Of all glands in the endocrine system, the thyroid deserves special attention. Shaped like a butterfly and sitting either side of the windpipe at the front of the neck, the thyroid gland could be described as the body’s regulator as the hormones it secretes play an important role in metabolic processes, which help regulate energy, cell growth and tissue development. It is the significant incidence of thyroid disorders, along with the far-reaching effects of even minimal dysfunction, which means it is worth looking at this major player in our overall wellbeing.
If the thyroid becomes imbalanced – either over or underperforming – the whole body is affected.
Hypothyroidism (underperforming thyroid) affects virtually all cells and body functions. Symptoms can range from being so mild they are not detectable, to so severe and extreme that they are life threatening. Utilisation of fat, protein and carbohydrate is decreased; weight gain is common, as is sensitivity to cold weather, often with cold hands and feet; depression may occur, paired with weakness and fatigue, which can progress to concentration difficulties and forgetfulness.
Hypothyroidism essentially results from an under secretion of thyroid hormones – the two main ones being thyroxine (T4) and tri-iodothyronine (T3). This may be due to several factors, such as insufficient supporting nutrients to produce the necessary hormones, prolonged over-functioning of the thyroid gland, or Hashimoto’s disease. An autoimmune disease, Hashimoto’s causes an inappropriate immune response, where the body essentially “attacks” itself.
With hyperthyroidism, the cells of the body are exposed to an excess of thyroid hormones. This imbalance in thyroid function may result in an accelerated rate of bone loss along with cardiovascular consequences. Symptoms can vary but generally include nervousness and irritability, insomnia, weight loss, palpitations and increased heart rate, diarrhoea, fatigue, muscle weakness and changes in appetite.
In extreme cases, the eyes may begin to protrude, known as exophthalmos. The most common cause of hyperthyroidism is Graves’ disease, an autoimmune condition that causes an overproduction of thyroid hormone.
Thyroid disorders are seen much more commonly in women than men. For women, the menstrual cycle is often shorter with prolonged and heavy menses, leading to fertility issues. Physical signs are dry, rough skin and coarse hair, which is dry and brittle. Excess hair loss is common and nails may become thin and brittle. Cardiovascular problems may also arise with hypertension, alongside reduced heart rate and function.
Goitre is an enlargement of the thyroid gland, common in hypothyroidism, which is a result of the gland compensating for its underperformance. Certain foods are considered goitrogenic – that is, they disrupt the production of thyroid hormones by interfering with iodine uptake in the gland – and should always be avoided in hypothyroidism. These foods include raw vegetables from the brassica family, such as cabbage, kale, broccoli and cauliflower.
In pregnancy, the requirement for thyroid hormone increases, which needs to be met by adequate iodine intake. Increasing iodine, as well as supporting nutrients listed opposite, will reduce the risk of gestational hypothyroidism.
Due to the sensitive and reactive nature of the thyroid gland, seeking the guidance of a health practitioner is always recommended, particularly when medication is involved.
In order to stay healthy, exercise stimulates thyroid secretion and increases cellular sensitivity to thyroid hormones, making them more available for use. There are also a number of nutrients necessary for healthy thyroid function.
Zinc deficiency will lead to an underactive thyroid due to the vital role it plays in not only manufacturing thyroid hormones but also in them being recognised and utilised by cells. Keeping zinc levels high will help to support optimum thyroid function. Foods such as oysters, pumpkin seeds and toasted wheat germ provide good levels of zinc.
Iodine is essential for the proper functioning of the thyroid gland. Most Western diets have sufficient iodine, so it is important to check with your doctor before taking supplements. Too much iodine can also cause disturbances in thyroid function and should be avoided in cases of hyperthyroidism or hypothyroidism. Iodine is found in seafood, seaweed (kelp), eggs, bread, some vegetables and iodised salt.
Selenium and Copper
These minerals are both required for the conversion of thyroid hormones, essential in a healthy gland. Both selenium and copper are found in brazil nuts, sunflower seeds and oysters.
Tyrosine is an amino acid that works with iodine to make thyroid hormones, and it is essential to the proper functioning of the thyroid gland. Fish and poultry such as chicken and turkey are rich sources of tyrosine. Yoghurt and cottage cheese also provide goods amounts, as do legumes.
Including high amounts of antioxidants in your daily diet is vital to healthy thyroid function as it will help reduce the toxic load on such a reactive gland. Eating a plant-based diet with a variety of seasonal fruits and vegetables will support thyroid function.
What to eat
Cabbage, when consumed raw, is goitrogenic, as it contains a chemical that blocks the thyroid’s ability to use iodine. It should be avoided in hypothyroidism, however may play a role short-term role in calming an overactive thyroid.
Brazil nuts are high in selenium, a mineral essential to healthy thyroid function. Providing supportive co-factors such as selenium improves the production of thyroid hormones.
Seaweed is rich in iodine. Eating seaweed is beneficial in treating in hypothyroidism but due to its stimulating effect, should be avoided in hyperthyroidism.
Lemon balm can be consumed as a tea. It inhibits the production of thyroid hormones, having a calming effect on an overactive thyroid and so is useful in hyperthyroidism.
Soy is so effective at reducing thyroid function that it is contraindicated in hypothyroidism. Used short term, it has been shown to improve hyperthyroidism. Try a side dish of edamame or tofu for a tasty vegetarian meal.
Cauliflower can contribute to a reduction in the function of the thyroid gland when consumed raw. So it is best avoided in
hypothyroidism. It has been shown to calm an overactive thyroid for short-term relief.