Relationships between the response of the sweet taste receptor, salivation toward sweeteners, and sweetness intensity

Effect of sweetened beverages intake on salivary aspartame, insulin and alpha-amylase levels: A single-blind study

The objective was to assess aspartame excretion in saliva and the salivary insulin, total protein (TP), and alpha-amylase (AMI) levels in response to the ingestion of sweetened beverages (sodium cyclamate, aspartame, acesulfame, and sucrose). Fifteen healthy participants were included in a single-blinded trial with the intake of Diet soft drink, Regular soft drink, Water + sweeteners, Low sucrose content (3.5 g), and Water (blank) in 5 different days. In each day, saliva was collected at T0 (fasting), T1 (15 min after test-drink intake), T2 (30 min), T3 (60 min), and T4 (120 min) for the measurement of salivary aspartame (HPLC), TP, AMI (ELISA assays) and insulin levels (chemiluminescence). Chi-square, Friedman, ANOVA and Spearman correlation tests were applied. The late-perceived sweet/sour residual flavor was reported at a frequency of 80%, 60% and 20% after ingestion of artificially sweetened drinks, beverages with sucrose, and plain water, respectively (p < 0.05). Aspartame was detected in saliva after artificially sweetened drinks intake, with highest area under the peak for the Diet soft drink (p = 0.014). No change was observed for TP and AMI levels during the 120 min. Insulin levels increased 1 h after soft-drinks ingestion (regular and diet), while the levels did not change for Low sucrose content and Water + sweeteners test-drinks. Salivary aspartame correlated with insulin levels only after Diet soft drink intake (rho ≥ 0.7; p < 0.05). As aspartame can be detected in saliva and swallowed again until completely excreted, these results contribute to the knowledge of the biological fate of artificial sweeteners and the study of health outcomes.

Effect of continuous sweet gustatory stimulation on salivary flow rate over time

OBJECTIVE

This study aimed to determine changes in saliva secretion and subjective taste intensity during a sustained period with continuous gustatory stimulation.

DESIGN

Twenty-two healthy adults participated in this study. The selected taste solutions were aspartame, sucralose, and acesulfame potassium, which are nonnutritive sweeteners. The concentrations of sucralose1 and acesulfame potassium were set to show the same sweetness intensity as aspartame. Sucralose2 was twice the concentration of sucralose1. The solution was continuously fed into the oral cavity at a flow rate of 0.04 mL / min through a neck-worn precise infusion system. The salivary flow rate (g/min) after 10 min of intraoral water supply from the device was used as the baseline. Salivary flow rate, subjective taste intensity evaluated by the visual analog scale (VAS), and salivary flow rate relative to the baseline were recorded at 10, 30, 60, and 120 min after the start of the test.

RESULTS

In the aspartame, sucralose1, and sucralose2 groups, the salivary flow rate increased significantly from 10 min to 120 min after the start of the test when compared to the rate at baseline (p < 0.05). The relative salivary flow rate increased and the VAS value decreased significantly over time and were affected by the time factor (p < 0.001, p = 0.013, respectively) but not by the sweetener-group factor and the interaction effects.

CONCLUSIONS

Continuous gustatory stimulation may maintain increased salivary production for a sustained period.

A Fresh Look at Mouthwashes-What Is Inside and What Is It For?

Mouthwashes are a very popular additional oral hygiene element and there are plenty of individual products, whose compositions are in a state of flux. The aim of our study was to investigate the compositions of mouthwashes and their functions, as well as to discuss their effectiveness in preventing and curing oral diseases and side effects. We searched for mouthwashes available on the market in Poland. We identified 241 individual mouthwash products. The extraction of compositions was performed and functions of the ingredients were assessed. Then, analysis was performed. The evaluation revealed that there are plenty of ingredients, but a typical mouthwash is a water–glycerine mixture and consists of additional sweetener, surfactant, preservative, and some colourant and flavouring agent, as well as usually having two oral health substances, anticaries sodium fluoride and antimicrobial essential oils. The effectiveness or side effects of several substances of mouthwashes were thoroughly discussed. We recommend not multiplying individual mouthwash products and their ingredients beyond medical or pharmaceutical necessity, especially without scientific proof.