The Effects of Non-Nutritive Artificial Sweeteners, Aspartame and Sucralose, on the Gut Microbiome in Healthy Adults: Secondary Outcomes of a Randomized Double-Blinded Crossover Clinical Trial

Long-term metabolic effects of non-nutritive sweeteners

OBJECTIVE

Excessive consumption of added sugars has been linked to the rise in obesity and associated metabolic abnormalities. Non-nutritive sweeteners (NNSs) offer a potential solution to reduce sugar intake, yet their metabolic safety remains debated. This study aimed to systematically assess the long-term metabolic effects of commonly used NNSs under both normal and obesogenic conditions.

METHODS

To ensure consistent sweetness level and controlling for the acceptable daily intake (ADI), eight weeks old C57BL/6 male mice were administered with acesulfame K (ace K, 535.25 mg/L), aspartame (411.75 mg/L), sucralose (179.5 mg/L), saccharin (80 mg/L), or steviol glycoside (Reb M, 536.25 mg/L) in the drinking water, on the background of either regular or high-fat diets (in high fat diet 60% of calories from fat). Water or fructose-sweetened water (82.3.gr/L), were used as controls. Anthropometric and metabolic parameters, as well as microbiome composition, were analyzed following 20-weeks of exposure.

RESULTS

Under a regular chow diet, chronic NNS consumption did not significantly affect body weight, fat mass, or glucose metabolism as compared to water consumption, with aspartame demonstrating decreased glucose tolerance. In diet-induced obesity, NNS exposure did not increase body weight or alter food intake. Exposure to sucralose and Reb M led to improved insulin sensitivity and decreased weight gain. Reb M specifically was associated with increased prevalence of colonic Lachnospiracea bacteria.

CONCLUSIONS

Long-term consumption of commonly used NNSs does not induce adverse metabolic effects, with Reb M demonstrating a mild improvement in metabolic abnormalities. These findings provide valuable insights into the metabolic impact of different NNSs, aiding in the development of strategies to combat obesity and related metabolic disorders.

Impact of artificial sweeteners and rare sugars on the gut microbiome

Alternative sugars are often used as sugar substitutes because of their low calories and glycemic index. Recently, consumption of these sweeteners in diet foods and beverages has increased dramatically, raising concerns about their health effects. This review examines the types and characteristics of artificial sweeteners and rare sugars and analyzes their impact on the gut microbiome. In the section on artificial sweeteners, we have described the chemical structures of different sweeteners, their digestion and absorption processes, and their effects on the gut microbiota. We have also discussed the biochemical properties and production methods of rare sugars and their positive and negative effects on gut microbial communities. Finally, we have described how artificial sweeteners and rare sugars alter the gut microbiome and how these changes affect the gut environment. Our observations aim to improve our understanding regarding the potential health implications of the consumption of artificial sweeteners and low-calorie sugars.

Sucralose Influences the Productive Performance, Carcass Traits, Blood Components, and Gut Microflora Using 16S rRNA Sequencing of Growing APRI-Line Rabbits

This study investigated how sucralose influenced rabbit intestine and caecal microbial activity, blood parameters, growth performance, carcass characteristics, and digestibility. In total, 160 5-week-old rabbits from the APRI line weighing 563.29 gm were randomly assigned to four experimental groups with four replicates-5 males and 5 females in each. Four experimental groups were used, as follows: SUC1, SUC2, and SUC3 got 75, 150, and 300 mg of sucralose/kg body weight in water daily, while the control group ate a basal diet without supplements. The results showed that both the control and SUC1 groups significantly (p < 0.05) increased daily weight gain and final body weight. Sucralose addition significantly improved feed conversion ratio (p < 0.05) and decreased daily feed intake (gm/d). The experimental groups do not significantly differ in terms of mortality. Furthermore, nutrient digestibility was not significantly affected by sucralose treatment, with the exception of crud protein digestion, which was significantly reduced (p < 0.05). Additionally, without altering liver or kidney function, sucralose administration dramatically (p < 0.05) decreased blood serum glucose and triglyceride levels while increasing total lipids, cholesterol, and malonaldehyde in comparison to the control group. Furthermore, the addition of sucrose resulted in a significant (p < 0.05) increase in the count of total bacteria, lactobacillus, and Clostridium spp., and a decrease in the count of Escherichia coli. Further analysis using 16S rRNA data revealed that sucralose upregulated the expression of lactobacillus genes but not that of Clostridium or E. Coli bacteria (p < 0.05). Therefore, it could be concluded that sucralose supplementation for rabbits modifies gut microbiota and boosts beneficial bacteria and feed conversion ratios without side effects. Moreover, sucralose could decrease blood glucose and intensify hypercholesterolemia and should be used with caution for human consumption.

Artificial sweeteners and their implications in diabetes: a review

Diabetes is a significant global health concern, highlighting the critical role of dietary strategies in its management and prevention. Artificial sweeteners (ASs), due to their capacity to provide sweetness without contributing to caloric intake, have emerged as a potential tool in diabetes management. This review thoroughly examines the nuanced relationship between artificial sweeteners and diabetes, addressing their benefits and potential risks. ASs have been shown to aid in weight management, a key factor in reducing diabetes risk, and do not impact immediate blood glucose levels, offering improved glucose control for individuals with diabetes. Beyond these benefits, however, artificial sweeteners may interact complexly with gut microbiota, potentially altering its composition and affecting metabolic health. This interaction introduces concerns regarding insulin sensitivity and the risk of insulin resistance, with studies reporting conflicting findings. This comprehensive review highlights the importance of a nuanced approach to understanding the implications of artificial sweeteners in diabetes management. Given the mixed evidence on their health effects, there is a clear need for further research to fully elucidate the role of artificial sweeteners in metabolic health and their suitability as part of dietary interventions for diabetes.

Ultra-processed foods and food additives in gut health and disease

Ultra-processed foods (UPFs) and food additives have become ubiquitous components of the modern human diet. There is increasing evidence of an association between diets rich in UPFs and gut disease, including inflammatory bowel disease, colorectal cancer and irritable bowel syndrome. Food additives are added to many UPFs and have themselves been shown to affect gut health. For example, evidence shows that some emulsifiers, sweeteners, colours, and microparticles and nanoparticles have effects on a range of outcomes, including the gut microbiome, intestinal permeability and intestinal inflammation. Broadly speaking, evidence for the effect of UPFs on gut disease comes from observational epidemiological studies, whereas, by contrast, evidence for the effect of food additives comes largely from preclinical studies conducted in vitro or in animal models. Fewer studies have investigated the effect of UPFs or food additives on gut health and disease in human intervention studies. Hence, the aim of this article is to critically review the evidence for the effects of UPF and food additives on gut health and disease and to discuss the clinical application of these findings.

