Intake of sweet foods and counts of cariogenic microorganisms in obese and normal-weight women

Effect of adiposity status on salivary Streptococcus mutans and Streptococcus sobrinus

OBJECTIVES

To investigate the effect of adiposity status, salivary physicochemical parameters, and inflammatory biomarkers on the salivary abundance of the two main cariogenic bacteria Streptococcus mutans and Streptococcus sobrinus among Hong Kong adolescents.

SUBJECTS AND METHODS

This study included 180 adolescents aged 12-15 years from Hong Kong local secondary schools. Anthropometric measurements and oral health examinations were performed. Saliva samples were collected to measure salivary physicochemical parameters, protein biomarker levels, and salivary abundance of Streptococcus mutans, Streptococcus sobrinus, and total bacteria.

RESULTS

Adolescents with general overweight/obesity or central obesity had significantly higher salivary Streptococcus mutans abundance and total bacterial load, lower stimulated salivary flow rate, and lower secretory phospholipase A2 group IIA levels than the lean controls. Adolescents with general overweight/obesity (OR = 3.33; 95% CI: 1.28-8.65) and those with central obesity (OR = 2.47; 95% CI: 1.02-6.00) had a significantly higher chance of having high salivary abundance of Streptococcus mutans than the lean controls after adjusting for confounders, with a similar detection rate of salivary Streptococcus sobrinus.

CONCLUSION

General overweight or obesity and central obesity were associated with a high salivary abundance of Streptococcus mutans but had no significant effect on salivary Streptococcus sobrinus.

Salivary Microbiological and Gingival Health Status Evaluation of Adolescents With Overweight and Obesity: A Cluster Analysis

Given the high prevalence of obesity in children and adolescents, the investigation of early markers is of clinical importance to better manage this condition. Thus, the aim was to evaluate the cross-sectional relationship between salivary microbiota, gingival health status, and excess weight in adolescents. A total of 248 students (14-17 y; 119 girls) were included, free of caries lesions and periodontal pockets. Physical examination included measures of height, weight, and body fat percentage (%BF). Oral examination was performed to gather information on dental (DMFT index) and gingival health status. Unstimulated saliva was submitted to qPCR reactions to quantify Streptococcus mutans, Porphyromonas gingivalis, Bifidobacteria, and Streptococcus pneumoniae percentages and the NFKappaB expression. Two-way ANOVA was applied considering group (normal-weight/overweight/obesity) and sex factors, in addition to cluster analysis. Group effect was significant for %S. mutans (partial eta² = 0.20; p < 0.001) and %Bifidobacteria (partial eta² = 0.19; p < 0.001), with overweight and obesity groups showing the highest levels compared to normal-weight ones, with no significant sex effect. There was no difference in the frequency of gingivitis, P. gingivalis, and S. pneumoniae percentages or NFKappaB expression between groups. Cluster analysis generated three clusters according to body fat accumulation: "Higher %BF," "Moderate %BF," and "Lower %BF." "Higher %BF" cluster was characterized by higher body fat percentage and higher salivary %Bifidobacteria, while cluster "Lower %BF" was characterized by lower body fat percentage and lower frequency of gingivitis ("Moderate %BF" cluster was the contrast). According to nutritional status, a difference in salivary S. mutans and Bifidobacteria percentages was found, with overweight or obesity adolescents showing the highest percentages than normal-weight ones. Besides, a positive relationship between body fat accumulation and Bifidobacteria count was observed, indicating a possible interaction between oral bacteria communities and weight gain.

BMI, eating habits and sleep in relation to salivary counts of mutans streptococci in children - the IDEFICS Sweden study

OBJECTIVE

The objective of the present study was to investigate the association between salivary counts of mutans streptococci (MS) and children's weight status, while considering associated covariates. MS ferments carbohydrates from the diet and contributes to caries by lowering the pH in dental plaque. In adults, high counts of MS in saliva have been associated with overweight, but this has not been shown in children.

DESIGN

Cross-sectional study investigating salivary counts of MS, BMI Z-score, waist circumference, meal frequency, sugar propensity and sleep duration, in children.

SETTING

West Sweden.

SUBJECTS

Children (n 271) aged 4-11 years.

RESULTS

Medium-high counts of MS were positively associated with higher BMI Z-score (OR=1·6; 95% CI 1·1, 2·3). Positive associations were also found between medium-high counts of MS and more frequent meals per day (OR=1·5; 95% CI 1·1, 2·2), greater percentage of sugar-rich foods consumed (OR=1·1; 95% CI 1·0, 1·3) and female sex (OR=2·4; 95% CI 1·1, 5·4). A negative association was found between medium-high counts of MS and longer sleep duration (OR=0·5; 95% CI 0·3, 1·0).

