Influence of drinking coffee on halitosis
Kinya Higuchi1*, Shunichi Honda2,3, Takao Tsuji3
1) Higuchi Dental Clinic, 2)Honda Dental Co., 3)Department of the Microbiology, Fujita Health University School of Medicine
It is well known that garlic, onion and alcohol induce halitosis. Many halitosis patients also complain that they sense oral malodor after drinking coffee. Coffee may lead to reduced salivary flow and to increased bacteria. On the other hand, a report stated coffee reduced volatile sulfur compounds (VSCs) levels using a decarboxylase incubation assay (in vitro). However there was no report of the influence of drinking coffee on halitosis in the human body. We studied the sequential change of drinking coffee and found some significant effect.
10 healthy adults (male 5, female 5, age 20-35) participated in this study. They were randomly separated into two groups (crossover study). Half of them drank coffee (140ml) and then measured the strength of halitosis. On a different day, this group consumed water (140ml) and measured again. The other group drank water first and measured. And on a different day, consumed coffee, and measured again. Measurements were repeated 4 times; before drinking coffee or water, 15 minutes after drinking, 1 hour and 2 hours afterwards. Malodors from intraoral gas and exhalation were investigated. The strength of oral malodor was evaluated by organoleptic tests and breath gas monitors (BB Checker and Oral Chroma). Statistically analyses were performed with the Man Whitney U-test.
Organoleptic tests of intraoral air showed higher levels of malodor strength at one hour and two hours after drinking coffee than after drinking water (Fig.1). Similar change was observed in intraoral air by measuring with one of the breath gas monitor, BB checker at two hours after drinking (Fig.4). Reverse change was observed in intraoral air and exhalation by measurements with another gas monitor (Fig.6, 7, 9, 10, 11), Oral Chroma. Drinking coffee resulted in lower VSCs levels of intraoral air and exhalation more than drinking water.
Coffee may have various contradictory effects on oral malodor. Coffee has inherent smell and low salivary pH. Caffeine also leads to reduce salivary flow. Reductions of salivary pH and flow which were thought to bring bad oral conditions caused anxious sense about bad breath to the patients. These natures were thought to cause halitosis and disorders of oral physiological function. Conversely, some components of coffee, caffeine, chlorogenic acid and protocatechuic acid were reported to have antibacterial ability, and as a result, it suppressed the oral malodor. These results were suggested that other gases were associated with ill effect of coffee drinking.
It can be concluded through our study that coffee reduced VSCs. But on the other hand, coffee made halitosis worse by producing certain gases other than VSCs. More studies are needed to clarify the mechanism of influence of coffee on halitosis.
Gov Y, Sterer N et al: In vitro effect of coffee on oral malodor-related parameters. J. Breath Res. 4: 1-5, 2010.
Lee PPC, Mak WY et al: The aetiology and treatment of oral halitosis: an update. Hong Kong Med. J. 10: 414–8, 2004.