’ disease and Hashimoto’s thyroiditis.

Common signs of yeast overgrowth include:

• Intense sugar cravings

• Gas and bloating

• Brain fog

• A white coating on the tongue

Functional testing options include the organic acids test (OAT), which is particularly helpful for identifying Candida overgrowth. You can read more in Newsletter #4.

✅ It Stresses the Adrenal Glands. Frequent blood sugar spikes and drops trigger the release of stress hormones such as cortisol and adrenaline. Over time, this can lead to adrenal dysregulation and flatten the natural cortisol rhythm, impairing energy, sleep, immune function, and thyroid hormone conversion. A stressed adrenal system can also compromise your body’s resilience to inflammation and infection.

✅ It Drives Inflammation. High sugar intake leads to systemic inflammation. This is not only a major factor in insulin resistance, but also exacerbates autoimmune activity, contributing to autoimmune conditions such as Graves’ disease and Hashimoto’s. Chronic inflammation also hinders the body’s healing capacity and disrupts normal gut function.

Breaking the Sugar–Thyroid–Gut Cycle

To interrupt this destructive cycle, consider the following strategies:

🥦 Focus on an Anti-Inflammatory, Nutrient-Dense Diet. Adopt a whole foods-based approach—such as an AIP or Paleo-style diet—while minimizing or eliminating refined sugars and processed carbs. Even natural sugars like fruit and honey should be consumed in moderation, especially during active healing phases.

🧪 Consider Testing for Imbalances. Functional testing can help uncover root causes. You may want to test for:

• Blood sugar markers: Fasting glucose, insulin, HbA1c

• Adrenal stress: Cortisol levels (saliva or dried urine testing)

• Gut health: Organic acids test (OAT) or comprehensive stool testing

These tests can reveal hidden infections, yeast overgrowth, or blood sugar irregularities that are hindering your progress.

💊 Use Targeted Supplementation. While diet is foundational, certain supplements can support blood sugar balance and gut repair:

For Blood Sugar Support

• Chromium

• Magnesium

• Alpha-lipoic acid

• Berberine

• Gymnema sylvestre

For Candida/Yeast Overgrowth

• Caprylic acid

• Grapefruit seed extract

• Oregano oil

• Berberine

• Undecylenic acid

• Saccharomyces boulardii (beneficial yeast)

Keep in mind that you don’t need to take all of these supplements when dealing with blood sugar imbalances and/or a Candida overgrowth. It’s also a good idea to work with a competent natural healthcare practitioner for specific guidance…especially when using antimicrobial or antifungal agents.

Conclusion

Sugar may taste sweet, but its impact on your thyroid and gut is anything but. From driving inflammation and gut dysbiosis to disrupting blood sugar and adrenal health, refined sugar can silently sabotage your healing journey. If you're dealing with a thyroid or autoimmune condition, reducing your sugar intake is one of the most powerful changes you can make.

The good news? Your body has an incredible ability to heal when you remove inflammatory triggers and provide the right support. Start with your plate, support your adrenals and gut, and consider targeted testing if progress stalls. Your thyroid—and your gut—will thank you.

Save My Thyroid Podcast Review

I have a podcast called "Save My Thyroid", where I discuss how people with hyperthyroidism and Hashimoto's can save their thyroid and regain their health. And during each edition of this newsletter I'll briefly discuss a recent podcast episode.

In a recent podcast episode I chatted with Dr. Heather Finley about the Gut-Autoimmune Thyroid Connection. Dr. Heather explains why low stomach acid, sluggish bile flow, and post-food poisoning symptoms are often red flags in thyroid cases. She shares how conventional approaches miss the deeper causes behind SIBO, constipation, and nutrient deficiencies and how gut issues can slow thyroid hormone conversion. We also touch on practical tools like stool testing, mineral analysis, and even burp tests that offer insight when standard labs fall short. Her approach is rooted in rebuilding function, not restriction.

Click Here to listen to the episode.

Ask Dr. Eric

During every issue I'll answer a question or two that I think can benefit most people with a thyroid or autoimmune thyroid condition. If you'd like for me to consider your question for a future edition of this newsletter email your question to [email protected].

QUESTION: ARE ANY HAIR GROWTH SUPPLEMENTS SAFE FOR HYPERTHYROIDISM?

“Any recommendations for hair growth supplements safe for hyperthyroidism?”

This question recently came up in my Graves’ Disease and Hashimoto’s Natural Solutions Support Group:

While the question focused on hyperthyroidism, it’s important to note that hair loss can occur in both hyperthyroid and hypothyroid conditions. Regardless of the thyroid diagnosis, the underlying approach should be the same: address the root cause first.

Before You Focus on Hair Growth—Stop the Hair Loss

When someone is struggling with hair loss, it's tempting to jump straight into growth strategies. But the first priority should always be to stop the loss. Here are three key areas to address:

Balance Thyroid Hormones. Both elevated and suppressed thyroid hormone levels can disrupt the hair growth cycle, causing increased shedding or thinning. Ensuring that your thyroid hormones—TSH, free T4, and free T3—are within optimal ranges is critical for stabilizing hair loss.

Correct Nutrient Deficiencies. Several nutrients play essential roles in hair follicle health, including:

• Biotin

• Zinc

• Selenium

• Iron

While food should always be your primary source of nutrients, supplementation may be necessary—especially if gut issues are impairing absorption. And of course for optimal nutrient digestion and absorption it’s important to mention that healing the gut is essential.

Address Sex Hormone Imbalances. Hormonal imbalances, particularly elevated androgens (like DHT), can lead to hair thinning or loss. Healthy adrenal function is essential for balanced sex hormone production, especially in women.

Can Hair Growth Supplements Help?

There’s no single supplement that works for everyone, and when dealing with a thyroid condition—especially hyperthyroidism—you must be cautious with ingredients that can overstimulate the body or interfere with thyroid function.

Some hair growth supplements contain:

➡️High doses of biotin, which may interfere with lab testing results if not discontinued before a thyroid panel.

➡️Iodine in the form of kelp that may impact thyroid hormone levels, particularly in those with hyperthyroidism, although iodine can sometimes be problematic in those with Hashimoto's as well.

When hair loss supplements are effective, it's usually because the supplement helps to correct a nutrient deficiency. If you're lacking in a specific vitamin or mineral that supports follicle health, correcting this can result in improvement. However, if the root cause is hormonal or gut-related, supplementation alone is unlikely to be enough.

Additional Thyroid-Related Resources

Click Here for the Gut-Autoimmune Thyroid Condition (episode 210)

Click Here to access hundreds of thyroid-related articles and blog posts

Click Here to join the Graves’ disease and Hashimoto’s community

Click Here to purchase one of Dr. Eric’s thyroid-related books

Click Here to work with Dr. Eric and his team

That’s a wrap