Ultra-Processed Foods: A Narrative Review of the Impact on the Human Gut Microbiome and Variations in Classification Methods

Ultra-processed foods (UPFs) are foods that are industrially processed and are often pre-packaged, convenient, energy-dense, and nutrient-poor. UPFs are widespread in the current Western diet and their proposed contribution to non-communicable diseases such as obesity and cardiovascular disease is supported by numerous studies. UPFs are hypothesized to affect the body in multiple ways, including by inducing changes in the gut microbiome. This review summarizes the available research on the effect of UPFs on the gut microbiome. We also review current usage of the NOVA food classification system in randomized controlled trials and observational studies and how its implementation effects UPF research. Despite some differences in methodology between studies, results often associate UPF consumption with a number of negative health consequences. There are attempts to standardize a UPF classification system; however, reaching and implementing a consensus is difficult. Future studies focusing on the mechanisms by which UPFs effect the body, including through the microbiome and metabolome, will be essential to refine our understanding of the effects of UPFs on human health.

Effect of steviol glycosides as natural sweeteners on glucose metabolism in adult participants

Steviol glycosides (SGs) are recognized as safe natural sweeteners; however, evidence from randomized controlled trials (RCTs) showed an inconclusive effect of SGs on glucose metabolism in adult participants. We aimed to conduct a systematic review and meta-analysis of RCTs to assess the effect of SGs on glucose metabolism. We systematically searched PubMed, Web of Science and EMBASE to include eligible RCTs. Our primary outcomes were differences between SGs and the control group with respect to changes in blood glucose from the baseline to the end of intervention (including fasting blood glucose [FBG], and HbA1c measurements). A random-effects meta-analysis was conducted for data synthesis to calculate the pooled mean difference (MD). There were twelve RCTs included for analyses with a total of 871 participants (48% females). A significant effect of SGs on FBG (MD = -4.10 mg dl-1, 95% CI -6.55 to -1.65) was found, while no significant difference in HbA1c (MD = 0.01%, 95% CI -0.12% to 0.13%) was observed between SGs and controls. The whole quality of evidence was rated as low. Subgroup analyses demonstrated favorable effects of SGs on FBG in participants aged ≤50 years, those without diabetes mellitus (DM) or hypertension at the baseline, and overweight and obese adults. Sensitivity analyses yielded results largely similar to the main findings. To conclude, SGs are found to produce significant improvement in glucose metabolism in adult participants when compared with the control. More evidence is required to further clarify and support the benefit of SGs as a sugar substitute for glucose metabolism.

The Development and Evaluation of a Literature-Based Dietary Index for Gut Microbiota

The aim of the study was to develop and evaluate a novel dietary index for gut microbiota (DI-GM) that captures dietary composition related to gut microbiota profiles. We conducted a literature review of longitudinal studies on the association of diet with gut microbiota in adult populations and extracted those dietary components with evidence of beneficial or unfavorable effects. Dietary recall data from the National Health and Nutrition Examination Survey (NHANES, 2005-2010, n = 3812) were used to compute the DI-GM, and associations with biomarkers of gut microbiota diversity (urinary enterodiol and enterolactone) were examined using linear regression. From a review of 106 articles, 14 foods or nutrients were identified as components of the DI-GM, including fermented dairy, chickpeas, soybean, whole grains, fiber, cranberries, avocados, broccoli, coffee, and green tea as beneficial components, and red meat, processed meat, refined grains, and high-fat diet (≥40% of energy from fat) as unfavorable components. Each component was scored 0 or 1 based on sex-specific median intakes, and scores were summed to develop the overall DI-GM score. In the NHANES, DI-GM scores ranged from 0-13 with a mean of 4.8 (SE = 0.04). Positive associations between DI-GM and urinary enterodiol and enterolactone were observed. The association of the novel DI-GM with markers of gut microbiota diversity demonstrates the potential utility of this index for gut health-related studies.

Comparison of a Daily Steviol Glycoside Beverage compared with a Sucrose Beverage for Four Weeks on Gut Microbiome in Healthy Adults

BACKGROUND

Recent studies suggest that some nonnutritive sweeteners (NNS) have deleterious effects on the human gut microbiome (HGM). The effect of steviol glycosides on the HGM has not been well studied.

OBJECTIVE

We aimed to evaluate the effects of stevia- compared with sucrose-sweetened beverages on the HGM and fecal short-chain fatty acid (SCFA) profiles.

METHODS

Using a randomized, double-blinded, parallel-design study, n = 59 healthy adults [female/male, n = 36/23, aged 31±9 y, body mass index (BMI): 22.6±1.7 kg/m2] consumed 16 oz of a beverage containing either 25% of the acceptable daily intake (ADI) of stevia or 30 g of sucrose daily for 4 weeks followed by a 4-week washout. At weeks 0 (baseline), 4, and 8, the HGM was characterized via shotgun sequencing, fecal SCFA concentrations were measured using ultra-high performance liquid chromatography-tandem mass spectrometry and anthropometric measurements, fasting serum glucose, insulin and lipids, blood pressure, pulse, and 3-d diet records were obtained.

RESULTS

There were no significant differences in the HGM or fecal SCFA between the stevia and sucrose groups at baseline (P > 0.05). At week 4 (after intervention), there were no significant differences in the HGM at the phylum, family, genus, or species level between the stevia and sucrose groups and no significant differences in fecal SCFA. At week 4, BMI had increased by 0.3 kg/m2 (P = 0.013) in sucrose compared with stevia, but all other anthropometric and cardiometabolic measures and food intake did not differ significantly (P > 0.05). At week 8 (after washout), there were no significant differences in the HGM, fecal SFCA, or any anthropometric or cardiometabolic measure between the stevia and sucrose groups (P > 0.05).

CONCLUSIONS

Daily consumption of a beverage sweetened with 25% of the ADI of stevia for 4 weeks had no significant effects on the HGM, fecal SCFA, or fasting cardiometabolic measures, compared with daily consumption of a beverage sweetened with 30 g of sucrose.

TRIAL REGISTRATION

clinicaltrials.gov as NCT05264636.

Consumption of the Non-Nutritive Sweetener Stevia for 12 Weeks Does Not Alter the Composition of the Human Gut Microbiota

The use of non-nutritive sweeteners (NNSs) as an alternative to caloric sugars has increased in recent years. Stevia is an NNS that has demonstrated beneficial effects on appetite and energy intake. However, the impact on the gut microbiota is not well understood. Therefore, we investigated how regular consumption of stevia, for up to 12 weeks, impacts the human gut microbiota. Healthy subjects with a normal body mass index participated in our study; the stevia group (n = 14) was asked to consume five drops of stevia twice daily, compared to control participants (n = 13). Faecal samples collected before and after treatment were analysed by 16S rRNA gene sequencing. Stevia did not cause significant changes in the alpha or beta diversity when compared to the control groups. When the relative abundances of taxa were investigated, no clear differences were detected. Conversely, a random forest analysis correctly associated the gut microbiome with the control and stevia groups with an average of 75% accuracy, suggesting that there are intrinsic patterns that could discriminate between control and stevia use. However, large-scale changes in the gut microbiota were not apparent in this study, and, therefore, our data suggest that stevia does not significantly impact the gut microbiota.

