Brushing your teeth does not directly cure or prevent the common cold, as the infection is caused by a virus in the respiratory system. However, maintaining oral hygiene is important for overall health while sick. Continuing to brush twice daily protects your mouth from secondary issues that commonly arise during a viral illness. This habit helps manage cold symptoms while safeguarding dental health from related side effects.
Understanding Cold Transmission
The common cold is a viral illness, most frequently caused by rhinoviruses, which primarily target the upper respiratory tract. The infection is transmitted when respiratory droplets containing the virus enter the body through the nose, mouth, or eyes. These droplets are aerosolized when an infected person coughs, sneezes, or talks. Since the cold is a systemic infection of the respiratory system, a toothbrush cannot reach the site of the viral infection itself.
Oral hygiene, including brushing and flossing, is designed to disrupt and remove bacterial plaque from the teeth and gums. Plaque is a biofilm composed of bacteria that, if left undisturbed, can lead to localized problems like gingivitis and dental decay. The mechanism of removing this bacterial buildup is entirely separate from clearing a viral infection from the nasal passages and throat. Brushing manages bacterial ecology and has no direct effect on the progression or duration of the cold virus.
Maintaining Oral Health During Illness
When sick, the oral environment faces specific challenges that make continued brushing important. Nasal congestion often forces mouth breathing, which rapidly dries out oral tissues. This reduces the protective flow of saliva, which washes away food debris and neutralizes cavity-causing acids. A lack of saliva creates an ideal environment for harmful bacteria to multiply, significantly increasing the risk of developing cavities and gum disease.
Many common cold and flu remedies contain ingredients that threaten tooth enamel. Cough syrups and throat lozenges are often loaded with sugars, which feed acid-producing bacteria in the mouth. Acidic cold beverages or stomach acid from vomiting can also erode enamel. If vomiting occurs, rinse the mouth immediately with water or a baking soda solution to neutralize the acid. Wait about 30 minutes before brushing to allow the enamel to re-harden.
Continuing your regular brushing routine helps mitigate the negative effects of dry mouth and remedy ingredients. A clean mouth also offers a feeling of comfort and freshness when dealing with congestion and sickness. Maintaining this simple habit prevents short-term illness from leading to long-term dental problems.
Viral Contamination and Toothbrush Care
A toothbrush can act as a fomite, an object capable of harboring infectious agents. However, the risk of self-reinfection with the same common cold virus is low because the body develops antibodies against that specific strain. Viruses and bacteria can survive on toothbrush bristles for a limited period, with some bacteria persisting longer than the cold virus itself.
The primary concern regarding contamination is the risk of transmitting pathogens to other people or introducing a secondary bacterial infection. If toothbrushes are stored in the same holder, bristles can touch, allowing for cross-contamination between family members. Viruses and bacteria, including those that cause strep throat, can transfer this way.
To minimize these risks, replace the toothbrush or brush head shortly after recovery from the cold. This prevents reintroducing opportunistic bacteria or spreading the illness to others in the household. Storing the toothbrush upright and allowing it to air-dry between uses discourages microbial growth. Toothbrushes should always be stored apart to prevent contact between the bristles.