Under functioning thyroid symptoms:
Fatigue, waking up unrefreshed, constipation, weight gain, foggy brain, difficulty focusing, dry skin, cold hands and feet, cold sensitivity, depression, heavy periods and prolonged periods, infertility – difficulty getting pregnant and well as a higher miscarriage rate, hair loss, thin hair, brittle nails, fluid retention.
In terms of blood work, generally TSH is high because it’s trying to tell the thyroid to produce more thyroid hormones but the thyroid hormones T3 and T4 are low or lower end of the range. You can still have under functioning thyroid EVEN if your lab test results are “normal”!
This is less common and more of a result of auto-immunity. Autoimmunity is when your body is attacking your own cells.
Over functioning thyroid symptoms:
Weight loss, increased appetite, insomnia, anxiety, tremors, heart palpitations, diarrhea, heat intolerance, sweating, fatigue, rapid heart rate, restlessness, thinning skin, enlarged thyroid / swollen neck appearance, changes in your period/ menstrual cycle .
Hyperthyroid is much less common than hypothyroid, but if you do have hyperthyroid, its much more likely due to autoimmunity (Grave`s disease).