Sweet, bloody consumption - what we eat and how it affects vascular ageing, the BBB and kidney health in CKD

In today's industrialized society food consumption has changed immensely toward heightened red meat intake and use of artificial sweeteners instead of grains and vegetables or sugar, respectively. These dietary changes affect public health in general through an increased incidence of metabolic diseases like diabetes and obesity, with a further elevated risk for cardiorenal complications. Research shows that high red meat intake and artificial sweeteners ingestion can alter the microbial composition and further intestinal wall barrier permeability allowing increased transmission of uremic toxins like p-cresyl sulfate, indoxyl sulfate, trimethylamine n-oxide and phenylacetylglutamine into the blood stream causing an array of pathophysiological effects especially as a strain on the kidneys, since they are responsible for clearing out the toxins. In this review, we address how the burden of the Western diet affects the gut microbiome in altering the microbial composition and increasing the gut permeability for uremic toxins and the detrimental effects thereof on early vascular aging, the kidney per se and the blood-brain barrier, in addition to the potential implications for dietary changes/interventions to preserve the health issues related to chronic diseases in future.

Consumption of sucralose- and acesulfame-potassium-containing diet soda alters the relative abundance of microbial taxa at the species level: findings of two pilot studies

Sucralose and acesulfame-potassium consumption alters gut microbiota in rodents, with unclear effects in humans. We examined effects of three-times daily sucralose- and acesulfame-potassium-containing diet soda consumption for 1 (n = 17) or 8 (n = 8) weeks on gut microbiota composition in young adults. After 8 weeks of diet soda consumption, the relative abundance of Proteobacteria, specifically Enterobacteriaceae, increased; and, increased abundance of two Proteobacteria taxa was also observed after 1 week of diet soda consumption compared with sparkling water. In addition, three taxa in the Bacteroides genus increased following 1 week of diet soda consumption compared with sparkling water. The clinical relevance of these findings and effects of sucralose and acesulfame-potassium consumption on human gut microbiota warrant further investigation in larger studies. Clinical trial registration: NCT02877186 and NCT03125356.

Diet-microbiota associations in gastrointestinal research: a systematic review

Interactions between diet and gastrointestinal microbiota influence health status and outcomes. Evaluating these relationships requires accurate quantification of dietary variables relevant to microbial metabolism, however current dietary assessment methods focus on dietary components relevant to human digestion only. The aim of this study was to synthesize research on foods and nutrients that influence human gut microbiota and thereby identify knowledge gaps to inform dietary assessment advancements toward better understanding of diet-microbiota interactions. Thirty-eight systematic reviews and 106 primary studies reported on human diet-microbiota associations. Dietary factors altering colonic microbiota included dietary patterns, macronutrients, micronutrients, bioactive compounds, and food additives. Reported diet-microbiota associations were dominated by routinely analyzed nutrients, which are absorbed from the small intestine but analyzed for correlation to stool microbiota. Dietary derived microbiota-relevant nutrients are more challenging to quantify and underrepresented in included studies. This evidence synthesis highlights advancements needed, including opportunities for expansion of food composition databases to include microbiota-relevant data, particularly for human intervention studies. These advances in dietary assessment methodology will facilitate translation of microbiota-specific nutrition therapy to practice.

Effect of low-and non-calorie sweeteners on the gut microbiota: A review of clinical trials and cross-sectional studies

Use of non-nutritive sweeteners (NNSs) has increased worldwide in recent decades. However, evidence from preclinical studies shows that sweetener consumption may induce glucose intolerance through changes in the gut microbiota, which raises public health concerns. As studies conducted on humans are lacking, the aim of this review was to gather and summarize the current evidence on the effects of NNSs on human gut microbiota. Only clinical trials and cross-sectional studies were included in the review. Regarding NNSs (i.e, saccharin, sucralose, aspartame, and stevia), only two of five clinical trials showed significant changes in gut microbiota composition after the intervention protocol. These studies concluded that saccharin and sucralose impair glycemic tolerance. In three of the four cross-sectional studies an association between NNSs and the microbial composition was observed. All three clinical trials on polyols (i.e, xylitol) showed prebiotic effects on gut microbiota, but these studies had multiple limitations (publication date, dosage, duration) that jeopardize their validity. The microbial response to NNSs consumption could be strongly mediated by the gut microbial composition at baseline. Further studies in which the potential personalized microbial response to NNSs consumption is acknowledged, and that include longer intervention protocols, larger cohorts, and more realistic sweetener dosage are needed to broaden these findings.

Consuming artificial sweeteners may alter the structure and function of duodenal microbial communities

Studies using stool samples suggest that non-sugar sweetener (NSS) consumption affects gut microbiome composition. However, stool does not represent the entire gut. We analyzed the duodenal luminal microbiome in subjects consuming non-aspartame non-sugar sweeteners (NANS, N = 35), aspartame only (ASP, N = 9), and controls (CON, N = 55) and the stool microbiome in a subset (N = 40). Duodenal alpha diversity was decreased in NANS vs. CON. Duodenal relative abundance (RA) of Escherichia, Klebsiella, and Salmonella (all phylum Proteobacteria) was lower in both NANS and ASP vs. CON, whereas stool RA of Escherichia, Klebsiella, and Salmonella was increased in both NANS and ASP vs. CON. Predicted duodenal microbial metabolic pathways altered in NANS vs. CON included polysaccharides biosynthesis and D-galactose degradation, whereas cylindrospermopsin biosynthesis was significantly enriched in ASP vs. CON. These findings suggest that consuming non-sugar sweeteners may significantly alter microbiome composition and function in the metabolically active small bowel, with different alterations seen in stool.

Learning and memory deficits produced by aspartame are heritable via the paternal lineage

Environmental exposures produce heritable traits that can linger in the population for one or two generations. Millions of individuals consume substances such as artificial sweeteners daily that are declared safe by regulatory agencies without evaluation of their potential heritable effects. We show that consumption of aspartame, an FDA-approved artificial sweetener, daily for up to 16-weeks at doses equivalent to only 7-15% of the FDA recommended maximum daily intake value (equivalent to 2-4 small, 8 oz diet soda drinks per day) produces significant spatial learning and memory deficits in mice. Moreover, the cognitive deficits are transmitted to male and female descendants along the paternal lineage suggesting that aspartame's adverse cognitive effects are heritable, and that they are more pervasive than current estimates, which consider effects in the directly exposed individuals only. Traditionally, deleterious environmental exposures of pregnant and nursing women are viewed as risk factors for the health of future generations. Environmental exposures of men are not considered to pose similar risks. Our findings suggest that environmental exposures of men can produce adverse impact on cognitive function in future generations and demonstrate the need for considering heritable effects via the paternal lineage as part of the regulatory evaluations of artificial sweeteners.

