Impact of Dairy Products and Plant-Based Alternatives on Dental Health: Food Matrix Effects

Dairy Matrix Effects: Physicochemical Properties Underlying a Multifaceted Paradigm

When food products are often considered only as a source of individual nutrients or a collection of nutrients, this overlooks the importance of interactions between nutrients, but also interactions between nutrients and other constituents of food, i.e., the product matrix. This product matrix, which can be defined as 'The components of the product, their interactions, their structural organization within the product and the resultant physicochemical properties of the product', plays a critical role in determining important product properties, such as product stability, sensory properties and nutritional and health outcomes. Such matrix effects can be defined as 'the functional outcome of specific component(s) as part of a specific product matrix'. In this article, dairy matrix effects are reviewed, with particular emphasis on the nutrition and health impact of dairy products. Such matrix effects are critical in explaining many effects of milk and dairy products on human nutrition and health that cannot be explained solely based on nutrient composition. Examples hereof include the low glycemic responses of milk and dairy products, the positive impact on dental health, the controlled amino acid absorption and the absence of CVD risk despite the presence of saturated fatty acids. Particularly, the changes occurring in the stomach, including, e.g., coagulation of casein micelles and creaming of aggregated fat globules, play a critical role in determining the kinetics of nutrient release and absorption.

Changes in gut microbiota and lactose intolerance symptoms before and after daily lactose supplementation in individuals with the lactase nonpersistent genotype

BACKGROUND

Approximately 70%-100% of the Asian adult population is lactase nonpersistent (LNP). The literature shows that many individuals with the LNP-genotype can consume ≤12 g of lactose without experiencing gastrointestinal discomfort. Repetitive consumption of lactose may reduce intolerance symptoms via adaptation of the gut microbiota.

OBJECTIVE

This study aimed to assess the effects of daily consumption of incremental lactose doses on microbiota composition and function, and intolerance symptoms.

METHODS

Twenty-five healthy adults of Asian origin, carrying the LNP-genotype were included in this 12-wk before and after intervention trial. Participants consumed gradually increasing lactose doses from 3 to 6 g to 12 g twice daily, each daily dose of 6 g, 12 g, or 24 g being provided for 4 consecutive weeks. Participants handed-in repeated stool samples and underwent a 25 g lactose challenge hydrogen breath test (HBT) before and after the 12-wk intervention. Daily gastrointestinal symptoms and total symptom scores (TSSs) during the lactose challenge were recorded.

RESULTS

A significant increase from 5.5% ± 7.6% to 10.4% ± 9.6% was observed in Bifidobacterium relative abundance after the intervention (P = 0.009), accompanied by a 2-fold increase (570 ± 269 U/g; P < 0.001) in fecal β-galactosidase activity compared with baseline (272 ± 158 U/g). A 1.5-fold decrease (incremental area under the curve; P = 0.01) in expired hydrogen was observed during the second HBT (38 ± 35 ppm·min), compared with the baseline HBT (57 ± 38 ppm·min). There was a nonsignificant decrease in TSS (10.6 ± 8.3 before compared with 8.1 ± 7.2 after intervention; P = 0.09). Daily consumption of lactose was well tolerated, with mild to no gastrointestinal complaints reported during the intervention.

CONCLUSIONS

Increased levels of Bifidobacterium indicate an adaptation of the gut microbiota upon repetitive consumption of incremental doses of lactose, which was well tolerated as demonstrated by reduced expired hydrogen concentrations during the second 25-g lactose HBT. Bifidobacteria metabolize lactose without gas production thereby potentially reducing intestinal gas formation in the gut of individuals with the LNP-genotype. This increased lactose tolerance possibly lifts the necessity to remove nutrient-rich dairy foods completely from the diet. The trial is registered at the International Clinical Trials Registry Platform: NL9516. The effect of dietary lactose in lactase nonpersistent individuals on gut microbiota.

Unlocking the potential of probiotic administration in caries management: a systematic review

BACKGROUND

The use of prebiotics and/or probiotic bacteria with the potential to modulate the oral ecosystem may play an important role in the prevention and management of dental caries. To assess the evidence of the potential of pre/probiotics both in the prevention and treatment of dental caries, we focused on the PICO question "In individuals with caries, after probiotic administration, is there an improvement in outcomes directly related to caries risk and development?".

