BALTIMORE — Ann De Lacy took voice lessons in college, sang in her church choir and could easily, unlike most Americans, belt out the national anthem. But these days you won't find her singing so much as "Jingle Bells" to her grandkids.

The problem isn't her hobby but her former job: De Lacy was a classroom teacher for 33 years, and the constant talking has made her perpetually hoarse.

"Now I can barely talk. It puts so much stress on the voice," said De Lacy, now president of the Howard County Education Association. "You can't not talk when you're a teacher. And it's like we're actresses and actors — the voice is everything."

The showbiz analogy is apt. Teachers, like professional singers, are vulnerable to severe voice problems, according to a Johns Hopkins throat specialist. Dr. Lee M. Akst, an assistant professor at the Johns Hopkins School of Medicine and director of the Johns Hopkins Voice Center, urges teachers to take voice stress seriously.

"Teachers are a particularly high-risk profession, even more than salespeople or doctors or lawyers," said Akst.

Nearly 58 percent of teachers report voice difficulties some time in their professional lives, twice the incidence of the general population, Akst said. As many as 47 percent of American teachers experience voice problems on any given day, and one in 10 teachers has been forced out of the profession because of them, according to the American Academy of Otolaryngology-Head and Neck Surgery.

Because teachers need to use their voices, often in loud environments for long periods of time, their vocal cords can be damaged. The louder people speak, the more violently their vocal cords collide against each other. Just as dancers and runners get calluses and blisters on their feet, people who talk a lot, and talk loudly, can develop nodules and polyps on their vocal cords. These sometimes go away on their own, but it's hard for teachers to get the rest necessary to make that happen.

"If you're in a classroom of two dozen 8-year-olds, you have little choice but to try to push through," Akst said. "That takes a bad voice and makes it worse."

While not dangerous to personal health, the nodules and polyps can make speech permanently hoarse and painful. Having an inflamed throat may also make it harder to tolerate the colds and flu that are already a professional hazard for anyone working around kids, he said.

"I typically lose my voice once a year, to the point where it's completely gone," said Erika Herman, a third-grade teacher at Hillcrest Elementary School in Catonsville, Md. "Last year I went to the doctor, and she said, basically, just rest."

That's something Herman finds hard to do given "the amount of talking we do through the day, if you're outside at recess or the cafeteria and you have to raise your voice."

Herman said there are days when she tells her class that she's using her "whisper voice."

"I don't know how that would fly with middle school and high school kids," she said. "Elementary school kids fall into place and feel sorry for you."

One of her teaching colleagues recently spent an entire weekend without talking to get an ailing voice back in shape for the next school week.

Joy Appel Brown, who works with small groups of children as a math resource teacher at Hillcrest and Pot Spring Elementary in Timonium, Md., said the problem was much worse during the 20 years she was a classroom teacher.

"When I was younger and in the classroom, where I used my voice 'round the clock, I developed a nodule on my throat and was told by an ear, nose and throat doctor it was from overuse," she said. The doctor prescribed rest and, since the school year was almost over, Brown was able to comply. The problem went away over the summer but resurfaced when school was back in session.

She had bouts of laryngitis throughout every school year after that. The problem has improved since she has shifted out of the classroom, but her throat remains "prone to issues."

"I'm vulnerable, but it's much better," she said. "I know that I would be having lots more issues if I was still teaching full time."

There are things that can be done to help an ailing voice. Keeping the vocal cords hydrated helps, so Akst suggests drinking lots of water and limiting diuretics such as caffeinated beverages and alcohol. Staying hydrated is especially important for someone taking medications with drying side effects, such as antihistamines, decongestants and antidepressants.

Acid reflux can contribute to the problem of raw vocal cords, even in people who do not experience symptoms such as heartburn, Akst said. He recommends limiting acidic foods like tomato sauce and citrus as well as fatty dishes, which contribute to reflux because they take longer to digest.

Smoking also exacerbates voice issues, so quitting can help.

Akst suggests that anyone experiencing voice problems for more than two or three weeks see a doctor. Surgery is an option to remove to remove scars that limit voice quality. Patients sometimes work with a therapist to learn methods of modulating the voice and breathing strategies — from the diaphragm, just like singers are taught — to lessen the strain.

Amplification systems in schools, like the one installed in Nantucket Elementary School in Crofton, Md., when it opened three years ago, also can help. Teachers there wear cordless microphones around their necks. The system helps kids at the back of the classroom hear better and saves the teacher's voice.

"This is a powerful, powerful tool," said Nantucket principal Diana Strohecker, recalling how weary her own voice was when she was a classroom teacher. "There were days where I would literally go home and, really, I couldn't talk."

Teaching strategies that have students doing more of the talking are another solution. In seminars she holds for teachers, Patricia C. Baltzley, acting director of science, technology, engineering and math in Baltimore County, Md., encourages them to use "cooperative learning" strategies, which combine traditional classroom lectures with group and individual activities. The idea is to get students more involved and engaged, but there's also an upside for the teacher's voice.

"The mantra is, we want to move teachers away from being 'the sage on the stage to the guide on the side,'" Baltzley said. "If they're up on the stage, it is just like an opera singer. They're on all the time."

Tips for keeping the teacher's voice healthy

— Limit vocal overuse as much as possible.

— Keep hydrated, particularly if antihistamines, decongestants, antidepressants and other medications with drying side-effects are being taken.

— Reduce acid reflux by limiting foods containing caffeine, carbonation, alcohol, tomato and citrus.

— Don't smoke.

— Use an amplification system if possible.

— Find opportunities to rest your voice during the day if possible (interspersing lecture-style teaching, for example, with independent work periods for students).

— Speak with good breath support and vocal technique to minimize strain on vocal cords.

— Dr. Lee Akst

Distributed by McClatchy-Tribune Information Services