2. Poor diet (especially one lacking in iodine and selenium)
A diet low in nutrient-rich foods, especially in iodine and selenium (which are trace minerals crucial for thyroid function), increases the risk for hypothyroid disorders. The thyroid gland needs both selenium and iodine to produce adequate levels of thyroid hormones. These nutrients also play other protective roles in the body. For example: severe selenium deficiency increases the incidence of thyroiditis because it stops activity of a very powerful antioxidant known as glutathione, which normally controls inflammation and fights oxidative stress. Getting on track with a hypothyroidism diet ensures that you get the appropriate amounts of selenium and iodine in your diet.
3. Hormone imbalances
In some rare cases, because the pituitary gland makes a hormone called thyroid-stimulating hormone (TSH) — which controls the levels of hormones being pumped out of the thyroid — a problem with the pituitary gland can cause changes to thyroid function.
4. Gut inflammation (Leaky Gut Syndrome)
An unhealthy gut environment can contribute to nutrient deficiencies and raise autoimmune activity in the body. Food sensitivities or allergies, including those to gluten and dairy, can trigger gut inflammation. Other causes of a damaged gut are high stress levels, toxin overload from diet and the environment and bacterial imbalances. When leaky gut occurs, small particles that are normally trapped inside the gut start to leak out into the bloodstream through tiny openings in the gut lining, which creates an autoimmune cascade and a series of negative symptoms.
Although it’s not very common, newborns are sometimes born with a dysfunction of the thyroid gland, a genetic condition called congenital hypothyroidism. Some evidence shows that people are more likely to develop hypothyroidism if they have a close family member with an autoimmune disease. But according to the National Institute of Health (NIH), the likelihood of congenital hypothyroidism is very low and only about 1 out of every 4,000 newborns is born with a thyroid disorder.
During or following pregnancy, although it’s not exactly known why, some women begin to produce very high levels of thyroid hormones, followed by a very rapid decline. This condition is known as postpartum thyroiditis. The symptoms often disappear within 12–18 months but can also lead to permanent hypothyroidism.
7. Interactions of certain medications
Specific medications seem to lead frequently to the development of underactive thyroid. The most common of these include drugs to treat cancer, heart problems and certain psychiatric conditions.
8. High levels of emotional stress
Stress impacts hormones and is known to worsen inflammation. Stress can raise levels of cortisol and adrenaline, which disturbs neurotransmitter function and worsens symptoms of thyroid disease. These include low energy levels, poor mood, low concentration, disturbed appetite and weight gain and the inability to get restful sleep.