Nutritional aspects of inflammatory bowel disease

INTRODUCTION

The number of people diagnosed with inflammatory bowel disease (IBD) continues to increase in most parts of the world. Although the exact etiology of this chronic intestinal disease is not fully understood, nutritional factors appear to play key roles. Furthermore, individuals with IBD are at increased risk of adverse nutritional impacts, including micronutrient deficiencies.

AREAS COVERED

This review aims to summarize recent reports focusing on nutritional factors relevant to the development of IBD and to also review data on nutritional deficiencies seen in individuals with IBD.

EXPERT OPINION

The typical western diet, characterized by high-fat/high-sugar foods, along with food additives, appears to contribute to the etiopathogenesis of IBD. In contrast, some reports indicate that some foods are likely protective. However, there are inconsistencies in the currently available data, reflecting study design and other confounding factors. Furthermore, some of the conclusions are inferred from animal or in vitro studies. The presence of IBD can compromise the nutrition of individuals with one of these disorders: ongoing monitoring is critical. Nutrition and diet in the setting of IBD remain key areas for further and ongoing study.

Artificially Sweetened Beverages and Health Outcomes: An Umbrella Review

The consumption of artificially sweetened beverages (ASBs) is increasing in some countries. However, some meta-analyses have found that habitual consumers of ASBs (compared with low or no consumption) had an increased risk on some health outcomes. We performed an umbrella review of meta-analyses to grade the credibility of the evidence of claimed observational associations between ASBs and health outcomes. Data were searched in Web of Science, Embase, and PubMed for systematic reviews published up to 25 May 2022, examining association between ASBs and any health outcomes. Certainty of the evidence for each health outcome was obtained based on statistical results of tests used in umbrella reviews. The AMSTAR-2 tool (16 items) was used to identify high-quality systematic reviews. Answers of each item were rated as yes, no, or partial yes (for a partial adherence to the standard). We included data from 11 meta-analyses with unique population, exposure, comparison group, outcome obtained from 7 systematic reviews (51 cohort studies and 4 case-control studies). ASBs were associated with higher risk of obesity, type 2 diabetes, all-cause mortality, hypertension, and cardiovascular disease incidence (supported by highly suggestive evidence). Evidence for other outcomes (colorectal cancer, pancreatic cancer, gastrointestinal cancer, cancer mortality, cardiovascular mortality, chronic kidney disease, coronary artery disease, and stroke) was weak. Results of the quality assessment of systematic reviews using AMSTAR-2 showed some notable deficiencies: unclear sources of funding of eligible studies and lack of predefined study protocols to guide authors. The consumption of ASBs was associated with a higher risk of obesity, type 2 diabetes, all-cause mortality, hypertension, and cardiovascular disease incidence. However, further cohort studies and clinical trials in humans are still needed to understand the impact of ASBs on health outcomes.

The Impact of Nutrition, Physical Activity, Beneficial Microbes, and Fecal Microbiota Transplant for Improving Health

The recognition that microbes are integral to human life has led to studies on how to manipulate them in favor of health outcomes. To date, there has been no conjoint recommendation for the intake of dietary compounds that can complement the ingested organisms in terms of promoting an improved health outcome. The aim of this review is to discuss how beneficial microbes in the form of probiotics, fermented foods, and donor feces are being used to manage health. In addition, we explore the rationale for selecting beneficial microbial strains and aligning diets to accommodate their propagation in the gut. A pilot clinical trial design is presented to examine the effects of probiotics and exercise in patients with phenylketonuria (PKU); it is the most common inborn error of amino acid metabolism, and it is a complication that requires lifelong dietary intervention. The example design is provided to illustrate the importance of using omics technology to see if the intervention elevates neuroactive biogenic amines in the plasma; increases the abundance of Eubacterium rectale, Coprococcus eutactus, Akkermansia muciniphila, or Butyricicoccus; and increases Escherichia/Shigella in the gut, all as markers of improved health. By emphasizing the combined importance of diet, microbial supplements, and the gut microbiome, we hope that future studies will better align these components, not only to improve outcomes, but also to enhance our understanding of the mechanisms.

Effects of ultra-processed foods on the microbiota-gut-brain axis: The bread-and-butter issue

The topic of gut microbiota and the microbiota-gut-brain (MGB) axis has become the forefront of research and reports in the past few years. The gut microbiota is a dynamic interface between the environment, food, and the host, reflecting the health status as well as maintaining normal physiological metabolism. Modern ultra-processed foods (UPF) contain large quantities of saturated and trans fat, added sugar, salt, and food additives that seriously affect the gut and physical health. In addition, these unhealthy components directly cause changes in gut microbiota functions and microbial metabolism, subsequently having the potential to impact the neural network. This paper reviews an overview of the link between UPF ingredients and the MGB axis. Considerable studies have examined that high intake of trans fat, added sugar and salt have deleterious effects on gut and brain functions, but relatively less focus has been placed on the impact of food additives on the MGB axis. Data from several studies suggest that food additives might be linked to metabolic diseases and inflammation. They may also alter the gut microbiota composition and microbial metabolites, which potentially affect cognition and behavior. Therefore, we emphasize that food additives including emulsifiers, artificial sweeteners, colorants, and preservatives interact with the gut microbiota and their possible effects on altering the brain and behavior based on the latest research. Future studies should further investigate whether gut dysbiosis mediates the effect of UPF on brain diseases and behavior. This thesis here sheds new light on future research pointing to the potentially detrimental effects of processed food consumption on brain health.

Beverage consumption and mortality among adults with type 2 diabetes: prospective cohort study

OBJECTIVE

To investigate the intake of specific types of beverages in relation to mortality and cardiovascular disease (CVD) outcomes among adults with type 2 diabetes.

DESIGN

Prospective cohort study.

SETTING

Health professionals in the United States.

PARTICIPANTS

15 486 men and women with a diagnosis of type 2 diabetes at baseline and during follow-up (Nurses' Health Study: 1980-2018; and Health Professionals Follow-Up Study: 1986-2018). Beverage consumption was assessed using a validated food frequency questionnaire and updated every two to four years.

MAIN OUTCOME MEASURES

The main outcome was all cause mortality. Secondary outcomes were CVD incidence and mortality.

