Interview with QS24: Focus on Hashimoto, Iodine and L-Thyroxine

Thyroid conditions such as Hashimoto's are affecting an increasing number of people and continue to raise many questions. In particular, the role of iodine and the frequent prescription of L-thyroxine are subjects of ongoing debate. We were invited to appear on the Swiss health television channel QS24 to shed some light on these issues. Alongside host Corina Klein, we explored diagnostic pathways, laboratory values and the potential impact of synthetic iodine intake on thyroid function. The conversation covered both medical correlations and practical experience from therapeutic work. The full interview was broadcast on QS24 and is available to watch on their website.

As hormone specialists, we joined QS24 and spoke with Corina Klein about Hashimoto’s disease, iodine management and the widespread use of L-thyroxine. We discussed diagnostic criteria, laboratory parameters and the potential effects of synthetic iodine supplementation. The full interview was broadcast on QS24 and is available to watch on their platform.

A Conversation with Corina Klein and Dr Isabella Wilden

Working with Bioidentical Hormones.

We have supported patients with hormonal concerns for many years. Our approach is rooted in a holistic perspective and an individualised assessment of each person’s hormonal situation.

Host: A warm welcome to our viewers. Today on Health TV, I’m speaking with our bioidentical hormone expert, Dr Isabella Wilden. We’ll be discussing Hashimoto’s and its connection to iodine. Is there truly an iodine deficiency, or are we actually facing an excess? We’ll also examine why L-thyroxine is so frequently prescribed. It’s a complex topic, but our aim today is to provide clarity.

Host: Hello Isabella, it’s wonderful to have you back.

Dr. Isabella Wilden: Thank you for the invitation. I’m very pleased to be here.

Host: I’m delighted as well. You’ve been guiding people in the field of bioidentical hormones for over ten years, taking the time for thorough analysis and viewing each person as a whole.

What concerns me is how many women are prescribed L-thyroxine. Sometimes it feels as if it's handed out without much consideration. A diagnosis is made and medication is prescribed immediately. What is actually happening in the body and within the medical system?

Iodine Supply and the Myth of Iodine Deficiency

Whether a true iodine deficiency still exists today is at the centre of many health debates. Dr Isabella Wilden challenges the commonly accepted assumption.

Dr. Isabella Wilden: I will speak about iodine somewhat differently from conventional medicine. In Germany, there is a working group dedicated to iodine deficiency, and the prevailing message is that it is widespread. This view persists even though we have been consuming iodised table salt for decades.

In my opinion, the topic of iodine has not been thoroughly examined. The iodine added to salt exists in a chemical form. It is often combined with substances such as ferrocyanide and cyanide, as well as something that is sometimes referred to as synthetic iodine. This is marketed as high-quality salt, which I personally find hard to fathom.

Host: So iodine acts as a chemical substitute in salt, yet it is still presented as necessary and beneficial. On what basis is it assumed that we absolutely need iodised salt?

Dr. Isabella Wilden: Primarily on convention. Iodine is difficult to measure reliably in the blood. While tests exist, they are not particularly precise.

Later, urinary iodine excretion became the standard measurement method. However, this test is highly prone to error. Patients must be given detailed instructions beforehand. They must avoid iodised salt, fish, omega-3 supplements and iodine-containing supplements for several days beforehand. Otherwise, the test results are meaningless.

The threshold is set at 100 micrograms per litre. Values below this threshold are classified as deficient, while values above it are normal. However, there is no differentiation between 200 and 5,000 micrograms per litre. Consequently, excess iodine intake is practically undetectable.

Synthetic iodine and rising antibodies

Recent studies and clinical observations suggest that a high intake of synthetic iodine can be problematic.

Dr. Isabella Wilden: There are now numerous studies [2] indicating that, at least in the Western world, we no longer face a general iodine deficiency. When we add chemically produced iodine through supplements or iodised salt, it is not natural iodine. Standard testing methods can only detect small quantities and are unable to reliably identify potential excess.

