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How to Lose Weight with Hypothyroidism

By 25th September 2023Health Conditions
Lose Weight with Hypothyroidism


Hypothyroidism describes an underactive thyroid condition. This is where the thyroid is not producing the adequate amount of thyroid hormone. There are many possible causes and contributing factors to hypothyroidism, such as nutrient deficiencies and gut imbalances, but also immune aspects, such as autoimmune thyroiditis (Hashimoto’s). [Source: Mayo]

Many symptoms are associated with having an underactive thyroid. These are wide-ranging and can include:

  • Weight gain
  • IBS symptoms
  • Bloating
  • Constipation
  • Dry skin
  • Fatigue
  • Depression [Source: PubMed]

One of the most common symptoms of having an underactive thyroid that individuals notice is weight gain. This also means this is often one of the common symptoms (along with the symptoms of IBS) that patients with hypothyroidism want to address.

This can lead many with this hormonal condition to reduce calories and food intake to try to drop this weight. However, this is not always the right approach for all and can lead to individuals simply eating less and training more and more to regulate weight balance. 

Since the thyroid gland regulates metabolism, working to address the underlying reason for its underperformance is often the priority. [Source: PubMed]

Is it possible to lose weight when you have hypothyroidism?

Yes, it is possible to lose weight with hypothyroidism. However, there are key areas that need to be focused on to address this.

This can include:

  • ensuring appropriate calorie intake
  • optimising sleep and movement [Source: PubMed]
  • supporting the gut microbiome [Source: PubMed]
  • supporting the thyroid gland with the right supplements [Source: PubMed]

In the clinic, we find that most of our patients have already paid lots of attention to the food they’re eating by reducing the proportion of refined foods in their diet and increasing the proportion of processed, natural, and whole foods. This type of diet is often referred to as the Mediterranean diet.

From this foundation, we do see that many people have not focused on other areas such as sleep, the gut, and key thyroid nutrients. 

It’s also important to take into other areas that can impact the thyroid gland, such as:

  • Infections [Source: PubMed]
  • Toxicity [Source: PubMed]
  • Stress and emotional trauma [Source: PubMed]

Thyroid Gland DiseasesWill I lose weight on levothyroxine?

Levothyroxine is a synthetic hormone that is used as a replacement for thyroid hormone. While the underproduction of thyroid hormones is often caused by another factor (or combination of factors), replacing this hormone with a medication is often the main approach considered and used by medical doctors.

Because one of the main symptoms of having an underactive thyroid is gaining weight, supporting the levels of thyroid hormone can help with weight reduction and weight management. 

If excessive weight loss happens or weight loss continues, it may be that the dose of this thyroid medication is too high and needs to be adjusted by a doctor. [Source: NHS]

Will I lose weight once I start taking thyroid medication?

If you have hypothyroidism, it’s likely that your weight has been slowly creeping up over time. This also means that once the medication is started, you may not notice a change in the weight right away, and it may take time for weight to be lost. 

This loss of weight is usually gradual, and it depends on many factors.

These factors include:

  • how much thyroid hormone your body needs
  • how constantly you are taking the medication [Source: PubMed]
  • whether or not there are other health issues involved [Source: PubMed]
  • whether or not you’re exercising regularly [Source: PubMed]

If you don’t feel like you are losing weight from taking this medication, other areas may need to be assessed, such as gut health.

What to eat with hypothyroidism

In addition, reducing the intake of refined and processed foods is often the priority for any health condition. Ensuring a nutrient-dense and varied diet should be a foundation to support the thyroid gland. 

This is often referred to as the Mediterranean diet. This includes ensuring a wide variety of plant foods, good quality protein, and whole grains. [Source: PubMed]

Tracking calories isn’t something that I suggest doing over a long period of time. However, even a few days of tracking can provide some helpful information about whether you’re eating too much or even too little.

Can hypothyroidism cause a big stomach?

Hypothyroidism can cause weight gain. Eating a healthy diet and exercising regularly is important, but many of our patients are already following the foundational steps.

