The thyroid gland is about two inches long and about one inch wide. It sits at the base of the neck, straddling the windpipe. It weighs about an ounce. When your healthcare provider encircles your neck with her hands and asks you to swallow, she is checking the size of your thyroid.
The thyroid’s main job is to control metabolism by secreting hormones. If you, an adult, have too much thyroid hormone (hyperthyroidism) you will lose weight. If you have too little (hypothyroidism), you will gain weight. But that’s not all. Thyroid hormones have a strong influence on the nervous system, which influences everything. In turn, a change in the nervous system affects the thyroid. Together, the thyroid and the pituitary in your brain function like the heating/cooling system in your home. For example, if the temperature in your home falls below a preset minimum on your thermostat, the furnace will start and send heat around your house until the preset temperature is reached. Then, once again responding to the temperature on the thermostat, the furnace will stop sending heat. What does all this mean for the way you feel and behave?
If your thyroid gland isn’t functioning properly it will not respond to the pituitary. The level of thyroid hormone in your blood stream will remain the same or drop further. You may feel tired or not mentally sharp. If this persists, you may feel depressed or moody. You may have difficulty sleeping, in spite of feeling tired and sleepy. Physically, you may begin gaining weight, no matter how little you eat or how much you exercise. Meanwhile, your pituitary is frantically sending out thyroid stimulating hormone (TSH). If this goes on long enough – the pituitary in overdrive – it may result in enlargement of the pituitary. But most people never reach this stage. They generally feel sick enough to consult a healthcare provider.
On the other hand, if your thyroid keeps sending out thyroid hormone no matter how little TSH there is in your blood, your symptoms will be different. Emotionally you may feel anxious for no reason or more anxious for the reasons you do have. There’s some evidence that prolonged stress increases your risk for hyperthyroidism. You may be irritable or have difficulty concentrating. You may have difficulty sleeping, just as with low thyroid. Physically you will begin to lose weight, no matter how many carbs you pile on. You might notice your heart racing, often greater than 100 beats per minute. Your hands may tremble. Eventually your thyroid will enlarge and you will feel or see the enlargement at the base of your neck. But, once again, most people have consulted a healthcare provider before this occurs.
Bottom line? That little gland in your neck is powerful. It can cause both physical and emotional/mental symptoms. The mind and the body are connected. They are both part of us. It may be only one that is causing your symptoms. But always suspect both, not just one, when you aren’t feeling well.