Think it’s menopause? Your thyroid could be the real culprit

When we're in our 40's or 50's and we start experiencing common symptoms like weight gain, fatigue, anxiety, brain fog, joint pain, hair loss or temperature changes, the most logical assumption is that this is down to menopause.

But these symptoms are also identical to those associated with low thyroid hormones. This means that it might not be your sex hormones driving your symptoms (especially if conventional strategies are not helping). It might in fact be your thyroid. 

What is the thyroid? 

Your thyroid is a small, butterfly-shaped gland in the front of your neck, sitting just below your Adam’s apple. It’s part of your body’s hormone-producing system. The thyroid regulates your body’s metabolism and operates a bit like a thermostat.  Thyroid hormones travel to every cell in our body and regulate how much energy these cells produce. So they have the ability to affect every bodily process. It is therefore no surprise that when your thyroid begins to under function, you can feel drained of energy and unwell.

What can go wrong?

Hormonal changes (such as those occurring in perimenopause and menopause) can trigger thyroid dysfunction. According to the British Thyroid Foundation [1], it is common for perimenopausal and menopausal women to also have an underactive thyroid. Thyroid conditions do predominantly affect women; their incidence is 5-20 times higher in women than in men [2].  The thyroid can be either underactive or overactive, but low thyroid hormone levels are much more common [1]. Blood tests are required to assess thyroid function, some of which are available through the NHS. 

Another factor to consider is stress. Excess cortisol (our stress hormone) decreases thyroid hormone production [3]. Women in mid-life are often under a significant load of stress with managing teenagers, supporting elderly parents, and holding senior and demanding roles at work, alongside navigating hormonal changes. These high levels of stress can therefore also have a negative effect on our thyroid function.

Key thyroid nutrients 

There are 3 key nutrients shown to support optimal thyroid function: iron, selenium and iodine. The ideal is to get these through your diet

Selenium

Selenium activates enzymes that convert the inactive form of thyroid hormones (T4) to the active form (T3) in our bodies. Probably the best food source of selenium is Brazil nuts (you could try eating 1-2 nuts daily), although meat, seafood, eggs and cereals are also good sources. 

Iron 

Iron is also vital for the conversion of T4 into T3. When you don’t have enough iron, this process slows down, which can leave you tired and affect your metabolism. Iron deficiency can interfere with how your thyroid uses iodine and turns the iodide from food into usable iodine. Low iron is often the main cause of fatigue and hair loss. Animal based sources of iron (red meat, liver) are typically more bioavailable than vegetable sources (legumes, leafy greens and apricots).

Iodine

Iodine is essential for making thyroid hormones, but getting the right amount can be tricky without guidance. Too much iodine can interfere with thyroid function and make autoimmune thyroid issues and hypothyroidism worse [1]. This is not usually a problem with food sources, although it’s best not to overdo kelp/seaweed, which contains very high and unpredictable levels of iodine, which may lead to excessive iodine intake. Better balanced food sources include fish, shellfish, dairy, and eggs.

Key take home message

As you move through perimenopause and menopause, it’s easy to assume every new symptom is simply “hormonal.” But your thyroid plays a powerful role in how you feel day to day, and its symptoms often overlap with midlife changes. Understanding this connection can help you make sense of what’s going on in your body and feel more in control of your health.

Supporting your thyroid through balanced nutrition, managing stress, and staying aware of key nutrients like selenium, iron, and iodine can make a meaningful difference. And if your symptoms persist or don’t respond to the usual menopause-focused approaches, it may be worth exploring whether your thyroid needs attention.

Midlife is a time of transition, but it doesn’t have to be a time of mystery. The more you understand your body, the better equipped you are to advocate for yourself and feel your best through this chapter and beyond.  If you need more support for your thyroid or would like to explore your thyroid health through lab testing, please do get in touch.

REFERENCES:

[1] British Thyroid Foundation.(2023). Thyroid and menopause. https://www.btf-thyroid.org/thyroid-menopause.

[2] Gietka-Czernel M. (2017). The thyroid gland in postmenopausal women: physiology and diseases. Przeglad Menopauzalny = Menopause Review, 16(2), 33–37. https://doi.org/10.5114/pm.2017.68588

[3] Norman, S. J., Carney, A. C., Algarin, F., Witt, B., Witzel, I. M., Rodriguez, P. M., & Mohyeldin, M. (2024). Thyroid dysfunction and bipolar disorder: a literature review integrating neurochemical, endocrine, and genetic perspectives. Cureus, 16(9), e69182. https://doi.org/10.7759/cureus.69182