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.