By this point, it is well known that wine (particularly red wine) is associated with many health benefits, including a lower risk of cardiovascular disease, lower risk of obesity, and potentially increased neural function after spinal cord injury. In regards to oral health, studies have shown that alcohol consumption is a serious risk factor for oral cancer, and that heavy drinkers tend to have poorer oral health than light to moderate drinkers. Poor oral health in the case of heavy drinkers is often confounded with other factors, such as lifestyle choices involving poor dental habits and poor diets, so teasing out cause and effect in cases such as these can be difficult.

Alcohol can erode teeth due to the high acidity of some alcoholic beverages, particularly wine which tends to have a relatively low pH. However, studies regarding alcohol consumption and the number of teeth in an individual are few and far between, and those studies that do exist are quite contradictory. For example, some studies have found that alcohol consumption is linked with fewer teeth, while other studies have found the opposite, in that those that consume alcohol are less likely to lose their teeth than nondrinkers.

In regards to age, studies have found that those older individuals consuming alcohol on a regular basis is increasing. Older individuals tend to be more at risk for certain health concerns than younger individuals, particularly when it comes to the effects of alcohol consumption. As mentioned previously, many studies have found positive health effects links between wine consumption and health in humans. It may therefore by assumed that perhaps if other health concerns are being assuaged, then consuming wine may also have positive health benefits on oral health.

The study presented today examined the associations between alcohol consumption and oral health in older adults, and whether the number of teeth was associated with weekly alcohol consumption (while including the type of alcohol). Due to some limitations of this study, the results may be up for debate, and I encourage you to read the methods and results for yourself, and let us know what you think.

Methods

Participants of this study were participants in the Copenhagen City Heart Study, with consists of an adult population living in Østerbro, near central Copenhagen, Denmark. For the heart study, participants were examined four times in 27 years, and had completed a questionnaire regarding medical history, socioeconomic status, and lifestyle habits. Participants also underwent a physical examination. The oral health study presented today took place in March 2004 and August 2005 at the School of Dentistry at the University of Copenhagen. Of the possible candidates a total of 783 people participated in the oral health study, with the ages of participants ranging from 65-95 years.

Participants and those in the heart study that chose not to participate were compared in regards to lifestyle, education, and income.

Participants completed a questionnaire on lifestyle habits (including alcohol consumption, smoking, and physical activity), dental habits, how they perceive their own health, functional ability, and social relationships.

Oral examinations were performed by the same dentist, and the numbers of remaining teeth (including third molars) for each participant were counted.

Dental status for participants was expressed as the number of remaining teeth in two groups: greater than or equal to 20 (higher number of teeth), or less than 20 (low number of teeth). Covariates that were taken into account during analysis were: age, gender, education level, household income, marital status, smoking habits, leisure time, physical activity level, medication intake, saliva flow rates, self-rated health status, dental visits, diversity of social relationships, social participation, and functional ability determined using the Mobility-Tiredness Scale.

Results

Study Participants

Comparisons found that nonparticipants (both male and female) had higher proportions of individuals that were older and lower educational levels than participants.

Female nonparticipants had higher proportions of individuals with lower alcohol consumption, sedentary lifestyle, and smokers.

Male and female participants with a low number of teeth were older and tended to have lower socioeconomic statuses and unhealthy lifestyles when compared to participants with high numbers of teeth.

Participants with a low number of teeth tended to visit the dentist less than once per year, and took more than four types of medications thank participants with high numbers of teeth.

Female participants with lower numbers of teeth tended to have lower weekly alcohol intake (or no intake at all).

Male participants with lower numbers of teeth tended to report themselves as having poor/fair health than males with higher numbers of teeth.

The average number of drinks per week for heavy drinkers was 38 for males, and 22 for females.

Alcohol Consumption VS Number of Teeth

Female participants who consumed moderate amounts of alcohol had a lower chance of having fewer teeth compared to those who did not drink.

o Females who were heavy drinkers had an even lower chance of having fewer teeth.

