Many of us rely on our voices as our primary form of communication. From high or soft lilting tones to low-booming ones, our voices come to identify us like audible fingerprints. And our voices can change throughout our lives and in times of illness, injury, and misuse. Our voices' quality and pitch may alter, or we may experience difficulty or even pain when we speak. And people who use their voice for a living - teachers, singers, actors, salespeople, telemarketers - may go through more episodes of voice troubles.

The most common voice change occurs during puberty, when our voice box (or larynx) grows right along with the rest of our body. On average, a boy's larynx will grow more than a girl's - developing into the Adam's apple more common in males. And with the larger size come thicker, longer vocal cords and a deeper voice. As the voice box adjusts to its new size, voices crack and falter, eventually evening out to a more "adult" tone.

Our voices may change as we get older, too. The muscles in our throat may lose some of their mass, tone, and coordination. We may also have less mucus to lubricate the vocal cords.

Many people experience voice changes during upper respiratory infections and colds. Infections and viruses can cause vocal cords to swell and lead to the raspy, hoarse, breathy, or rough voice of acute laryngitis. Laryngitis usually resolves on its own after a period of voice rest and drinking plenty of water. If voice changes persist for longer than 2 to 4 weeks, seek the advice of your doctor or an otolaryngologist (an ear, nose, and throat (ENT) doctor). A voice change that lasts longer than one month in a smoker may indicate throat cancer.

Smoking damages the larynx and triggers voice changes, most notably hoarseness. And smoking causes most cases of throat cancer, also called laryngeal cancer. Smokers who also drink alcohol seem to have even higher risk. Along with persistent or worsening hoarseness, other symptoms of throat cancer include pain or difficulty swallowing, difficulty breathing, sore throat, pain in ear, and lump in the neck.

Another common irritant is stomach acid. If acid finds its way back up to the larynx, it can cause irritation and laryngitis-type voice changes. The persistent acid of gastroesophageal reflux disease (GERD) can cause quick spasms of the vocal cords that make it hard to talk or breathe. Treat the acid first, and the voice changes should resolve as well.

Our voice may change when we misuse, overuse, or abuse it. Think of that raspy, sore feeling you have after shouting at a loud concert or football game. Singers and those who speak for a living may develop lesions on their vocal cords. Nodules, polyps, and cysts are like calluses on the vocal cords that can change the quality of the voice. These are benign and most are treatable with rest, voice therapy, or surgery.

Certain types of medication can change the voice. Some medications dry out the vocal cords. Others that thin the blood may lead to easier bruising of the vocal cords. Medications that cause fluid retention may cause the vocal cords to swell, and those that trigger coughing or throat clearing can irritate and damage. Speak to your doctor or pharmacist to find out if any of your medications may be causing voice changes.

Some causes of voice changes may be well beyond our control. For instance, the vocal cords may become paralyzed due to infection, tumours, a surgical injury, or the cause may be neurological. And muscle spasms can cause stiffening of the vocal cords, difficulty getting words out, and a voice that sounds strangled or strained, a disorder called spasmodic dysphonia.

But you can take control of caring for your voice and protecting it from damage:

Keep vocal cords moist. Your vocal cords need lubrication to function smoothly, so drink plenty of water. Drink less alcohol and caffeine, both diuretics that cause the body to lose water and lead to dehydration and dry vocal cords. Add moisture to the air around you using a humidifier, and moisture to your mouth and throat by sucking on lozenges or chewing gum. Eat foods rich in mucus-stimulating vitamins A, C, and E.

Avoid irritants. Smoke is probably the voice's worst enemy. It irritates the throat and increases the risk of throat cancer. So if you smoke, quit. Secondhand smoke can do damage, too. Alcohol is another vocal cord irritant, so minimize your intake and watch out for alcohol in mouthwash. Avoid spicy foods that trigger stomach acid.

Be kind to your voice. Speak in your natural pitch and tone as often as possible. You put undue strain on your vocal cords when you yell, scream, or talk loudly. And surprising as it may be, whispering can be just as damaging as shouting. Avoid throat clearing, which is very rough on the vocal cords. Switch to non-vocal, visual cues when you need to give your voice a rest. Also, try speaking from your diaphragm rather than from your throat.

Give your voice a boost. Support your voice by filling up your lungs before you speak. Make use of microphones and vocal amplification when speaking to a large audience. And if you will be singing or speaking at length, give your voice a warm-up first. Do "trills" with your tongue or lips or vocalize vowel sounds, gliding from low to higher tones.

Listen to your own voice. Your voice will let you know when something is wrong. Seek medical attention if you experience the following:

  • sudden voice loss after yelling, which may indicate a vocal cord hemorrhage
  • spitting up blood or noticing blood in the mucus
  • hoarseness that lasts longer than 3 weeks
  • hoarseness not accompanied by a cold or flu
  • difficulty swallowing
  • feel a lump in your neck
  • pain when speaking or swallowing
  • difficulty breathing