The Functional Approach to Thyroid Disease

Current Medical Approaches to Thyroid Disease 

The most common cause of thyroid disease is autoimmunity, and the burden of this is mainly borne by women (occurring in up to 15% of the female population compared with up to just 5% of men)¹. With onset usually in 30 -50 year olds, and often triggering with changes in hormones (pregnancy and menopause), common presentations include fatigue, weight gain, feeling cold, low mood, hair loss, joint pains and ‘brain fog’.  

However, unless tested for, thyroid autoimmunity is easily missed and put down to signs of stress or Perimenopause. 

The usual approach to thyroid disease is to try to delay intervention for as long as possible, then treat with Thyroid replacement hormone when either the symptoms (or TSH) are deemed to be sufficiently abnormal. Following treatment commencement, the goal is to normalise the Thyroid Stimulating Hormone levels (or TSH), often regardless of how the patient feels. 

Fortunately, the vast majority of hypothyroid patients will respond well to the standard Levothyroxine / T4 hormone replacement therapy, and this does a great job of helping to restore normal Thyroid hormone levels and metabolic functioning. 

However, this medication will not address the ‘root causes’ of the low thyroid output (often nutritional deficiency or autoimmunity), damage to tissues from thyroid antibodies will usually continue (often with associated hair loss and joint pains), and sadly, this medication simply doesn’t seem to help everyone. 

In addition, despite reassurance from medical professionals that other solutions are unnecessary, up to 15% of patients given Levothyroxine report persistent symptoms despite a normal TSH^2,3. This is well documented and can often be explained by downstream problems with the processing or activation of the inactive T4 hormone to the active T3 version. 

Unfortunately, we suspect that driven by a combination of the astronomical price hike in T3 (between January 2009 to July 2017, the cost of T3 to the NHS rose from £15 to £258 per month for a typical prescription dose),⁴ and concerns about possible increased health issues seen in patients on T4/T3 combination therapy compared to T4 alone,^5,6 the prescription of T3 is being deliberately phased out of UK NHS prescribing.⁷ 

This means that a small but significant proportion of hypothyroid patients are being denied beneficial and potentially life-altering treatment. In addition, many NHS endocrinologists are becoming indifferent or even antagonistic towards trials of T3 – often as they have not had much experience in helping patients (as they rarely use it). 

In our experience, for many women suffering from low T3, a lifetime of weight gain, reduced cognitive capacity, fatigue, high cholesterol and increased risks of diabetes and heart disease seems inevitable with the current approach. 

How does the Functional Medicine approach Differ? 

As with any autoimmune or metabolic disorder presented to us, the doctors at Functional Nexus always look for the root cause of any health concern.  

Our approach is holistic and detailed.  

Some of the ways we differ in our approach to thyroid health include – 

Comprehensive Testing: 

We consider Thyroid disease to be so common and so important that we screen ALL of our new 1-1 clinic patients for thyroid problems, including measuring: 

• Thyroid Stimulating Hormone (TSH) – This will usually go up if there is not enough thyroid hormone being produced. 

• Levothyroxine (Free T4) – This is the inactive thyroid hormone and is the primary hormone produced by the thyroid gland in response to TSH. 

• Liothyronine (Free T3) – This is the active thyroid hormone responsible for helping to improve metabolism and energy production. 

• Thyroid antibodies – These may be raised if there is an autoimmune disease attacking the thyroid gland. 

• Reverse T3 – This is used as a marker of secondary Thyroid hormone metabolism (and conversion of T4 to the active T3). 