There was no relationship between total weekly alcohol consumption and number of teeth for male participants.

Female wine drinkers who consumed more than 6 glasses per week had a lower chance of having fewer teeth than those consuming less or none at all.

There was no relationship between total weekly wine, beer, or spirit consumption and number of teeth for males, though males who consumed more than 6 beers per week had marginally significant lower chances of having fewer teeth.

Men who preferred to drink beer had a lower chance of having fewer teeth than those who did not drink.

Women who preferred to drink wine (or spirits) had a lower chance of having fewer teeth than those who did not drink.

There were no relationships found between smoking and alcohol consumption when considering weekly alcohol intake, or the type of alcohol.

Authors’ Summary

According to the authors of this study, the first important result was that women who consumed more alcohol were more likely to have greater numbers of teeth than those who did not drink. A similar trend was noted for men; however, the results were not significant. The second important result of this study was that women who drank more than 6 glasses of wine per week a lower risk of having fewer teeth than those who did not drink.

Since studies have shown that wine consumption is tightly correlated with higher socioeconomic status and healthier lifestyles, the authors attempted to control for these factors by using them as covariates in their analysis. After doing so, the results remained the same, in that women who consumed 6 glasses or more of wine per week had a lower chance of having fewer numbers of teeth than those who do not drink.

According to the authors, it’s possible that even though it has been shown that alcohol can erode teeth, the other components in the beverages (other than ethanol) may be playing a more protective role than the ethanol is damaging. For example, one study found that wine consumption was associated with lower microbial plaque deposition and lower concentrations of oral bacteria. The same study interpreted this results as indicating that some components of the wine may be preventing the adhesion of the oral bacteria on the teeth.

The last important finding, as indicated by the authors of this study, was that women who preferred to drink wine had a lower risk of having fewer teeth than women who preferred to drink beer or mixed preferences. The authors attributed this to perhaps a healthier dietary choice made by wine drinkers; however, those data were not available to determine this for certain.

Limitations and musings….

The authors of the study addressed several limitations to this study, which I feel really muddle the results found, and renders me curious whether or not these results could actually be replicated under a better designed experiment. First, out of all of the possible participants from the initial list of heart study participants, only 40% of them participated in the oral study. Since studies have shown that nonparticipation is linked to lower socioeconomic status and poorer health, there is a huge potential for selection bias (the participant pool does not represent a randomly selected pool of adults).

Another limitation is that the heart study where the participants were selected from was not designed for this type of oral study. There was no information regarding past dental history, since that was not the intent of the heart study, and therefore there was no way of knowing when the tooth loss occurred in individual participants or their dental habits.

In regards to strengths, the authors site a large sample size, and the wealth of information that allowed them to control for many covariates, however, in my opinion, I do not think this justifies choosing from a pool of individuals where no dental health history is known. If you’re going to perform an oral health study, shouldn’t one have an understanding of the dental history of the participants? All of these limitations mean that the results of the study may only apply to the specific pool of individual participants in the study, and may not be generalized to other groups or the older adult population as a whole.

Overall, I didn’t agree with the methods employed for choosing study participants, and would like to see a study performed where participants are specifically chosen for this type of study, and not simply picked from a pool already available from an unrelated study.

What do you all think about this? What improvements on the study would you like to see performed? Please feel free to leave your comments below by clicking on the “comment” link at the end of this post.

Source: Heegaard, K., Avlund, K., Holm-Pedersen, P., Hvidtfeldt, U.A., Bardow, A., and Grønbæk, M. 2011. Amount and type of alcohol consumption and missing teeth among community-dwelling older adults: findings from the Copenhagen Oral Health Senior study. Journal of Public Health Dentistry 71: 318-326.

DOI: 10.1111/j.1752-7325.2011.00276.x

I am not a health professional, nor do I pretend to be. Please consult your doctor before altering your alcohol consumption habits. Do not consume alcohol if you are under the age of 21. Do not drink and drive. Enjoy responsibly!