The thyroid

The thyroid is a small, butterfly-shaped gland located in the front of the neck. It has two lobes (right and left) connected by a narrow piece of tissue called the isthmus and it is located in front of the trachea (windpipe). The thyroid produces a thyroid hormone called thyroxine (T4 – 4 iodine atoms) which is converted to triiodothyronine (T3 – 3 iodine atoms). T3 is biologically active and regulates many bodily functions.

If our body detects that these thyroid hormones are too low, the pituitary gland in our brain releases another hormone called thyroid-stimulating hormone (TSH). These hormones play a crucial role in regulating the body's metabolism, energy production, and overall hormonal balance.

How to test thyroid function

A thyroid blood test is used to check thyroid function. The thyroid function test looks at the three thyroid hormones, TSH, T4 and T3 to determine whether your thyroid is working well (euthyroid), underactive (hypothyroidism) or overactive (hyperthyroidism). It is always a good idea to test for all these hormones rather than just TSH to get a better picture about what is going on in the body. Alongside thyroid hormones are thyroid antibodies these are tested to determine whether an autoimmune disease like Hashimoto’s or Graves’ disease is present.

Thyroid hormones – Normal levels and units

Source – British Thyroid Foundation 

Hypothyroidism (Underactive Thyroid) is mostly seen in women between the ages of 40-50 and is seen in women ten times more often than men, and it often occurs during the menopausal years. Hyperthyroidism (overactive thyroid) is less prevalent in the population.

Thyroid UK 

What causes thyroid problems

There are many reasons why the thyroid might experience dysregulation. Below are some examples:

  • Autoimmune disorders: Such as Hashimoto's Thyroiditis or Graves' Disease
  • Iodine deficiency: Iodine is essential for thyroid hormone production. A deficiency can result in hypothyroidism and goitre (enlarged thyroid gland).
  • Thyroid surgery: Removal of part or all of the thyroid gland can lead to hypothyroidism due to a decreased ability to produce thyroid hormones.
  • Radiation therapy: Radiation treatment for cancers of the head and neck can damage the thyroid gland, potentially leading to hypothyroidism.
  • Medications: Certain medications, such as lithium (mood stabiliser) and amiodarone (anti-arrhythmic) can interfere with thyroid function and cause hypothyroidism or hyperthyroidism.
  • Genetic factors: A family history of thyroid disorders can increase the risk of developing similar conditions.
  • Thyroid nodules: Benign or malignant lumps in the thyroid gland can affect its function, sometimes causing hyperthyroidism or requiring surgical intervention that leads to hypothyroidism.
  • Pregnancy and postpartum changes: Pregnancy can sometimes trigger thyroid problems, particularly postpartum thyroiditis, which can cause temporary hyperthyroidism followed by hypothyroidism.
  • Pituitary disorders: The pituitary gland regulates thyroid function through thyroid stimulating hormone (TSH). Disorders of the pituitary can affect thyroid hormone levels.
  • Infections and inflammation: Infections or inflammatory conditions affecting the thyroid (thyroiditis) can disrupt its normal function causing either hypo- or hyperthyroidism.
  • Diet and lifestyle factors: Poor diet, stress, and lack of sleep can indirectly affect thyroid health by influencing overall hormonal balance and immune function. 
Tired women

Underactive thyroid

An underactive thyroid is when the thyroid isn’t producing sufficient thyroid hormones, this is called hypothyroidism. If you have hypothyroidism or are wondering if you do, you will likely have experienced a few of the following symptoms: 

Early signs of hypothyroidism (Underactive thyroid)

  • Fatigue
  • Persistent tiredness and a general lack of energy
  • Weight gain
  • Feeling unusually cold or having an intolerance to cold temperatures.
  • Dry skin and hair
  • Constipation
  • Muscle weakness and aches
  • Depression
  • Memory issues
  • Slowed heart rate
  • Puffiness, especially around the eyes 

If you are experiencing these symptoms, it is recommended to go to your GP for a blood test to check your thyroid hormone levels.