RESULTS

During an average of 18.5 years of follow-up, 3447 (22.3%) participants with incident CVD and 7638 (49.3%) deaths were documented. After multivariable adjustment, when comparing the categories of lowest intake of beverages with the highest intake, the pooled hazard ratios for all cause mortality were 1.20 (95% confidence interval 1.04 to 1.37) for sugar sweetened beverages (SSBs), 0.96 (0.86 to 1.07) for artificially sweetened beverages (ASBs), 0.98 (0.90 to 1.06) for fruit juice, 0.74 (0.63 to 0.86) for coffee, 0.79 (0.71 to 0.89) for tea, 0.77 (0.70 to 0.85) for plain water, 0.88 (0.80 to 0.96) for low fat milk, and 1.20 (0.99 to 1.44) for full fat milk. Similar associations were observed between the individual beverages and CVD incidence and mortality. In particular, SSB intake was associated with a higher risk of incident CVD (hazard ratio 1.25, 95% confidence interval 1.03 to 1.51) and CVD mortality (1.29, 1.02 to 1.63), whereas significant inverse associations were observed between intake of coffee and low fat milk and CVD incidence. Additionally, compared with those who did not change their consumption of coffee in the period after a diabetes diagnosis, a lower all cause mortality was observed in those who increased their consumption of coffee. A similar pattern of association with all cause mortality was also observed for tea, and low fat milk. Replacing SSBs with ABSs was significantly associated with lower all cause mortality and CVD mortality, and replacing SSBs, ASBs, fruit juice, or full fat milk with coffee, tea, or plain water was consistently associated with lower all cause mortality.

CONCLUSIONS

Individual beverages showed divergent associations with all cause mortality and CVD outcomes among adults with type 2 diabetes. Higher intake of SSBs was associated with higher all cause mortality and CVD incidence and mortality, whereas intakes of coffee, tea, plain water, and low fat milk were inversely associated with all cause mortality. These findings emphasize the potential role of healthy choices of beverages in managing the risk of CVD and premature death overall in adults with type 2 diabetes.

Effect of Non-Nutritive Sweeteners on the Gut Microbiota

The human gut microbiota, a complex community of microorganisms living in the digestive tract, consists of more than 1500 species distributed in more than 50 different phyla, with 99% of bacteria coming from about 30-40 species. The colon alone, which contains the largest population of the diverse human microbiota, can harbor up to 100 trillion bacteria. The gut microbiota is essential in maintaining normal gut physiology and health. Therefore, its disruption in humans is often associated with various pathological conditions. Different factors can influence the composition and function of the gut microbiota, including host genetics, age, antibiotic treatments, environment, and diet. The diet has a marked effect, impacting the gut microbiota composition, beneficially or detrimentally, by altering some bacterial species and adjusting the metabolites produced in the gut environment. With the widespread use of non-nutritive sweeteners (NNS) in the diet, recent investigations have focused on their effect on the gut microbiota as a mediator of the potential impact generated by gastrointestinal-related disturbances, such as insulin resistance, obesity, and inflammation. We summarized the results from pre-clinical and clinical studies published over the last ten years that examined the single effects of the most consumed NNS: aspartame, acesulfame-K, sucralose, and saccharin. Pre-clinical studies have given conflicting results for various reasons, including the administration method and the differences in metabolism of the same NNS among the different animal species. A dysbiotic effect of NNS was observed in some human trials, but many other randomized controlled trials reported a lack of significant impacts on gut microbiota composition. These studies differed in the number of subjects involved, their dietary habits, and their lifestyle; all factors related to the baseline composition of gut microbiota and their response to NNS. The scientific community still has no unanimous consensus on the appropriate outcomes and biomarkers that can accurately define the effects of NNS on the gut microbiota.

The dietary sweetener sucralose is a negative modulator of T cell-mediated responses

Artificial sweeteners are used as calorie-free sugar substitutes in many food products and their consumption has increased substantially over the past years1. Although generally regarded as safe, some concerns have been raised about the long-term safety of the consumption of certain sweeteners2-5. In this study, we show that the intake of high doses of sucralose in mice results in immunomodulatory effects by limiting T cell proliferation and T cell differentiation. Mechanistically, sucralose affects the membrane order of T cells, accompanied by a reduced efficiency of T cell receptor signalling and intracellular calcium mobilization. Mice given sucralose show decreased CD8+ T cell antigen-specific responses in subcutaneous cancer models and bacterial infection models, and reduced T cell function in models of T cell-mediated autoimmunity. Overall, these findings suggest that a high intake of sucralose can dampen T cell-mediated responses, an effect that could be used in therapy to mitigate T cell-dependent autoimmune disorders.

Rationale, Design and Participants Baseline Characteristics of a Crossover Randomized Controlled Trial of the Effect of Replacing SSBs with NSBs versus Water on Glucose Tolerance, Gut Microbiome and Cardiometabolic Risk in Overweight or Obese Adult SSB Consumer: Strategies to Oppose SUGARS with Non-Nutritive Sweeteners or Water (STOP Sugars NOW) Trial and Ectopic Fat Sub-Study

BACKGROUND

Health authorities are near universal in their recommendation to replace sugar-sweetened beverages (SSBs) with water. Non-nutritive sweetened beverages (NSBs) are not as widely recommended as a replacement strategy due to a lack of established benefits and concerns they may induce glucose intolerance through changes in the gut microbiome. The STOP Sugars NOW trial aims to assess the effect of the substitution of NSBs (the "intended substitution") versus water (the "standard of care substitution") for SSBs on glucose tolerance and microbiota diversity.

DESIGN AND METHODS

The STOP Sugars NOW trial (NCT03543644) is a pragmatic, "head-to-head", open-label, crossover, randomized controlled trial conducted in an outpatient setting. Participants were overweight or obese adults with a high waist circumference who regularly consumed ≥1 SSBs daily. Each participant completed three 4-week treatment phases (usual SSBs, matched NSBs, or water) in random order, which were separated by ≥4-week washout. Blocked randomization was performed centrally by computer with allocation concealment. Outcome assessment was blinded; however, blinding of participants and trial personnel was not possible. The two primary outcomes are oral glucose tolerance (incremental area under the curve) and gut microbiota beta-diversity (weighted UniFrac distance). Secondary outcomes include related markers of adiposity and glucose and insulin regulation. Adherence was assessed by objective biomarkers of added sugars and non-nutritive sweeteners and self-report intake. A subset of participants was included in an Ectopic Fat sub-study in which the primary outcome is intrahepatocellular lipid (IHCL) by 1H-MRS. Analyses will be according to the intention to treat principle.

BASELINE RESULTS

Recruitment began on 1 June 2018, and the last participant completed the trial on 15 October 2020. We screened 1086 participants, of whom 80 were enrolled and randomized in the main trial and 32 of these were enrolled and randomized in the Ectopic Fat sub-study. The participants were predominantly middle-aged (mean age 41.8 ± SD 13.0 y) and had obesity (BMI of 33.7 ± 6.8 kg/m²) with a near equal ratio of female: male (51%:49%). The average baseline SSB intake was 1.9 servings/day. SSBs were replaced with matched NSB brands, sweetened with either a blend of aspartame and acesulfame-potassium (95%) or sucralose (5%).

