The mouth represents a rich microbiome that is easily accessible. Over the past ten years, it has become clear that defining a "healthy"
microbiome is a critical step in discovering how variations in the
bacteria found in and on our body contribute to both disease and
While scientists now know a great deal about what bacteria
live in our mouth and throughout the body, it is still unclear whether
differences in the human microbiome that are seen in many disease states
are a symptom of the disease or part of the underlying cause.
‘Metabolic diseases lead to increases in salivary glucose; alterations of the bacteria found in the mouth; and increased risk of cavities and gum disease.’
A team of scientists from The Forsyth Institute and the Dasman
Diabetes Institute in Kuwait have found that metabolic diseases, which
are characterized by high blood pressure, high blood sugar, and obesity - leads to changes in oral bacteria and puts people with the disease at
a greater risk for poor oral health.
This study of more than 8,000 ten
year olds in Kuwait showed that metabolic diseases lead to increases in
salivary glucose; alterations of the bacteria found in the mouth; and
increased risk of cavities and gum disease. This work reinforces the
need for preventive dental care and greater integration between medical
and dental care.
The study, titled, "The Salivary Microbiome is altered in the Presence of High Salivary Glucose," can be found on PLOS ONE
Dr. Max Goodson, the study's lead author, said, "Our research is
providing further evidence of the connections between the mouth and some
of society's most costly and deadly systemic diseases - and of the
importance of using the mouth as a tool for preventive health."
Summary of Study
We measured the glucose concentration, bacterial counts, and
relative frequencies of 42 bacterial species in whole saliva samples
from 8,173 Kuwaiti adolescents (mean age 10.00 ą 0.67 years) using DNA
probe analysis. In addition, clinical data related to obesity, dental
caries, and gingivitis were collected. Data were compared between
adolescents with high salivary glucose (HSG); glucose
concentration and those with low salivary glucose.
that HSG was associated with dental caries and gingivitis in the study
population. The overall salivary bacterial load in saliva decreased with
increasing salivary glucose concentration. Under HSG conditions, the
bacterial count for 35 (83%) of 42 species was significantly reduced,
and relative bacterial frequencies in 27 species (64%) were altered, as
compared with LSG conditions.
These alterations were stronger predictors
of high salivary glucose than measures of oral disease, obesity, sleep
or fitness. These observations clearly indicate that metabolic diseases,
such as diabetes, that produce elevated glucose in blood and saliva can
significantly alter the oral microflora.
Samples were obtain through the Forsyth Kuwait Healthy Life Study,
is a longitudinal cohort investigation of more than 8,000 children.
Forsyth has worked with The Dasman Diabetes Institute and the
Kuwait/Forsyth School program to conduct a clinical investigation of the
development of obesity, metabolic syndrome and type 2 diabetes in
Kuwaiti children. During the five-year study, the body weight, height,
blood pressure and fitness were measured, oral disease was evaluated,
nutritional information was collected, questionnaires on sleep and
medical history were answered and saliva was collected for analysis.