It can also be that an underactive thyroid can lead to alterations in the gut microbiome. Many with an underactive thyroid also experience constipation, one of the main symptoms of IBS. Along with the constipation, the gut symptoms can also include bloating or distention. In some, it is similar to weight gain, with clothes becoming tighter and more uncomfortable.

This is part of the reason why we focus on not just the thyroid but what is happening in the gut due to the link between these two areas of the body and how they influence each other. 

With changes in the gut microbiome altering and influencing the functioning of the thyroid gland.] This can be due to the reduction of key nutrients required for thyroid health and low levels of inflammation. [Source: PubMed]

Exercise to boost your metabolism with hypothyroidism

A common misconception about hypothyroidism is that it means you can’t lose weight. This isn’t true.

Exercise is still an important factor for weight loss even with hyperthyroidism; however, solely for that, focusing on weight loss and reducing calories is often not enough. It’s not uncommon for us to see patients where they’ve been exercising more and more and eating less and less and seeing no results.

This is where we want to focus on areas outside of the thyroid, such as the gut microbiome stress management, the quality of the diets, and other factors such as environmental chemicals or toxins. [Source: PubMed]

Causes of Weight Gain

Weight gain is a common symptom of hypothyroidism. 

This is due to one of the primary roles of the thyroid hormones to regulate metabolism. This process is responsible for burning energy within the body; therefore, if the thyroid is not functioning optimally, more energy is stored, and less is being broken down, resulting in weight gain.

This is also why one of the primary symptoms of an underactive thyroid is fatigue. This is due to the poor functioning of energy processes within the body, resulting in low energy output. [Source: PubMed]

What not to eat with hypothyroidism

Avoiding refined carbohydrates is a key focus when supporting thyroid health and any other health issue, for that matter. Refined carbohydrates, such as white bread and pasta, are quickly digested and absorbed by the body.

This means that they cause blood sugar levels to spike quickly. As a result, insulin is secreted in large amounts by your pancreas in order to lower these high levels of glucose (sugar). This can lead to blood sugar dysregulation and contribute to weight gain.

This is also true for more processed and refined simple sugar. These are found in processed foods such as candy bars or soft drinks; they are also added during food preparation (such as adding sugar or corn syrup to salad dressings).

These types of foods cause an immediate rise in blood glucose levels followed by rapid drops once they’ve been broken down into smaller units by digestion enzymes within the body. These types of foods can often be more related to snacking. Therefore, a very common suggestion we make is to avoid snacking as it can quickly cut out a high amount of refined and processed foods.

Additionally, other forms of highly processed foods can also be held to a minimum. These contain ingredients that aren’t found naturally occurring within nature and are used as preservatives, colouring agents, and flavour enhancers. [Source: PubMed]

Natural supplements for hypothyroidism

Instead of focusing solely on eating the appropriate amount of calories. Working to address possible underlying reasons for thyroid dysfunction is a central part of the approach.

This can include the usage of evidence-based, natural supplements. 

These include:

Vitamin D – low levels of vitamin D are commonly found in those with an underactive thyroid. It has also been found that the lower the levels of this vitamin, the more severe the hypothyroidism. [Source: PubMed]

Selenium – in those with Hashimoto’s thyroiditis, supplementing with this nutrient reduced the levels of thyroid antibodies. It also improved the structure of the thyroid when examined via ultrasound, indicating better thyroid health. [Source: PubMed]

Additional nutrients that can support thyroid health and function include:

  • Zinc
  • Vitamin A
  • Magnesium [Source: PubMed]


With any health condition, there are generally 2 aspects to the approach. The first is managing symptoms. For example, this can be removing foods if it’s causing bloating.

However, the second aspect of the approach is to address the underlying issue with the thyroid gland. These underlying issues can include a poor diet, high amounts of stress, lack of sleep as well as alterations in the gut microbiome.

To lose weight with an underactive thyroid, we want to address all of these factors where appropriate and create a personalised plan to support health, well-being, and lose weight.