CONCLUSIONS

Baseline characteristics for both the main and Ectopic Fat sub-study meet our inclusion criteria and represent a group with overweight or obesity, with characteristics putting them at risk for type 2 diabetes. Findings will be published in peer-reviewed open-access medical journals and provide high-level evidence to inform clinical practice guidelines and public health policy for the use NSBs in sugars reduction strategies.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT03543644.

The Associations between Maternal Serum Aspartame and Sucralose and Metabolic Health during Pregnancy

OBJECTIVE

We aimed to investigate the associations between maternal serum aspartame/sucralose levels and metabolic health during pregnancy.

METHODS

A nested population-based case-control study was conducted in 109 women with and without gestational diabetes mellitus (GDM). Serum aspartame and sucralose levels were assessed using an ultraperformance liquid chromatography coupled to a tandem mass spectrometry system.

RESULTS

We detected the presence of circulating aspartame and sucralose in all participants at fasting. No differences in serum aspartame or sucralose levels were observed between GDM and non-GDM groups. In the fully-adjusted linear regression models, serum aspartame levels were positively associated with insulin resistance index, total cholesterol, and LDL cholesterol. In the fully-adjusted logistic regression models, higher serum aspartame levels were positively associated with elevated HbA1c, insulin resistance, hypercholesterolemia, and hyper-LDL cholesterolemia. In the GDM group, the significant associations between higher serum aspartame levels and elevated HbA1c, insulin resistance, and hypo-HDL cholesterolemia persisted, while positive associations were found between higher serum aspartame levels and insulin resistance and hyper-LDL cholesterolemia in the non-GDM group. Serum sucralose levels were negatively associated with HbA1c.

CONCLUSIONS

The study found that maternal serum aspartame levels were positively associated with insulin resistance index, total cholesterol, and LDL cholesterol during pregnancy. This finding provides the different effects of specific NNS on metabolic health during pregnancy.

Ultra-processed foods as a possible culprit for the rising prevalence of inflammatory bowel diseases

Inflammatory bowel diseases (IBD) are chronic inflammatory disorders of the gastrointestinal tract, and the exact pathogenesis is still unclear. It is believed that IBD develops in response to a complex interaction between the microbiota, environmental factors, and the immune system, in genetically predisposed individuals. Identifying these environmental factors will offer more insight in the development of the disease, and reveal new therapeutic targets for IBD patients. One of the environmental factors that has gained more interest over the last years is our diet. The prevalence of IBD has increased significantly and this increase is thought to be associated with a ‘Western diet', characterized by high intake of fats, added sugar, meat, and ultra-processed foods (UPFs). The UPFs now account for almost 50% of the energy intake in Westernized countries and are therefore an important characteristic of this Western diet. UPFs are characterized by higher amounts of salt, fat, sugar and the presence of different food additives. Epidemiological studies have found associations between UPF intake and a range of non-communicable diseases, including inflammatory bowel disease (IBD). Preclinical and clinical evidence suggest that non-nutritive ingredients and additives, present in UPFs, can negatively affect different components of the intestinal barrier, such as the microbiota, the mucus layer, the epithelium, and the immune cells in the lamina propria. Disruption of this barrier can cause the immune system to encounter an increased bacterial exposure, leading to an aberrant immune response. In this article, the available evidence on the possible role of UPFs and their components in the increasing incidence and prevalence of IBD is reviewed. These findings can be translated to the clinic and may be helpful to consider when giving dietary advice to IBD patients. A better understanding of the role of UPFs may lead to less restrictive diets for patients with IBD, hence increasing the dietary compliance and efficacy of exclusion diets.

Is the Use of Artificial Sweeteners Beneficial for Patients with Diabetes Mellitus? The Advantages and Disadvantages of Artificial Sweeteners

Artificial sweeteners have been developed as substitutes for sugar. Sucralose, acesulfame K (ACE K), aspartame, and saccharin are artificial sweeteners. Previously, artificial sweeteners were thought to be effective in treating obesity and diabetes. Human meta-analyses have reported that artificial sweeteners have no effect on body weight or glycemic control. However, recent studies have shown that artificial sweeteners affect glucose absorption in the intestinal tract as well as insulin and incretin secretion in humans and animals. Moreover, artificial sweeteners alter the composition of the microbiota and worsen the glycemic control owing to changes in the gut microbiota. The early intake of ACE K was also shown to suppress the taste response to sugar. Furthermore, a large cohort study showed that high artificial sweetener intake was associated with all-cause mortality, cardiovascular risk, coronary artery disease risk, cerebrovascular risk, and cancer risk. The role of artificial sweeteners in the treatment of diabetes and obesity should be reconsidered, and the replacement of sugar with artificial sweeteners in patients will require the long-term tracking of not only intake but also changes in blood glucose and weight as well as future guidance based on gut bacteria data. To utilize the beneficial properties of artificial sweeteners in treatment, further studies are needed.

Effects of sweeteners on host physiology by intestinal mucosal microbiota: Example-addition sweeteners in Qiweibaizhu Powder on intestinal mucosal microbiota of mice with antibiotic-associated diarrhea

In recent years, sweeteners have gained massive popularity under the trend of limiting sugar intake. Our previous study found that Qiweibaizhu Powder (QWBZP) could improve gut microbiota dysbiosis and has good efficacy in treating antibiotic-associated diarrhea (AAD). In this study, we investigated the effects of sucrose, sorbitol, xylitol, and saccharin on the intestinal mucosal microbiota of AAD mice treated with QWBZP. When the AAD model was constructed by being gavaged mixed antibiotic solution, Kunming mice were randomly assigned to seven groups: the control (mn) group, the ADD (mm) group, the QWBZP (mq) group, the saccharin + QWBZP (mc) group, the sucrose + QWBZP (ms) group, the xylito + QWBZP (mx) group, and the sorbitol + QWBZP (msl) group. Subsequently, 16S rRNA gene amplicon sequencing was used to analyze the intestinal mucosal microbiota composition and abundance. The results showed that feces from AAD mice were diluted and wet and improved diarrhea symptoms with QWBZP and sorbitol. In contrast, the addition of sucrose, saccharin, and xylitol delayed the healing of diarrhea. The relative abundance of intestinal mucosal microbiota showed Glutamicibacter, Robinsoniella, and Blautia were characteristic bacteria of the mx group, Candidatus Arthromitus, and Bacteroidales_S24-7_group as the typical bacteria of the mn group, Clostridium_innocuum_group as the distinct bacteria of the mm group. Mycoplasma and Bifidobacterium as the characteristic bacteria of the ms group. Correlation analysis of typical bacterial genera with metabolic functions shows that Blautia negatively correlates with D-Glutamine and D-glutamate metabolism. Bacteroidales_S24-7_group has a significant negative correlation with the Synthesis and degradation of ketone bodies. The study confirmed that sucrose, sorbitol, xylitol, and saccharin might further influence metabolic function by altering the intestinal mucosal microbiota. Compared to the other sweetener, adding sorbitol to QWBZP was the best therapeutic effect for AAD and increased the biosynthesis and degradation activities. It provides the experimental basis for applying artificial sweeteners in traditional Chinese medicine (TCM) as a reference for further rational development and safe use of artificial sweeteners.