If you do have hypothyroidism then you will have an elevated TSH level with low T4 levels. Around 2 in 100 people have hypothyroidism in the UK (Source – Hypothyroidism – Thyroid UK).

However, you might find your TSH levels are elevated but your T4 is normal, this is called subclinical hypothyroidism which affects around 8-10% of the population (Source – Hypothyroidism – Thyroid UK). In other words, it's a mild form of hypothyroidism where the thyroid hormone levels are still within the normal range, but TSH levels are elevated. 


  • Autoimmune conditions like Hashimoto's and lack of Iodine.
  • Pregnancy due to hormonal changes 


To treat hypothyroidism, a form of hormone replacement therapy called Levothyroxine is a synthetic thyroxine (T4) is used. This medication normalises hormone levels and alleviates symptoms.

Pink Scale

Why is it difficult to lose weight with hypothyroidism?

Losing weight with hypothyroidism is often more challenging than without. Here are a few reasons why it can be harder:

  • Slowed metabolism: Thyroid hormones (T3 and T4) play a crucial role in regulating metabolism
  • Fatigue and low energy levels: Reduced motivation and capacity to exercise regularly can lead to fewer calories being burned
  • Water retention: Retaining water leads to bloating and weight gain that is not related to fat
  • Appetite and food cravings: Hormonal imbalances can affect appetite and lead to increased cravings for high-calorie foods, particularly carbohydrates and sugars.
  • Insulin resistance: Decreased insulin sensitivity can lead to higher blood sugar levels and increased fat storage, particularly around the abdomen.
  • Mood and mental health: Exacerbating depression and anxiety, which can impact eating habits, physical activity, and overall motivation.
  • Slower digestive function: Constipation and gastrointestinal discomfort

Overactive thyroid

The opposite of hypothyroidism is hyperthyroidism. This is when the thyroid gland produces excessive amounts of thyroid hormones. Blood tests can show a suppressed TSH level and elevated T4 and T3 hormones.

Early warning signs of overactive thyroid:

  • Weight loss
  • Feeling unusually warm or sweating excessively
  • Rapid or irregular heartbeat
  • Nervousness and anxiety
  • Tremors
  • Increased bowel movements or diarrhoea
  • Fatigue and muscle weakness
  • Difficulty sleeping
  • Thinning hair or hair loss 


  • Autoimmune disorders such as Graves' Disease 
  • Inflammation of the Thyroid or postpartum thyroiditis.
  • Excessive Iodine Intake: Consuming too much iodine, either through diet or contrast dyes used in medical imaging tests can lead to hyperthyroidism. 



Carbimazole and Propylthiouracil - These medications inhibit the production of thyroid hormones by interfering with the thyroid gland's ability to use iodine.

Beta blockers such as Propranolol, Atenolol and Metoprolol -These medications help alleviate symptoms such as rapid heart rate, palpitations, tremors, and anxiety by reducing the heart rate.

Radioactive iodine therapy

Radioactive iodine is taken orally and selectively absorbed by the overactive thyroid cells and destroys them. This treatment is done once and gradually reduces thyroid hormone production over weeks to months. The downside is that this often results in permanent hypothyroidism, requiring lifelong thyroid hormone replacement therapy.


Partial or Total Thyroidectomy is the surgical removal of part of or all the thyroid gland.

This might be recommended for individuals who cannot tolerate medications, are not suitable for radioactive iodine therapy or have large goitres (enlarged thyroid gland). After a total thyroidectomy, thyroid hormone replacement therapy is necessary as the body can no longer make its own thyroid hormones. 

The thyroid during menopause and pregnancy


Women with hypothyroidism who are pregnant or planning to become pregnant need careful monitoring and may require higher doses of levothyroxine to support proper thyroid hormone levels. There is also a risk of postpartum thyroiditis that can happen to any pregnant woman. It starts off with hyperthyroidism for 1-4 months and then to hypothyroidism in months 4-8 postpartum. At around 12-18 months the thyroid hormones level out and euthyroid is established in most cases. Pregnancy can lead to hypothyroidism through conditions like postpartum thyroiditis or exacerbation of pre-existing autoimmune thyroid conditions. Diagnosing and managing hypothyroidism effectively during pregnancy is essential to ensure the health and well-being of both the mother and the developing foetus.

