The vocal cords are responsible for producing sound in the voice. They are located in the larynx—a part of the respiratory system that allows air to flow from the throat to the lungs. When air is expelled from the lungs and passes through the larynx, it causes the vocal cords to vibrate, creating sound.
Changes in Voice
The muscles that allow the vocal cords to move begin to wear down (just like other muscles) as we age. (Photo: Shutterstock).
The vocal cords consist of three main parts: the vocal muscle, the vocal ligament, and the mucous membrane (which contains glands) that covers them.
Before puberty, the sound produced by the vocal cords does not vary much. However, during puberty, hormones begin to take effect. This alters the structure of the larynx, making the “laryngeal prominence” in males more pronounced. After puberty, the length of the vocal cords is about 16 mm in males and 10 mm in females.
Women’s vocal cords shorten and thin by 20-30% after puberty. This is why women often have higher-pitched voices than men.
Even after puberty, hormones can affect the voice. For instance, a woman’s voice may vary depending on the stage of her menstrual cycle. The best vocal quality is typically during ovulation, as the glands produce more mucous, enhancing the vocal cords’ functionality.
Research also indicates that women on birth control pills experience less change in vocal quality. Conversely, hormonal changes during the premenstrual phase can stiffen the larynx, making it less flexible.
Age-Related Changes
As we age, the larynx begins to increase in mineral content, becoming harder and more bone-like rather than cartilaginous. This change can start in the 30s, particularly in males, making the larynx less flexible.
Changes in the larynx can begin to occur from the age of 30. (Photo: Shutterstock).
The muscles that allow the vocal cords to move also begin to wear down (like other muscles) as we age. The ligaments and supporting tissues of the vocal cords lose elasticity, becoming less flexible.
In addition, lung function declines, reducing the force of air expelled from the lungs to produce sound. The number of glands producing protective mucous also decreases, along with the ability to control the larynx.
Lifestyle Factors
Lifestyle factors can increase the risk of vocal cord damage. These can alter your voice.
For example, smoking causes localized inflammation, increases mucous production, but can also dry out the mucous membranes. Alcohol has a similar effect. Over time, these factors can damage the vocal cords, changing the tone of the voice.
Some prescription and over-the-counter medications can also alter the voice, such as steroid inhalers used for laryngitis. Blood thinners can also harm the vocal cords, resulting in a hoarser voice.
Smoking causes localized inflammation, increasing mucous production. (Photo: Shutterstock).
Another lifestyle factor could be vocal abuse, commonly seen in singers and those who rely on their voices for work, such as teachers and fitness trainers.
This can lead to a rare condition known as “Reinke’s edema”, which causes fluid to swell in the vocal cords, altering the pitch of the voice.
In cases of “Reinke’s edema” that are severe, patients may need to undergo surgery to drain the fluid. In most cases, rest, hydration, and avoiding irritants (such as tobacco and alcohol) are necessary. Speech therapy can also help address changes in sound.
