Updated May 17, 2015.
Our voice is as personal as our signature: no two voices are exactly alike, and they represent how we are heard in the world. As we age, changes in the tissues which produce our voices - along with some lifestyle habits - can modify how we sound. Here's a look at why our voices may shift as we get older.
How the voice is produced:Â Sound in the larynx or "voice box" is created thanks to two bands of smooth muscle called the vocal folds, or vocal cords, lying at the opening of the trachea or windpipe.
 The vocal cords are positioned side by side like sliding doors; when we are quiet, they stay open so we can breathe. When we speak, the doors snap shut, and as air is expelled by the lungs, vibrations between the folds create the sound we know as voice. The folds also close during coughing and swallowing.
Movements in the muscles of the throat and mouth - including the jaw, lips and tongue - create the particular sounds associated with speech. All of the structures in the larynx, including connective tissue and muscles muscles - along with the resonating open chambers within the skull - affect the tone and pitch of each unique voice.
Why voices change as we get older: Just as other parts of the body undergo physiological changes with age, so do the structures which produce our voice. Vocal cords or folds are comprised of three layers: a muscular inner layer, a collagen layer and a thinner vibrating layer.
According to a 2011 review published in Otolaryngology: Head and Neck Surgery, the same way skin becomes thinner and less elastic with age, so do the vocal folds.
 Changes in the anatomy of the larynx - such as its position within the neck and stiffening of its cartilage, in addition to the oral cavity increasing in both volume and length - affect how sounds resonate within these structures. Muscles within the neck and throat may become weaker and more easily tired, which may affect both vocal volume and quality.
Other age-related changes such as less lung capacity can affect how loudly an older person speaks; even differences in posture can affect the voice if lung capacity is diminished.Â
Beyond so-called normal aging, certain diseases or conditions can impair voice production. These include stroke and Parkinson's disease, which may affect how well the central nervous system triggers and controls speech.Â
Symptoms of an aging voice: Because of these normal aging changes in the larynx, a number of changes may be heard over time:
- Instability in pitch
- Breathiness
- Hoarseness
- Changes in pitch or decreased range
- Diminished projection (weak voice)
Otolaryngologist and Director of the Johns Hopkins Voice Center Lee Akst notes these voice problems can erode the quality of life of older people who stop socializing or interacting with others because it takes too much effort to be heard.
In fact, a small 2004 longitudinal study published in the Journal of Voice found that older male subjects who were self-conscious about their hoarse or quiet voices tended to avoid social situations.
"Patients say to me, 'I sound rougher, people can't hear me, I can't get loud," Akst explains. "We don't really know how many people are walking around with these kinds of voice problems; many may accept it as an unavoidable side effect of aging and never seek help."
How can I sound younger? Solutions for voice problems:  Akst says that we have little recourse against physiological changes; that is, you can't turn back the biological clock on behalf of your vocal cords. Good vocal hygiene, such as staying well-hydrated and not yelling or screaming is a must. In addition, interventions like speech therapy can be an effective treatment to help patients with voice issues learn to vocalize more efficiently and effectively with less fatigue or strain.
"In a functional way, we can learn to compensate for age-related structural changes," he oberves. "Voice therapy can help strengthen a voice by building back breath support, diminishing strain as you produce your voice, and helping to coordinate the muscles of all the structures - lips, tongue, palate, pharynx - to make the sound."
Akst notes that most patients improve with voice therapy alone. While they may not sound like they did when they were 40, voice therapy helps promote a stronger voice. For those still struggling to be heard, a procedure called vocal cord augmentation involves injecting a synthetic filler into the deepest muscle layer of the vocal folds. This more invasive therapy can last from just a few months, to a permanent change in the case of a surgical implant.
"It's an uncomfortable procedure, with a risk of side effects like bleeding," says Akst. "It works best in conjunction with voice therapy, and if you were to choose only one course of treatment, you'd do better with just voice therapy. But for patients with incomplete glottal closure (ie. the vocal folds don't vibrate tightly together), this can help them sound louder with an improved voice."
Sources:
Alice Goodman. Management of the Aging Voice. ENT Today March 2008.
http://www.enttoday.org/details/article/517115/Management_of_the_Aging_Voice.html
Martins RH, Gonçalvez TM, Pessin AB, Branco A. "Aging Voice: Presbyphonia." Aging Clin Exp Res. 2014 Feb;26(1):1-5.
Michael M Johns. Lindsey Clemson Arviso, and Fadi Ramadan. "Challenges and Opportunities in the Management of the Aging Voice." Otolaryngology: Head and Neck Surgery 2011 vol:145 iss:1 pg:1 -6
Taking Care of Your Voice. US National Institute on Deafness and Other Communication Disorders (NIDCD) Public Information Sheet. Accessed June 5, 2014.
https://www.nidcd.nih.gov/health/voice/pages/takingcare.aspx
Tips for Healthy Voices. American Academy of Otolaryngology-Head and Neck Surgery Public Information Sheet. Accessed June 5, 2014.
http://www.entnet.org/?q=node/1441
Verdonck-de Leeuw IM, Mahieu HF. Vocal Aging and The Impact on Daily Life: a Longitudinal Study. J Voice 2004; 18:193–202.
Voice Disorders: The Geriatric Voice. Johns Hopkins Voice Center Public Information Sheet. Accessed June 6, 2014.
http://www.gbmc.org/body.cfm?id=1564
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