CONCLUSIONS

BMI Z-score was associated with counts of MS. Promoting adequate sleep duration and limiting the intake frequency of sugar-rich foods and beverages could provide multiple benefits in public health interventions aimed at reducing dental caries and childhood overweight.

Clinical and biological indicators of dental caries and periodontal disease in adolescents with or without obesity

OBJECTIVE

This study aims to assess clinical, microbiological and inflammatory parameters as indicators for caries and periodontal disease in adolescents with obesity.

MATERIAL AND METHODS

Twenty-seven adolescents with obesity [body mass index (BMI) 37 ± 4 kg/m(2)] and 28 controls (BMI 20 ± 2 kg/m(2)) answered questionnaires and were investigated regarding salivary parameters, plaque pH drop after a 1-min glucose rinse, oral clinical parameters, inflammatory markers in gingival crevicular fluid (GCF) and sub-gingival mirobiota.

RESULTS

Compared with controls, adolescents with obesity had a lower stimulated salivary secretion rate (1.55 ± 0.63 vs. 2.05 ± 1.05 mL/min, p < 0.05), higher concentrations of secretory immunoglobulin A (sIgA) (p < 0.001), more decayed tooth surfaces (3.4 ± 6.6 vs. 0.8 ± 1.1, p < 0.05) and more gingivitis (p < 0.01) after controlling for possible confounders. Overall, similar snacking habits, plaque amounts and numbers of deep periodontal pockets were observed. Following the glucose rinse, a slightly more pronounced drop in plaque pH was observed in the obesity group (p > 0.05). No differences in sub-gingival inflammatory or microbial indicators were detected (p > 0.01).

CONCLUSIONS

More caries and gingival inflammation were observed in adolescents with obesity. Of the indicators tested, salivary secretion rate was lower and sIgA levels were higher in the obesity group. We are unable to confirm whether differences in caries and gingival inflammation are due to systemic changes that are associated with obesity or due to possible irregular dietary/oral hygiene habits.

CLINICAL RELEVANCE

Customised oral health preventive programmes and appropriate collaboration with medical personnel in selecting the best diet, medication and psychological support can help improve the general well-being, including oral health, of children with obesity. This may even reduce the risk of oral diseases.

Sweetness and food preference

Human desire for sweet taste spans all ages, races, and cultures. Throughout evolution, sweetness has had a role in human nutrition, helping to orient feeding behavior toward foods providing both energy and essential nutrients. Infants and young children in particular base many of their food choices on familiarity and sweet taste. The low cost and ready availability of energy-containing sweeteners in the food supply has led to concerns that the rising consumption of added sugars is the driving force behind the obesity epidemic. Low-calorie sweeteners are one option for maintaining sweet taste while reducing the energy content of children's diets. However, their use has led to further concerns that dissociating sweetness from energy may disrupt the balance between taste response, appetite, and consumption patterns, especially during development. Further studies, preferably based on longitudinal cohorts, are needed to clarify the developmental trajectory of taste responses to low-calorie sweeteners and their potential impact on the diet quality of children and youth.

Cariogenic Bacteria as Biomarkers for Sugar Intake

Cariogenic bacteria (lactobacilli and mutans streptococci) in saliva are possible biomarkers for sugar intake. We evaluated the strength of the evidence for an association between sugar intake and the two groups of bacteria, and concluded that there is a limited to moderately scientific basis for this association. Because of many confounding factors, bacteria counts can never be used as a precise measurement of sugar intake, but might still be useful on a group level.

Associations between salivary bacteria and reported sugar intake and their relationship with body mass index in women and their adolescent children

OBJECTIVE

To study associations between reported sugar intake and salivary bacteria (mutans streptococci, MS and lactobacilli, LB), and sugar intake in relation to body mass index (BMI), in women and adolescents.

DESIGN

Cross-sectional study. Habitual dietary intake was reported in a questionnaire and whole saliva samples were collected and cultivated.

SETTING

Stockholm, Sweden.

SUBJECTS

Four hundred and fourteen mothers and their 16-year-old children (57% girls).