In addition, if a patient is found/known to be hypothyroid, we can also offer screening for:  

• Urine iodine – To check for iodine deficiency (the most common cause of goitre or thyroid swelling). Due to deficient diets, iodine deficiency is common and low maternal iodine has been linked to reduced IQ in babies. ⁸ 

• Small Intestinal Bacterial Overgrowth (SIBO) – This abnormal change in the gut microbiome is a known reversible cause of secondary hypothyroidism. ⁹ 

• Urine Oxalate Screening – These tiny and destructive crystals can result in toxic damage to the thyroid gland. ^10,11 

For patients with poor T4 to T3 conversion, we consider why this might be happening and offer screens for: 

• Selenium deficiency – Low selenium can prevent T4 to T3 conversion and result in low T3 despite high T4 levels. ¹² 

• Heavy Metals Toxicity – Mercury in particular, can act as a trigger for Thyroid autoimmune disease, toxic hypothyroidism and suppression of T4 to T3 conversion. ¹³ 

• Adrenal Dysfunction – Individuals with high cortisol levels may develop elevated TSH ^14, and those with low cortisol levels due to adrenal dysfunction may experience poor T4 to T3 conversion. ¹⁵ Checking Cortisol where adrenal dysfunction is suspected helps us to safely manage patients with complex thyroid problems. 

• Deiodinase Enzyme variant screening – The Deiodinase enzyme which converts T4 to T3 can vary from person to person and some people have genetic variants which reduce T3 production. This is linked with higher risks of mental health issues and Alzheimer’s disease and is thought to be one of the reasons why some patients respond better to T4/T3 combination therapy. ¹⁶ 

Early intervention for Autoimmune thyroid disease with normal or borderline hormone levels: 

Instead of waiting for the thyroid hormone to get low enough to consider replacement therapy, we offer screening and interventions to try to restore thyroid function and reduce autoimmunity.  

This includes assessment and interventions for: 

• Nutritional status – Levels of B-Vitamins, iodine, iron, vitamin D, selenium, magnesium, zinc and essential amino acids are essential for proper functioning of the thyroid gland.¹⁷ After testing, we offer correction of any deficiencies with nutritional support. 

• Microbiome – Where we find significant dysbiosis or SIBO, we aim to treat the problem as this can help improve thyroid function. ⁹ 

• Elimination of dietary triggers for inflammation –  There is a well-known correlation between gluten sensitivity and Autoimmune thyroid disease. ¹⁸  

However, we (and a large number of other Functional Practitioners worldwide) also see high rates of dairy and soy sensitivity in our Thyroid patients. ¹⁹   

While gluten/ dairy and soy-free diets have not been found to reduce thyroid antibodies over short trial periods, we have noted improvements in antibody levels when this is continued over 12-18 months in many (but not all) of our Thyroid patients. 

Early thyroid support/replacement in women trying to conceive:  

The one group of patients we always offer early thyroid replacement to (while working on other root causes) is women who are actively trying to conceive or are undergoing IVF.  

In this cohort, we know that levels of TSH above 2.5 are associated with lower levels of fertility. ²⁰ Under the expert guidance of our consultant Endocrinologist, Dr La Rosa, we offer these patients early Levothyroxine replacement with the goal of TSH suppression to under 2.5. We also offer complete nutritional and dietary optimisation for women with fertility issues / trying to conceive. 

Hormonal support for persistent low T3, which doesn’t respond to metabolic support, and patients who remain symptomatic on T4 

In line with the current Joint British Thyroid Association / Society for Endocrinology guidelines, we offer a trial of T3 therapy to patients who have not responded to T4 only or who remain symptomatic despite optimisation with T4 and our guided attempts to improve T4 to T3 conversion. ²¹ 

We only offer T3 alongside the full investigation of possible alternative causes of symptoms while trying to address and treat potentially reversible causes of poor T4 to T3 conversion. All patients are fully counselled about the possible side effects of adding T3. However, we feel that patients deserve an informed choice in their care and have seen very positive benefits of T3 therapy in a wide range of patients. 

Lifestyle interventions 

As with any Functional Nexus treatment plan, we scrutinise and holistically offer support to help with associated symptoms such as weight gain, hair loss, low mood, anxiety, insomnia and constipation. 

Diet optimisation, nutritional supplementation where needed, help for sleep, stress management and an effective movement plan are all part of our standard therapy to help you with thyroid problems. 

To learn more about our nuanced approach and investigation of any health issue, including thyroid problems , do GO HERE.

Our experienced patient care team is ready to talk with you to see how we can help you optimise your thyroid health.