The Link Between Thyroid Health and Weight

Weight gain is one of the biggest frustrations for people with thyroid disorders. The thyroid plays a crucial role in regulating metabolism, which directly affects weight management. Understanding this connection is essential for those looking to maintain a healthy weight or for those who are experiencing unexplained weight fluctuations.

What is The Thyroid & Why Is It Important to Weight Management

The thyroid is a small, butterfly-shaped gland that lives in the front of the neck, just below the Adam’s apple (Sanyal, & Raychaudhuri, 2016). Despite its small size, the thyroid plays a vital role in regulating a lot of functions in the body.

This small organ is so important because it creates hormones that help control metabolism, growth, and development throughout the body.

The hormones made by this organ are mainly triiodothyronine (T3) and thyroxine (T4), which both influence the body’s metabolism (Sanyal, & Raychaudhuri, 2016). These hormones control how the body uses energy, determine the rate at which calories are burned, and so have a big effect on weight management.

How Does An Underactive Thyroid Affect You?

When everything is working correctly with the thyroid, it creates the right amount of T3 and T4 to maintain a healthy metabolism.

However, when the thyroid is underactive, it does not make enough of these hormones (Sanyal, & Raychaudhuri, 2016).

This condition is known as Hypothyroidism and is the most common hormonal disorder worldwide, it affects around 350 million people, most of whom are women (Hogqvist Tabor et al., 2021).

Without treatment an underactive thyroid can lead to obesity, depression related disorders, and increases the risk of female infertility (Hogqvist Tabor et al., 2021).

Signs and Symptoms of an Underactive Thyroid: What You Should Know

Hypothyroidism, or underactive thyroid, can many different symptoms which can be mild or severe. Common signs include fatigue, weight gain, feeling cold, dry skin, hair changes, and constipation (Sanyal, & Raychaudhuri, 2016). It can also affect the heart, causing a slower heart rate and fatigue during exercise. Some women may experience menstrual irregularities and difficulty getting pregnant (Sanyal, & Raychaudhuri, 2016).

In rare severe cases it can lead to a life-threatening condition called myxedema coma, characterized by loss of consciousness and low body temperature. Treatment with thyroid hormone replacement can alleviate these symptoms (Sanyal, & Raychaudhuri, 2016).

How Does An Overactive Thyroid Affect Your Weight?

On the other hand, an over-active thyroid (hyperthyroidism) produces excessive amounts of T3 and T4, which can lead to a faster metabolism. This increased metabolic rate can cause weight loss, despite an increased appetite (Kyriacou et al., 2019).

Whilst hyperthyroidism usually causes weight loss, around 10% of patients may experience weight gain (Kyriacou et al., 2019).

The effect of treatment on weight can vary, but some studies suggest that it can lead to excess weight gain (Kyriacou et al., 2019).

But different treatments may have different effects, radioiodine and surgery have shown evidence of potentially leading to more weight gain than anti-thyroid drugs (Kyriacou et al., 2019).

Factors such as the severity of hyperthyroidism and underlying Graves’ disease can contribute to weight changes. Plus, some studies suggest that using that dietary interventions during treatment reduce the chances of weight gain during this process (Kyriacou et al., 2019). But more research is needed to understand the impact of different treatments and weight loss interventions on weight changes in individuals with hyperthyroidism (Kyriacou et al., 2019).

It’s important to note that a thyroid is not the only thing that determines body weight. Many things impact weight management, including diet, exercise, genetics, and overall health. So, any changes in weight related to thyroid dysfunction can often be managed effectively with appropriate medical treatment and lifestyle modifications.

Do Only Women Get Thyroid Issues?

Women are at higher risk of thyroid problems than men and conditions affecting the thyroid gland can affect women in different ways too.

The risk for women is about 10 times higher than for men. With 1 in 8 women being affected by a thyroid issues at some point in their lives.

One reason for this is that thyroid disorders are often triggered by autoimmune responses, which happen when the body’s immune system starts to attack its own cells.

Another reason for the prevalence of thyroid disorders in women is that there is an interplay between thyroid hormones and the hormones that fluctuate during the menstrual cycle. Thyroid problems can happen at any time, but they are especially common in women during and after the menopause when hormone levels are changing. This is why some women can confuse the symptoms of thyroid disorders with the effects of the menopause. This is a big problem as this confusion can prevent them from seeking treatment.

Worried You Might Have A Thyroid Issue?

Epicentre provides comprehensive and Thyroid testing at our Walk-In Lab. Why wait? Testing is easy, safe and affordable.

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