This chemical form may cause the thyroid to downregulate its iodine receptors. Studies also show that Hashimoto antibodies, particularly TPO antibodies, can increase as a result. Indeed, even individuals who are otherwise healthy may test positive for these antibodies.

Until recently, the upper reference limit for TPO antibodies was 34. A reading below this was considered healthy, while a reading above it led to a diagnosis of Hashimoto's. This often caused significant anxiety. Many patients were referred to nuclear medicine specialists and immediately prescribed L-thyroxine. Often, there was no evaluation to determine whether the finding reflected a temporary reaction or another underlying condition. Consequently, many women end up taking thyroid medication long term.

The effects of L-thyroxine on the body

L-thyroxine contains only one thyroid hormone. It can have a substantial impact on metabolism and energy balance.

Host: I have also noticed that thyroid function can sometimes deteriorate when taking L-thyroxine. Endometriosis often appears at the same time. Patients are not viewed holistically.

When women try to assess their own iodine levels, for example by applying an iodine solution to their skin, they often misinterpret rapid absorption as a sign of deficiency. However, this involves a different form of iodine. Chemical iodine may block the thyroid, while another form is recognised by the body but may not be utilised properly.

Dr. Isabella Wilden: In addition, L-thyroxine is often prescribed alongside iodine. At the same time, many women are advised to take iodine supplements. Yet iodine is already present almost everywhere: in bakeries, supermarkets and many processed foods. It is nearly always synthetic iodine.

If TPO antibodies are elevated, the automatic response should not be to prescribe thyroid medication. Most of the women who come to me have been living with Hashimoto's for years. My role is to provide supportive care, for example by prescribing bioidentical hormones.

Host: One case has had a deep impact on me. A 26-year-old woman had been diagnosed with Hashimoto's disease and endometriosis. She was scheduled for surgery and had fully adjusted to taking L-thyroxine. However, something about it felt off. It later turned out that she had several amalgam fillings. If she had remained within that system without further evaluation, the consequences could have been significant. It is concerning how little coordination exists between medical specialties.

Dr. Isabella Wilden: Once thyroid medication is started prematurely, the path is often not entirely reversible. Many of my clients come to me after years of treatment. The key message is to avoid taking medication immediately without first examining other contributing factors.

L-thyroxine contains only one of the five thyroid hormones. It is T4, an inactive hormone. Our cells cannot use T4 directly - they require T3. Converting T4 into T3 is metabolically demanding.

Common consequences of this process include fatigue, weight gain, hair loss and dry skin. The ovaries and the entire hormonal system may also be affected.

Therapeutic approaches and support

Different strategies may be appropriate for managing Hashimoto's and thyroid therapy depending on the individual situation.

Host: What is your approach when someone comes to you having been diagnosed with Hashimoto’s?

Dr. Isabella Wilden: If someone has been taking thyroid medication for many years, it cannot simply be stopped. In such cases, I may consider switching to combination therapy with T3 and T4, or temporarily using T3 alone, to observe how the body responds.

For pregnant women, my first recommendation is to eliminate synthetic iodine from their diet. This means no iodised salt and no iodine-containing supplements. Otherwise, the iodine load for the child can be very high. I assess the entire hormonal profile and aim to reduce the overall dosage where possible.

Among my preferred supportive measures are cold-pressed black seed oil, selenium and vitamin D, with vitamin D levels ideally being above 60. It functions as a hormone rather than a traditional vitamin.

• It is also important to stop taking vitamins and hormones before having blood tests. B vitamins in particular can significantly distort laboratory results. They should be stopped at least five days beforehand, otherwise deficiencies cannot be accurately identified.

This topic is controversial. I am sharing this information not to create uncertainty, but to highlight that alternative perspectives exist. It may not always be Hashimoto's disease. Synthetic iodine is ubiquitous today, and this should be taken into account.

Host: Thank you for being here, Isabella. Today, we have shed light on Hashimoto's and iodine. I hope our viewers have gained valuable insights. Thank you for watching, and we'll see you next time!