Nestled in the tissues of your neck is a small unassuming organ that wields enormous power over your body. It's called the thyroid. Like the operations manager in a company, its role is to make sure that the cells in your body are working properly. It does that by using hormones to deliver messages to every single one of them. This high-ranking organ is made up of lobules that each contains smaller cells called follicles, which store the hormones the thyroid sends out into your blood. Two of the most important hormones it produces are thyroxine and triiodothyronine, or T3 and T4. As messengers, the hormone's job is to instruct every cell in the body when to consume oxygen and nutrients. That maintains the body's metabolism, the series of reactions our cells perform to provide us with energy. This hormonal notification from the thyroid gets the heart pumping more efficiently, and makes our cells break down nutrients faster. When you need more energy, the thyroid helps by sending out hormones to increase metabolism. Ultimately, the thyroid allows our cells to use energy, grow and reproduce. The thyroid is controlled by the pituitary gland, a hormonal gland deep in the brain that oversees the thyroid's tasks, making sure it knows when to send out its messengers. The pituitary's role is to sense if hormone levels in the blood are too low or too high, in which case it sends out instructions in the form of the thyroid- stimulating hormone. Even in this tightly controlled system, however, management sometimes slips up. Certain diseases, growths in the thryoid or chemical imbalances in the body can confuse the organ and make it deaf to the pituitary's guiding commands. The first problem this causes is hyperthyroidism, which happens when the organ sends out too many hormones. That means the cells are overloaded with instructions to consume nutrients and oxygen. They become overactive as a result, meaning a person with hyperthyroidism experiences a higher metabolism signaled by a faster heartbeat, constant hunger, and rapid weight loss. They also feel hot, sweaty, anxious, and find it difficult to sleep. The opposite problem is hypothyroidism, which happens when the thyroid sends out too few hormones, meaning the body's cells don't have as many messengers to guide them. In response, cells grow listless and metabolism slows. People with hypothyroidism see symptoms in weight gain, sluggishness, sensitivity to cold, swollen joints and feeling low. Luckily, there are medical treatments that can help trigger the thyroid's activities again, and bring the body back to a steady metabolic rate. For such a little organ, the thyroid wields an awful lot of power. But a healthy thyroid manages our cells so effectively that it can keep us running smoothly without us even noticing it's there.
U tkivu vašeg vrata smešten je mali, skroman organ koji ima ogromnu moć nad vašim telom. Njegovo ime je štitna žlezda. Poput rukovodioca posla u kompaniji, njena uloga je da se postara da ćelije u vašem telu funkcionišu. Ona to radi uz pomoć hormona, kojima nosi poruke do svake ćelije. Ovaj bitni organ sastoji se od lobula, koje sadrže manje ćelije zvane folikulima, koji skladište hormone koje štitna žlezda šalje u vaš krvotok. Najbitnija dva hormona koja ona proizvodi su tiroksin i trijodotironin, tj. T3 i T4. Posao hormona kao glasnika je da naloži svakoj ćeliji u telu kada da uzima kiseonik i hranljive materije. Ovo održava metabolizam tela, niz reakcija koje obavljaju naše ćelije kako bi nas snabdevale energijom. Ova hormonska obavest od štitne žlezde tera srce da efikasnije pumpa a naše ćelije brže razgrađuju hranljive sastojke. Kada vam je potrebno više energije, štitna žlezda pomaže tako što šalje hormone da se pojača metabolizam. Na kraju, štitna žlezda našim ćelijama dozvoljava da koriste energiju, rastu i razmnožavaju se. Štitnu žlezdu kontroliše hipofiza, hormonska žlezda u dubini mozga koja nadgleda zadatke štitne žlezde i stara se da ona zna kada da pošalje svoje glasnike. Uloga hipofize je da oseti kada su nivoi hormona u krvi preniski ili previsoki, u kom slučaju šalje uputstva u obliku hormona koji stimuliše štitnu žlezdu. Ipak, čak i u ovom strogo kontrolisanom sistemu, upravi se ponekad omakne. Određene bolesti, izrasline u štitnoj žlezdi ili hemijska neravnoteža u telu mogu da zbune ovaj organ čime on ogluvi na uputstva hipofize. Prvi problem koji iz ovoga proizilazi je hipertireoza, koja nastaje kada organ šalje previše hormona. To znači da su ćelije preopterećene uputstvima da konzumiraju hranljive materije i kiseonik. Za posledicu postaju preaktivne, što znači da osoba sa hipertireozom doživljava veći metabolizam u obliku bržeg rada srca, stalne gladi i munjevitog gubitka težine. Tim osobama je i vruće, znoje se, anksiozne su i imaju poteškoće sa spavanjem. Suprotan problem je hipotireoza, koja nastaje kada štitna žlezda šalje premalo hormona, što znači da ćelije u telu nemaju dovoljno glasnika da ih vode. Kao posledica, ćelije rastu trome i metabolizam se usporava. Osobe sa hipotireozom doživljavaju simptome poput viška kilograma, usporenosti, osetljivosti na hladnoću, nateklih zglobova i osećaja depresije. Srećom, postoje lekovi koji mogu pomoći da se ponovo aktiviraju aktivnosti štitne žlezde i da se telo vrati na stabilnu brzinu metabolizma. Za tako mali organ, štitna žlezda ima ogromnu moć. Ali zdrava štitna žlezda upravlja našim telom tako efikasno