An overactive or underactive thyroid can cause many unsavoury symptoms. The entire network of glands called the ‘endocrine system’ plays a vital role in regulating physical development and metabolic function (the way your body converts raw materials into energy and protein).
The thyroid doesn’t simply produce hormones by itself – there’s a complex chain of processes involved. One step in the chain is the conversion of T4 to T3. If this process is hampered, hormonal imbalance may result.
What are T4 and T3?
T4 is the thyroid hormone thyroxine, and T3 is the hormone triiodothyronine. All the cells in the human body depend on these hormones for healthy metabolic function. A normal-functioning thyroid gland produces far more T4 than T3, but T3 is the stronger and more active of the two.
T4 is converted into active T3 in multiple tissues and organs. When this process is hampered, you can have plenty of T4 present in your bloodstream but not enough T3 to keep hormonal balance. This in turn can lead to an underactive thyroid (hypothyroidism), even if the thyroid gland itself is working fine.
Factors that inhibit T4 to T3 conversion and how to address the problem
Many doctors will prescribe synthetic T4 supplements to people who have poor thyroid hormone function. Yet if the problem is conversion-related, this won’t solve it. These five factors can inhibit T4 to T3 conversion:
- Mineral deficiencies – Selenium and zinc are two minerals that play important parts in converting inactive T4 to active T3.
- Gastrointestinal disorders – Even if you’re getting sufficient minerals from your diet, gastrointestinal problems can impair absorption. There are also enzymes in the gut that are important in the conversion process.
- Liver issues – a large percentage of T4 to T3 conversion occurs in your liver, thus reduced detox ability in the liver can cause issues.
- Adrenal problems – High cortisol in your system caused by stress can contribute to T4 conversion being sub-par.
- Some medications – Propranolol, a beta blocker, can inhibit T4 to T3 conversion.
It can be tricky pinpointing which of these possible issues underlie a T4 conversion problem. A GP who works holistically with each element of wellbeing (physical and nutritional as well as mental) can help.
Nature’s medicine chest is rich with herbs such as Ashwaganda and Coleus that promote healthy metabolic function. A combination of stress reduction techniques and healthier eating will help you reduce cortisol and help change other possible factors. Contact Dr Alison today to find out what you can do to help improve your thyroid’s function.