We now know that our diet shapes the composition of our microbiota and, therefore, our health. While many studies have shown good eating habits to have a positive influence on the composition of the gut microbiota, few have explored the relationship between eating habits and salivary microbiota. Since food enters the body via the mouth, does the composition of the salivary microbiota reflect our eating habits and, accordingly, our health status?
Teenagers’ eating behavior under the microscope
To find out, the authors analyzed the salivary microbiota of 842 healthy Finnish teenagers. The teenagers completed a questionnaire aimed at determining their eating habits and were classified according to whether they avoided fruits and vegetables (no FV diet) (42.9%), had healthy meals (45.5%) or junk food (11.6%) and regularly had breakfast (83.1%) and dinner (82.4%).
Show me your salivary microbiota and I will tell you how you eat
Surprisingly, the teenagers’ salivary microbiota remained similar both in terms of diversity and composition whatever their food preferences (no FV diet, healthy meals, or junk food). On the contrary, the regularity of meals did influence diversity. Teenagers with a regular diet had greater microbial diversity than those who skipped meals. Consequently, “irregular eaters” are likely to show reduced diversity, with a diverse microbiota generally considered beneficial to health.
Increase in bacterial content associated with poor eating habits?
The study also showed an abundance of certain bacteria in the saliva of teenagers with a no FV diet and of those skipping meals. The presence of these bacteria in the saliva has previously been associated with oral disease and poor oral hygiene. The authors believe that meal regularity is more important to the composition of the salivary microbiota than diet, and that some salivary bacteria may serve as an indicator of poor eating habits.