Short-chain fatty acid: An updated review on signaling, metabolism, and therapeutic effects

Fatty acids are good energy sources (9 kcal per gram) that aerobic tissues can use except for the brain (glucose is an alternative source). Apart from the energy source, fatty acids are necessary for cell signaling, learning-related memory, modulating gene expression, and functioning as cytokine precursors. Short-chain fatty acids (SCFAs) are saturated fatty acids arranged as a straight chain consisting minimum of 6 carbon atoms. SCFAs possess various beneficial effects like improving metabolic function, inhibiting insulin resistance, and ameliorating immune dysfunction. In this review, we discussed the biogenesis, absorption, and transport of SCFA. SCFAs can act as signaling molecules by stimulating G protein-coupled receptors (GPCRs) and suppressing histone deacetylases (HDACs). The role of SCFA on glucose metabolism, fatty acid metabolism, and its effect on the immune system is also reviewed with updated details. SCFA possess anticancer, anti-diabetic, and hepatoprotective effects. Additionally, the association of protective effects of SCFA against brain-related diseases, kidney diseases, cardiovascular damage, and inflammatory bowel diseases were also reviewed. Nanotherapy is a branch of nanotechnology that employs nanoparticles at the nanoscale level to treat various ailments with enhanced drug stability, solubility, and minimal side effects. The SCFA functions as drug carriers, and nanoparticles were also discussed. Still, much research was not focused on this area. SCFA functions in host gene expression through inhibition of HDAC inhibition. However, the study has to be focused on the molecular mechanism of SCFA against various diseases that still need to be investigated.

Diet and nutrition against inflammatory bowel disease: Trick or treat(ment)?

Even if the relationships between nutrition and inflammatory bowel disease (IBD) remain underexplored, the current literature is providing, day by day, much more evidence on the effects of various diets in both prevention and treatment of such illnesses. Wrong dietary habits, together with other environmental factors such as pollution, breastfeeding, smoke, and/or antibiotics, are among the theoretical pathogenetic causes of IBD, whose multifactorial aetiology has been already confirmed. While some of these risk factors are potentially reversible, some others cannot be avoided, and efficient treatments become necessary to prevent IBD spread or recurrence. Furthermore, the drugs currently available for treatment of such disease provide low-to-no effect against the symptoms, making the illnesses still strongly disabling. Whether nutrition and specific diets will prove to effectively interrupt the course of IBD has still to be clarified and, in this sense, further research concerning the applications of such dietary interventions is still needed.

Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance

Non-nutritive sweeteners (NNS) are commonly integrated into human diet and presumed to be inert; however, animal studies suggest that they may impact the microbiome and downstream glycemic responses. We causally assessed NNS impacts in humans and their microbiomes in a randomized-controlled trial encompassing 120 healthy adults, administered saccharin, sucralose, aspartame, and stevia sachets for 2 weeks in doses lower than the acceptable daily intake, compared with controls receiving sachet-contained vehicle glucose or no supplement. As groups, each administered NNS distinctly altered stool and oral microbiome and plasma metabolome, whereas saccharin and sucralose significantly impaired glycemic responses. Importantly, gnotobiotic mice conventionalized with microbiomes from multiple top and bottom responders of each of the four NNS-supplemented groups featured glycemic responses largely reflecting those noted in respective human donors, which were preempted by distinct microbial signals, as exemplified by sucralose. Collectively, human NNS consumption may induce person-specific, microbiome-dependent glycemic alterations, necessitating future assessment of clinical implications.

Food Additives Associated with Gut Microbiota Alterations in Inflammatory Bowel Disease: Friends or Enemies?

During the 21st century, the incidence and prevalence of inflammatory bowel disease (IBD) is rising globally. Despite the pathogenesis of IBD remaining largely unclear, the interactions between environmental exposure, host genetics and immune response contribute to the occurrence and development of this disease. Growing evidence implicates that food additives might be closely related to IBD, but the involved molecular mechanisms are still poorly understood. Food additives may be categorized as distinct types in accordance with their function and property, including artificial sweeteners, preservatives, food colorant, emulsifiers, stabilizers, thickeners and so on. Various kinds of food additives play a role in modifying the interaction between gut microbiota and intestinal inflammation. Therefore, this review comprehensively synthesizes the current evidence on the interplay between different food additives and gut microbiome alterations, and further elucidates the potential mechanisms of food additives–associated microbiota changes involved in IBD.

Potential Effects of Sucralose and Saccharin on Gut Microbiota: A Review

Artificial sweeteners are additives widely used in our diet. Although there is no consensus, current evidence indicates that sucralose and saccharin could influence the gut microbiota. The aim of this study was to analyze the existing scientific evidence on the effects of saccharin and sucralose consumption on gut microbiota in humans. Different databases were used with the following search terms: sweeteners, non-caloric-sweeteners, sucralose, splenda, saccharin, sugartwin, sweet’n low, microbiota, gut microbiota, humans, animal model, mice, rats, and/or in vitro studies. In vitro and animal model studies indicate a dose-dependent relationship between the intake of both sweeteners and gut microbiota affecting both diversity and composition. In humans, long-term study suggests the existence of a positive correlation between sweetener consumption and some bacterial groups; however, most short-term interventions with saccharin and sucralose, in amounts below the ADI, found no significant effect on those groups, but there seems to be a different basal microbiota-dependent response of metabolic markers. Although studies in vitro and in animal models seem to relate saccharin and sucralose consumption to changes in the gut microbiota, more long-term studies are needed in humans considering the basal microbiota of participants and their dietary and lifestyle habits in all population groups. Toxicological and basal gut microbiota effects must be included as relevant factors to evaluate food safety and nutritional consequences of non-calorie sweeteners. In humans, doses, duration of interventions, and number of subjects included in the studies are key factors to interpret the results.

Understanding the mechanism underlying the anti-diabetic effect of dietary component: a focus on gut microbiota

Diabetes has become one of the biggest non-communicable diseases and threatens human health worldwide. The management of diabetes is a complex and multifaceted process including drug therapy and lifestyle interventions. Dietary components are essential for both diabetes management and health and survival of trillions of the gut microbiota (GM). Herein, we will discuss the relationship between diets and GM, the mechanism linking diabetes and gut dysbiosis, and the effects of dietary components (nutrients, phytochemicals, probiotics, food additives, etc.) on diabetes from the perspective of modulating GM. The GM of diabetic patients differs from that of health individuals and GM disorder contributes to the onset and maintenance of diabetes. Studies in humans and animal models consolidate that dietary component is a key regulator of diabetes and increasing evidence suggests that the alteration of GM plays a salient role in dietary interventions for diabetes. Given that diabetes is a major public health issue, especially that diabetes is linked with a high risk of mortality from COVID-19, this review provides compelling evidence for that targeting GM by dietary components is a promising strategy, and offers new insights into potential preventive or therapeutic approaches (dietary and pharmacological intervention) for the clinical management of diabetes.

