For such a tiny organ that looks a lot like a butterfly, the thyroid gets a lot of attention. But it makes sense when you consider just how vital its task is: this gland helps to control the body's metabolism. If you're stuck trying to grasp why that's important and what exactly metabolism is, check out this helpful video, and read more about the thyroid's role here and here.

The tools your thyroid uses to get the job done are triiodothyronine (T3) (that's a tricky word: learn how to say it!) and thyroxine (T4), the two hormones that act as messengers to all your body's cells. Fun fact: your thyroid needs an element called iodine to make these hormones, an ingredient your body can't make and which it has to get from the food you eat, instead. If you want to know more about how T3 and T4 are made, take a look at the thyroid cells they come from.

Since it works 24/7, it may seem like the thyroid is the boss in this situation. But really, that position belongs to the pituitary. If you see where this tiny gland lives, it's quite easy to understand how it wields such power: it commands hormonal function from the power-seat of your brain! Learn all about the pituitary, and why it is known as the 'master gland'. (Hint: thyroid hormones aren't the only ones it controls.)

But when the all-powerful pituitary fails, your body really feels it, in the shape of hyperthyroidism and hypothyroidism. Want to learn more about the symptoms that these conditions bring with them? Think hyperactivity, mood swings, trouble sleeping, and unexpected weight loss, versus tiredness, feeling cold, sadness, and weight gain. You can find out here whether you're at risk of developing these conditions here, and here. Learn more about thyroid cancer here.

Keep up to date on thyroid news and research with the American Thyroid Association and the British Thyroid Foundation—and even when you're not learning about this important gland, remember that it will keep on doing its job in the background.

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