Women menopause


Menopause can influence thyroid hormone levels, leading to changes in thyroid function resulting in subclinical hypothyroidism or hypothyroidism. Some symptoms of menopause such as fatigue, weight gain, mood changes and memory problems can overlap with symptoms of hypothyroidism. It is essential for women experiencing these symptoms during menopause to undergo thyroid function testing to distinguish between menopausal symptoms and thyroid-related issues.

Menopause may also be associated with an increased risk of developing thyroid nodules or goitre (enlarged thyroid gland). Hormonal changes during menopause, particularly fluctuations in oestrogen levels, may contribute to thyroid growth or nodules.

Women with autoimmune thyroid disorders like Hashimoto's thyroiditis or Graves' disease may experience fluctuations in disease activity during menopause.



There are things we can do to protect our thyroid gland through the food we consume. The micronutrient Iodine is required to make the T4 and T3 hormones, therefore its intake is essential for thyroid function. Consuming foods high in iodine such as seaweed, dairy products and seafood and foods rich in selenium (Brazil nuts, sunflower seeds) and zinc (meat, shellfish) support thyroid function. 

If you already have thyroid problems avoid consuming soy products and cruciferous vegetables (broccoli, cabbage, cauliflower) in excess as they are goitrogenic and can interfere with thyroid function. You don’t have to avoid these foods but eat them in moderation; cooking these vegetables can reduce their goitrogenic effect.

Regular physical activity to help manage weight, improve mood, and boost overall energy levels. Engage in regular physical activity, including both aerobic exercises (like walking, running, cycling) and strength training exercises.

Aim for at least 150 minutes of moderate aerobic activity or 75 minutes of vigorous activity each week, along with muscle-strengthening activities on two or more days a week.

Incorporate more physical activity into your daily routine, such as taking the stairs instead of the elevator, walking during breaks, or doing household chores.

Woman yoga mats

Lifestyle Modifications

Sleep: Ensure you get adequate sleep, as poor sleep can disrupt hormones that regulate appetite and metabolism. Aim for 7-9 hours of quality sleep per night. 

Stress Management: Practice stress-reducing techniques such as meditation, yoga, deep breathing exercises, or engaging in hobbies. Chronic stress can affect weight and overall health. 

Support System: Seek support from friends, family, or a weight loss group. Having a support system can provide motivation and accountability. 

Saffrosun Energy Saffron Supplement

Thyroid Supplements

Alongside diet and lifestyle changes we might just need a little bit more support to keep our thyroid healthy. 

Our Saffrosun Energy contains Saffron, Vitamin D and Iodine. Saffron may support thyroid function through its anti-inflammatory, antioxidant, and immune management qualities, as well as by improving mood and metabolic health.

Vitamin D supports the thyroid gland by regulating hormone production, regulating the immune system, reducing inflammation, supporting calcium balance and potentially reducing the risk of autoimmune thyroid diseases. And finally, Iodine is key for thyroid function, supporting the synthesis and regulation of thyroid hormones, preventing goitre and ensuring proper growth and metabolic regulation.

We don’t recommend this supplement for anyone with hyperthyroidism. However, those with hypothyroidism, those taking thyroid replacement therapy or those with normal thyroid function can.

Saffrosun Calm is an alternative for those with hyperthyroidism. It contains Saffron, Vitamin D and Vitamin B12. The benefits of Saffron and Vitamin D on the thyroid can still be experienced.


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Charlotte Parker-Lennox

Charlotte Parker-LennoxCharlotte is a pharmacist with 6 years of experience working in retail pharmacy and integrated urgent care (IUC) alongside nurses, paramedics and doctors. She has changed the direction of her career to support people with a holistic approach to wellness by treating the root cause of your health concerns. She enjoys an outdoor challenge, completing marathons and cycling adventures around the UK.