RESULTS

Reported total sugar intake was significantly associated with LB in mothers (P = 0.001), but not in daughters and sons (P = 0.03 for mother-son interaction). When excluding lactose, the associations with LB and MS were significant in daughters (P = 0.032 and 0.005, respectively). High BMI and sugar intake from milk were independently associated with MS counts in mothers in a multiple regression model (R2 = 0.053). In daughters, sugar from beverages, candies/chocolates and fruits were all independently associated with MS counts (R2 = 0.074), whereas in sons, only mothers' MS counts were associated (R2 = 0.084). High BMI, low intake from cooked meals and high intake of candies/chocolates were all independently associated with LB in mothers (R2 = 0.076), while, except for candies/chocolates in daughters, no significant associations were found in children. BMI was significantly associated with bacteria counts in both mothers and children, whereas reported sugar intake was not.

CONCLUSION

The associations between reported sugar intake and bacteria were generally weak. In mothers and daughters, some significant associations were found, but not in sons. Bacteria counts, but not reported sugar intake, were positively associated with BMI.

The aetiology of childhood obesity: a review

Whilst the prevention of childhood obesity is the only viable, enduring, cost-effective solution to the obesity epidemic, effective methods for it remain elusive. Furthermore, strategies to influence obesogenic environments remain relatively unexplored. In order to be able to develop powerful population-level interventions and public health policies to prevent childhood obesity, it is important to understand its aetiology and those environments that are most amenable to measurable change. First, the present paper considers why we should be concerned about obesity in children, from both the perspective of the increased health risk to the individual and the high economic cost of treatment of obesity and related diseases, highlighting why the prevention of childhood obesity is important. Next, the determinants of health behaviour and the obesogenic environment are explored, which helps us to understand why the aetiology is so complex and that potential causal factors should not be considered in isolation, as the interaction between these factors is also important. The paper then considers the multi-factorial aetiology of childhood obesity and the rationale for the increasing trends in obesity that are evident, in order to understand what is changing in society and our children's behaviour that is triggering the positive energy balance leading to obesity. The review emphasises the need for multi-level approaches if we truly want to prevent childhood obesity. It also serves to highlight that there is a need to extend the current research base in order to build a well-founded framework to form the basis of a strategy for the prevention of childhood obesity.

The human sweet tooth

Humans love the taste of sugar and the word "sweet" is used to describe not only this basic taste quality but also something that is desirable or pleasurable, e.g., la dolce vita. Although sugar or sweetened foods are generally among the most preferred choices, not everyone likes sugar, especially at high concentrations. The focus of my group's research is to understand why some people have a sweet tooth and others do not. We have used genetic and molecular techniques in humans, rats, mice, cats and primates to understand the origins of sweet taste perception. Our studies demonstrate that there are two sweet receptor genes (TAS1R2 and TAS1R3), and alleles of one of the two genes predict the avidity with which some mammals drink sweet solutions. We also find a relationship between sweet and bitter perception. Children who are genetically more sensitive to bitter compounds report that very sweet solutions are more pleasant and they prefer sweet carbonated beverages more than milk, relative to less bitter-sensitive peers. Overall, people differ in their ability to perceive the basic tastes, and particular constellations of genes and experience may drive some people, but not others, toward a caries-inducing sweet diet. Future studies will be designed to understand how a genetic preference for sweet food and drink might contribute to the development of dental caries.

Intake of sweet foods and counts of cariogenic microorganisms in relation to body mass index and psychometric variables in women

OBJECTIVE

As a part of the SPAWN (Stockholm Pregnancy and Women's Nutrition) study, the intake of sweet foods (habitual and pre-menstrual intakes) and the number of cariogenic microorganisms in saliva was analysed in relation to body mass index (BMI) and psychometric variables.

DESIGN

A cross-sectional study.

SUBJECTS

Three hundred and sixty-two women with a median BMI of 24.2 kg/m(2) (range 17.5-47.8) and 45 y of age (range 34-64).

METHODS

A questionnaire of sweet food intake, salivary counts of mutans streptococci and lactobacilli and a self-rating scale on psychometric variables (CPRS-S-A).

RESULTS

The number of mutans streptococci correlated with BMI (P<0.05), indirectly indicating a higher intake of sweet foods in obese women. The reported energy intake of sweet foods (more specifically the intake of chocolate), correlated with CPRS scores (P<0.01), indicating that women with more severe psychiatric symptomatology have higher intakes of sweet foods.

CONCLUSIONS

This study suggests that women with higher CPRS score have higher energy intakes of sweet foods, indicating a possible link between mood regulation and the intake of sweet food.

SPONSORSHIP

Karolinska Institute Research Funds.