Your thyroid is a butterfly shaped gland in your neck. It produces hormones that are labeled on blood tests as T3 and T4. These hormones are needed for all cells in your body to function normally. Your thyroid specifically regulates your metabolism, growth and development. It also has a key role in regulating cholesterol and blood pressure. Thyroid issues lead to inflammation and physical stress on the body which can also worsen heart disease issues.
*Warning Science Bit* The thyroid makes two hormones that it secretes into the blood stream. One is called thyroxine; this hormone contains four atoms of iodine and is often called T4. The other is called triiodothyronine, which contains three atoms of iodine and is often called T3.
The thyroid gland produces hormones that regulate the body’s metabolic rate controlling heart, muscle and digestive function, brain development and bone maintenance. Its correct functioning depends on a good supply of iodine from the diet. Cells producing thyroid hormones are very specialised in extracting and absorbing iodine from the blood and incorporate it into the thyroid hormones.
The pituitary gland (located at the bottom of your brain) is responsible for the release and production of thyroid hormones. It sends out a hormone called TSH to tell the thyroid gland how much hormones to make and secrete.
If too much of the thyroid hormones are secreted, the body cells work faster than normal, and you have hyperthyroidism. If too little of the thyroid hormones are produced you have hypothyroidism, in hypothyroidism the cells and organs of your body slow down.
Hypothyroidism is the most common thyroid problem, accounting for approximately 80% of thyroid issues.
Other thyroid conditions include goitre (swelling of the thyroid gland), autoimmune thyroid issues such as Graves Disease where autoimmune condition in which the thyroid is overstimulated, causing hyperthyroidism. Hashimoto’s Thyroiditis is a genetic autoimmune condition that damages the thyroid gland causing hypothyroidism.
Symptoms of Hypothyroidism:
- High Cholesterol
- Sensitivity to cold
- Weight gain – including weight loss resistance
- Depression, anxiety or low mood
- Slow movements and thoughts
- Muscle aches and weakness
- Muscle cramps.
Symptoms of Hyperthyroidism:
- Nervousness, anxiety and irritability
- Hyperactivity – you may find it hard to stay still and have a lot of nervous energy
- Mood swings
- Difficulty sleeping
- Feeling tired all the time
- Sensitivity to heat
- Muscle weakness
- Needing to pee more often than usual
- Persistent thirst
- Loss of interest in sex
(source NHS 2020)
Thyroid Problems in Women
Thyroid conditions affect women more often than men, in fact women are 5 to 8 times more likely to develop a thyroid condition. Goitre (swelling in the neck) is often one of the first visible signs of a thyroid issue. Other signs include:
- Change in energy – while a hypothyroid problem can wipe you out and apathetic (whatever!), a hyperthyroid issue can make you feel wired and on edge.
- Change in bathroom habits – an under active thyroid can cause constipation, however if you have an overactive thyroid you make experience loose stools or diarrhoe.
- Change in concentration – women with low thyroid function may experience brain fog and memory problems while those with an overactive thyroid can find it difficult to focus and concentrate.
- Changes in your menstrual cycle – women with hyperthyroidism often experience fertility issues and scant or irregular periods, women with hypothyroidism often experience heavy menstrual periods and postpartum, hypothyroidism can reduce milk supply.
- Changes to hair skin and nails – those with an under active thyroid report brittle nails, loss of eyebrow hair, coarse or dry hair texture and dry skin, those with an overactive thyroid report hair loss and soft nails.
Hypothyroidism and High Cholesterol
One of the first clinical signs of a hypothyroid maybe high cholesterol, even in mild or sub-clinical underactive thyroid high LDL cholesterol is common.
Your LDL cholesterol exits your body using your liver. Thyroid hormones T3 is needed for cholesterol clearance by the liver. In hypothyroidism there is a low level of T3 and so cholesterol is not as efficiently removed leading to a high level of cholesterol in the body.
