Menopause and thyroid function

Photo: Public Domain Pictures. Design: BOOST Thyroid.

Photo: Public Domain Pictures. Design: BOOST Thyroid.

How Hashimoto’s impacts the decline of sex hormones

A person will spend about 30 years of their life in menopause—experiencing a change in their health and quality of life because of low levels of the hormone estrogen.

Some symptoms of menopause overlap with symptoms of an underactive thyroid: fatigue, problems with focus and memory, anxiety, and muscle pain.

If hypothyroidism is not properly treated during menopause, symptoms from both low sex hormones and the thyroid condition will be amplified. This can result in a severe set of symptoms debilitating a person’s day-to-day life and work capacity.

Thyroid function during menopausal transition

Menopause is the permanent cessation of the menstrual cycle—officially recognized after a year of no menstrual cycles. It’s a normal physiological process as people age. 

When people reach their 50s, the ovarian reserve (number of eggs remaining in the ovaries) typically becomes low. This leads to low estrogen levels, which can’t support ovarian follicle growth,and affects many aspects of wellbeing (1).

The menopausal transition starts with menstrual cycles becoming longer. This changes the entire hormonal balance in the body, including the thyroid hormones. The thyroid becomes less able to produce the same amount of T4 and T3, while rT3 (reverse T3) levels increase. With age, the thyroid gland becomes flatter and has less output power. Less iodine is transported from the bloodstream and as a consequence the thyroid makes less T4. Also, the process of converting T4 to T3 takes longer too (2). 

So even if a person never had any issues with their thyroid gland, they might start experiencing some thyroid-related symptoms in their older age (4).

Why do menopausal symptoms occur?

Menopausal symptoms arise when the ovaries no longer produce adequate levels of the sex hormones estrogen and progesteron (5). Every fourth person in menopause will have some grade of an underactive thyroid (2).

Symptoms triggered by menopause will be intensified if the thyroid is not producing enough hormones (3). 

Lack of sex hormones during menopause impact a lot of things (6):

  • Ability to burn fat

  • Muscle mass

  • Lubrication of the vagina

  • Skin elasticity

  • Bone strength

  • Heart health

  • Thyroid output

  • Cholesterol levels (“bad” levels will be increased)

  • Body edema (water retention)

  • Bowel motility

  • Increased depressive mood

Thyroid therapy in menopause

L-Thyroxine (Synthroid) is the first line of therapy for menopausal people with an underactive thyroid. The dose might be adjusted depending on heart health, use of tobacco, and the fitness of each person (7).

Generally if you’re taking sex hormone replacement therapy, you might need a higher dose of thyroid medication.

Current treatment recommendation (8):

  1. People 50–70 years old with TSH levels between 1.0 and 3.0 mIU/L

  2. People 70+ with TSH levels between 2.0 to 5.0 mIU/L

Overtreatment with L-thyroxine for menopausal people can lead to excessive bone loss and heart problems (and at a faster pace than overtreatment in people with regular menstrual cycles) (7,9).

Menopause and Hashimototo’s

The immune system undergoes changes during menopause (10). 

Sex hormone levels decrease—which changes the number and type of immune cells, likely triggering the production of molecules responsible for inflammation (11 - 13). This increase in molecules promoting inflammation in the body can trigger Hashimoto’s in people that didn’t have it before, or increase the intensity of Hashimoto’s flare-ups in already diagnosed people (14, 15). 

Thyroid nodules and cancer in menopause

Thyroid nodules are five times more frequent in menopausal people than in younger people (6) and the risk of developing thyroid cancer is higher during menopause (7).

Diagnosis might take longer because people in menopause experience a lot of symptoms that might not specifically relate to thyroid problems (9).

People undergoing menopause with an untreated underactive thyroid have a higher risk of developing diabetes type 2 (16).

Here are thyroid symptoms to be on the lookout for (2):

  • Memory loss

  • Depression

  • Fatigue

  • Weight gain

  • Muscle pain 

  • Weakness

If you’re entering menopause and feel like your symptoms have intensified, track what you’re experiencing in BOOST Thyroid. This will help you and your doctor quickly figure out  what type of treatment you might benefit from.


  1. Peacock K, et al. Menopause, 2019

  2. Schindler AE. Thyroid function and postmenopause, 2003

  3. Hernández Valencia M, et al. Hypothyroidism associated to menopause symptoms worsening change with thyroid substitution therapy, 2008

  4. Mariotti S, et al. The ageing thyroid, 1995

  5. Panda S, et al. Analyzing Thyroid Dysfunction in the Climacteric, 2018

  6. Zhu BT, et al. Functional role of estrogen metabolism in target cells: review and perspectives, 1998

  7. Gietka-Czernei M. The thyroid gland in postmenopausal women: physiology and diseases, 2017

  8. Burch HB, et al. A 2013 survey of clinical practice patterns in the management of primary hypothyroidism, 2014

  9. Uygur MM, et al. Thyroid disease in the perimenopause and postmenopause period, 2018

  10. White HD, et al. CD3+ CD8+ CTL activity within the human female reproductive tract: influence of stage of the menstrual cycle and menopause, 1997

  11. Gameiro CM, et al. Menopause and aging: changes in the immune system—a review, 2010;

  12. Gameiro C, et al. Changes in the immune system during menopause and aging, 2010

  13. Chen Y, et al. Difference in leukocyte composition between women before and after menopausal age, and distinct sexual dimorphism, 2016

  14. Sammaritano LR. Menopause in patients with autoimmune diseases, 2012

  15. Nussinovitch U, et al. The role of gender and organ specific autoimmunity. Autoimmun Rev, 2012

  16. Jayanthi R, et al. Thyroid status in premenopausal and postmenopausal women - A biochemical study on insulin resistance in non obese, overweight and obese type 2 diabetics, 2018

Clar McWeeney