Why is hypothyroidism more common in women?

Thyroid problems can affect men, women, children, and even infants. However, by far the most commonly affected group is middle-aged and older women, with one in eight women likely to develop a thyroid disorder during her lifetime. This rate is five to eight times higher than the rate in men (1). So, the question is, why are rates so much higher in women?

First, let’s quickly go over the functions of the thyroid
The thyroid gland is a small organ located just under the skin in the neck. This bow tie-shaped organ is usually only about 5 cm across and normally can’t be felt or seen. The thyroid releases specific hormones (chemical messengers) that act on almost every tissue in the body (2). These thyroid hormones help regulate so many vital body functions, including:

  • Heart rate
  • Skin maintenance
  • Heat production
  • Fertility
  • Growth
  • Digestion
  • Rate at which calories are burned

What happens when the thyroid isn’t functioning properly?
Thyroid hormones influence so many different parts of the body, so when they are out of balance, lots of different symptoms can occur.

Hypothyroidism is an underactive thyroid, so it does not release enough thyroid hormones. This causes many of the body’s functions to slow down, causing symptoms like fatigue, slow heart rate, constipation, weight gain, and constantly feeling cold (3).

Hyperthyroidism is an overactive thyroid, so too many thyroid hormones are released into the bloodstream. This speeds up many of the body’s functions, causing symptoms like weight loss (even though appetite is increased), rapid or irregular heart rate, frequent bowel movements, sweating, and shaky hands (4).

To learn more about things that can affect your thyroid health, read our previous article here.

So, why are thyroid problems more common in women?
The risk of thyroid problems, in particular hypothyroidism, increases as a woman ages, as well as during pregnancy and the postpartum period (5). This is thought to be linked to the female hormone fluctuations that occur during each menstrual cycle, during pregnancy and the postpartum period, and especially the major hormonal changes that occur around menopause (6). Read our previous article here to learn more about the changes that occur at menopause.

Another reason for the increased risk of thyroid problems in women is because thyroid problems are often triggered by autoimmune responses, and these autoimmune responses are more common in women than in men (6).

What health problems in women are linked to thyroid disorders?
Thyroid problems in women are not only more common than in men, but they also can cause multiple additional symptoms. These symptoms can include:

  • Delaying or speeding up of puberty
  • Affecting period regularity and flow
  • Fertility issues
  • Premenstrual syndrome (PMS)
  • Increasing risk of ovarian cysts
  • Complications during pregnancy, including severe morning sickness, premature labour, or miscarriage
  • Earlier menopause

How can I get my thyroid function checked?
Checking the function of your thyroid is simple with a range of tests offered by us. Take our simple Thyroid Stimulating Hormone (TSH) Test for TSH alone, our Thyroid Health Panel to also include T4 and T3 along with TSH, or opt for the Thyroid Health, Complete Panel to also include Anti-Tg and Anti-TPO.

1. General Information/Press Room. American Thyroid Association.
2. Hershnan JM. (Modified Oct 2020). Overview of the Thyroid Gland. Merck Manual Consumer Version
3. Hypothyroidism (Underactive Thyroid). National Institute of Diabetes and Digestive Kidney Diseases. NIH. Reviewed March 2021.
4. Hyperthyroidism (Overactive Thyroid). National Institute of Diabetes and Digestive Kidney Diseases. NIH. Reviewed August 2021.
5. Dunn D & Turner C (2016). Hypothyroidism in Women. Nursing for Women’s Health. 20(1): 93-98.
6. Why Women Are More Prone to Thyroid Problems? The Harley Street Ear Nose & Throat Clinic. (March 2018).