In addition to removing cholesterol from the body, thyroid hormones also regulate the absorption of cholesterol which can increase circulating cholesterol. High TSH levels can also increase LDL cholesterol.
Supporting your thyroid function can bring your cholesterol levels back into balance. However studies have shown that Levothyroxine (the most commonly used medication for hypothyroidism) may not bring cholesterol levels back into balance.
If this is the case, you may end up on a cholesterol lowering drug such as a statin. However these medications stop the absorbing essential vitamins including Vitamin A and E and stop the body from producing Co-Q-10 which is essential for energy production in heart muscles. Statin use is also associated with an increased risk of diabetes in people with an under active thyroid.
Some people with hypothyroidism can also experience high blood pressure, this is called secondary hypertension. Levothryoxine may not reduce your blood pressure and so you may be put on a blood pressure reducing medication by your doctor if you are unable to reduce it through nutrition and lifestyle changes.
Hyperthyroidism and Heart Disease
Excess thyroid hormone (hyperthyroidism) causes the heart to beat harder and faster and may trigger abnormal heart rhythms.
One is atrial fibrillation, a disorganised rhythm in the heart’s upper chambers. A related symptom is palpitations, a sudden awareness of your heartbeat.
People with hyperthyroidism may also have high blood pressure. In hyperthyroidism, blood vessels relax, lowering diastolic blood pressure (the second, or bottom, number in a blood pressure reading). But an excess of thyroid hormone also increases the force of the heart’s contractions, leading to an increase in systolic pressure (the first, or top, number).
In a person with clogged, stiff heart arteries, the combination of a forceful heartbeat and elevated blood pressure may lead to chest pain or angina.
If you have hyperthyroidism you may have low cholesterol levels. Having low cholesterol can increase your risk of heart disease and bleeding stroke.
Supporting Your Heart and Under Active Thyroid and
There are many ways to support your thyroid naturally through diet and lifestyle change. In all cases of thyroid problems, managing stress, lowering inflammation, the right level of exercise and getting adequate, restful sleep are critical.
Exercise can improve cardiovascular health and thyroid health. However, itcan be difficult in hypothyroidism due to low energy levels, high LDL cholesterol levels can also reduce your ability to do aerobic exercise. Here walking 20-35 minutes per day can make a significant difference. Rather than weight lifting, rebounding or yoga can help with cell energy and muscle build up.
In hyperthyroidism, exercise is particularly helpful. Medium to low intensity exercise such as walking (providing you don’t have swollen feet), aqua aerobics and strength training have been found to help manage the condition.
Foods for Hypothyroidism:
- Vitamin D and Vitamin D rich foods e.g. eggs which are also high in iodine
- Zinc rich foods e.g. beans, nuts, poultry, seafood, red meat
- Selenium e.g. Brazil nuts
- Protein including seafood, meat, poultry
- Seaweed (avoid iodine if you have Hashimoto’s Thyroiditis)
- B12 rich foods or supplements as this can become deficient due to medications
- Fibre rich vegetables particularly leafy greens (goitregenic foods should be well cooked and limited see list below)
Foods for Hyperthyroidism:
- Raw or lightly cooked goitregenic foods e.g. Brussel sprouts, kohlrabi, turnips, swede, radishes, cabbage, kale, and cauliflower
- Vitamin D rich foods or supplements
- Omega 3 rich foods e.g. oily fish, flax seed, pumpkin seeds
- Antioxidants e.g. berries, citrus fruits, red grapes, dark chocolate
- Calcium rich foods – green leafy veg, fortified plant milks, sardines and other small fish
- Probiotics and fermented foods due to gut issues associated with the condition
- L-Carnatine is an amino acid that has been shown in clinical studies to reduce blood pressure
It is often recommended that gluten and dairy be avoided by those with thyroid issues, particularly thyroid problems caused due to autoimmune conditions. This is a complex interaction and would need a separate blog to explain properly!