METHODS

An extensive systematic search was conducted in electronic databases PubMed, Web of Science, Scopus and Cochrane, to identify articles with relevant data. This systematic review included trials performed in Humans; published in English; including the observation of patients with caries, with clear indication of the probiotic used and measuring the outcomes directly involved with the cariogenic process, including the quantification of bacteria with cariogenic potential. To evaluate the methodological quality of the studies, the critical assessment tool from the Joanna Briggs Institute was used.

RESULTS

Eight hundred and fifty articles, potentially relevant, were identified. Following PRISMA guidelines 14 articles were included in this systematic review. Outcomes such as reduction of cariogenic microorganism counts, salivary pH, buffer capacity, and caries activity were assessed. The probiotic most often referred with beneficial results in dental caries outcomes is Lacticaseibacillus rhamnosus. Regarding the most used administration vehicle, in studies with positive effects on the caries management, probiotic supplemented milk could be considered the best administration vehicle.

CONCLUSIONS

Evidence suggests a beneficial effect of probiotic supplemented milk (Lacticaseibacillus rhamnosus) as an adjuvant for caries prevention and management. However, comparable evidence is scarce and better designed and comparable studies are needed.

Dietary Habits and Oral Hygiene as Determinants of the Incidence and Intensity of Dental Caries-A Pilot Study

OBJECTIVES

The aim of this study was to assess the influence of dietary and hygiene habits on the prevalence and intensity of dental caries. A group of 148 adults participated in the study.

METHODS

A self-administered nutrition and oral hygiene questionnaire was used to assess dietary habits and oral hygiene routine. A preventive diet index (PDI), a cariogenic diet index (CDI), and an oral health hygiene and prevention index (OHHPI) were created based on part of the questions. The intensity of dental caries among the respondents was investigated by the decayed, missing, and filled teeth index (DMFT), which was estimated on the basis of data obtained during the dental examination.

RESULTS

The study showed that 97% of the respondents had filled carious cavities, while untreated carious cavities were observed in up to 78% of the study participants. The respondents had an average consumption of preventive products and a low consumption of caries-stimulating foods. The preventive dietary index (PDI) value was higher in the female group than in the male group. A more frequent consumption of caries-inhibiting products was demonstrated by those declaring that they took various types of dietary supplements. The use of health-promoting sugar substitutes by the respondents was associated with a lower intensity of dental caries and a more frequent consumption of preventive products.

CONCLUSIONS

The analysis of the survey results indicates the need to implement educational activities aimed at increasing public awareness of the prevalence of dental caries among adults.

Effect of various types of milk on salivary pH among children: a pilot randomized controlled crossover trial

OBJECTIVE

This study aimed to evaluate salivary pH changes after consuming three types of milk in children aged 3-5 years. The null hypothesis was that no statistically significant difference would be noted in the salivary pH between high-protein, full-fat, and sweetened milk groups at different time points.

MATERIALS AND METHODS

This was a double-blind, pilot randomized controlled crossover trial. 30 Children have undergone three experimental sessions with a 1-week washout period. Each child was given 250 mL of one of the following types of milk: high-protein, full-fat, or sweetened milk. The salivary pH was measured at the baseline (t0) after 5 (t1), 10 (t2), 15 (t3), 30 (t4), and 60 (t5) minutes of milk consumption, using a pH saliva indicator strip.

RESULTS

There is a sharp drop in salivary pH after 5 min of sweetened (P < 0.05) and full-fat milk consumption (p < 0.05). However, the initial drop in the salivary pH was found to remain above the critical level. For the high-protein milk group, salivary pH decreased slightly after 5 min but was similar to that at the baseline (p = 0.573). In the high-protein milk group (p < 0.05), the salivary pH was slightly greater than the baseline value at t5.

CONCLUSIONS

The study shows an initial suggestion that milk is a non-cariogenic beverage, even when sugar is added. Furthermore, high-protein milk has a protective effect from dental caries.