Low Dose of Sucralose Alter Gut Microbiome in Mice

Sucralose is a non-nutritive artificial sweetener (NNS) used in foods or beverages to control blood glucose levels and body weight gain. The consumption of NNS has increased in recent years over the world, and many researches have indicated long-term sucralose administration altered the gut microbiome composition of mice. These studies all focus on the US Food and Drug Administration (FDA) defined acceptable daily intake (ADI), approximately 5 mg/kg BW/day for human. In our study, mice were given with T1-4 (0.0003, 0.003, 0.03, and 0.3 mg/mL) of sucralose, respectively, Control group mice were given normal water. In particular, 0.3 mg/mL of sucralose was equal to the ADI (5 mg/kg BW/day). After 16 weeks, all mice were weighted and sacrificed, the liver of each mouse was isolated and weighed, segments of jejunum, ileum and colon were collected for H&E-stained. The contents of jejunum, ileum, cecum and colon were collected for 16S rRNA gene sequencing. The results showed sucralose administration affects the intestinal barrier function evidenced by distinct lymphocyte aggregation in ileum and colon while not change the mice body weight. The 16S rRNA gene sequencing of the mice gut microbiome suggested sucralose administration significantly changed the composition of gut microbiota, especially in T1 and T4 group. For example, a reduction of probiotics abundance (Lachnoclostridium and Lachnospiraceae) was found in cecum of T4 group mice compared with Control group. On the other hand, Allobaculum, which was reported positively correlated with diabetes, was increased in the T1 and T4 group. In addition, the potential pathogens, including Tenacibaculum, Ruegeria, Staphylococcus were also increased in jejunum, ileum and colon by sucralose administration in T1 and T4 group. These new findings indicate that low dose of sucralose (T1) alter gut microbiome in mice, and these adverse health effects are equal to ADI level (T4). Overall, our study provides guidance and suggestions for the use of sucralose in foods and beverages.

Ten-Week Sucralose Consumption Induces Gut Dysbiosis and Altered Glucose and Insulin Levels in Healthy Young Adults

Sucralose consumption alters microbiome and carbohydrate metabolism in mouse models. However, there are no conclusive studies in humans. Our goals were to examine the effect of sucralose consumption on the intestinal abundance of bacterial species belonging to Actinobacteria, Bacteroidetes, and Firmicutes and explore potential associations between microbiome profiles and glucose and insulin blood levels in healthy young adults. In this open-label clinical trial, volunteers randomly drank water, as a control (n = 20), or 48 mg sucralose (n = 20), every day for ten weeks. At the beginning and the end of the study, participants were subjected to an oral glucose tolerance test (OGTT) to measure serum glucose and insulin every 15 min for 3 h and provided fecal samples to assess gut microbiota using a quantitative polymerase chain reaction. Sucralose intake altered the abundance of Firmicutes without affecting Actinobacteria or Bacteroidetes. Two-way ANOVA revealed that volunteers drinking sucralose for ten weeks showed a 3-fold increase in Blautia coccoides and a 0.66-fold decrease in Lactobacillus acidophilus compared to the controls. Sucralose consumption increased serum insulin and the area under the glucose curve compared to water. Long-term sucralose ingestion induces gut dysbiosis associated with altered insulin and glucose levels during an OGTT.

Food Additives, a Key Environmental Factor in the Development of IBD through Gut Dysbiosis

Diet is a key environmental factor in inflammatory bowel disease (IBD) and, at the same time, represents one of the most promising therapies for IBD. Our daily diet often contains food additives present in numerous processed foods and even in dietary supplements. Recently, researchers and national authorities have been paying much attention to their toxicity and effects on gut microbiota and health. This review aims to gather the latest data focusing on the potential role of food additives in the pathogenesis of IBDs through gut microbiota modulation. Some artificial emulsifiers and sweeteners can induce the dysbiosis associated with an alteration of the intestinal barrier, an activation of chronic inflammation, and abnormal immune response accelerating the onset of IBD. Even if most of these results are retrieved from in vivo and in vitro studies, many artificial food additives can represent a potential hidden driver of gut chronic inflammation through gut microbiota alterations, especially in a population with IBD predisposition. In this context, pending the confirmation of these results by large human studies, it would be advisable that IBD patients avoid the consumption of processed food containing artificial food additives and follow a personalized nutritional therapy prescribed by a clinical nutritionist.

Total and Free Sugar Levels and Main Types of Sugars Used in 18,784 Local and Imported Pre-Packaged Foods and Beverages Sold in Hong Kong

There is limited information regarding the free sugar content of pre-packaged foods in Hong Kong. This study aims to assess the free sugar content and identify the most frequently used free sugar ingredients (FSI) in pre-packaged foods in Hong Kong. Data from 18,784 products from the 2019 FoodSwitch Hong Kong database were used in this analysis. Ingredient lists were screened to identify FSI. Total sugar content was derived from nutrition labels on packaging. Free sugar content was estimated based on adaptation of a previously established systematic methodology. Descriptive statistics of the total sugar and free sugar content, as well as the mean ± SD contribution of free sugar to total sugar of the audited products were calculated, stratified by food groups. Almost two-thirds (64.5%) of the pre-packaged foods contained at least one FSI. 'Sugar (sucrose)' was the most popular FSI that was found in more than half (54.7%) of the products. 'Fruit and vegetable juices' (median 10.0; IQR 8.3-11.5 g/100 mL) were found to have a higher median free sugar content than 'Soft drinks' (8.0; 6.0-10.6 g/100 mL). Mean ± SD contribution of free sugar to the total sugar content was 65.8 ± 43.4%, with 8 out of 14 food groups having >70% total sugar as free sugar. To conclude, free sugar, especially sucrose, was extensively used in a wide variety of pre-packaged products sold in Hong Kong. Further studies are needed to assess the population intake of free sugar in Hong Kong to inform public health policy on free sugar reduction.

Holistic perspective of the role of gut microbes in diabetes mellitus and its management

The gut microbiota (GM) plays a role in the development and progression of type 1 and type 2 diabetes mellitus (DM) and its complications. Gut dysbiosis contributes to the pathogenesis of DM. The GM has been shown to influence the efficacy of different antidiabetic medications. Intake of gut biotics, like prebiotics, probiotics and synbiotics, can improve the glucose control as well as the metabolic profile associated with DM. There is some preliminary evidence that it might even help with the cardiovascular, ophthalmic, nervous, and renal complications of DM and even contribute to the prevention of DM. More large-scale research studies are needed before wide spread use of gut biotics in clinical practice as an adjuvant therapy to the current management of DM.

Development of tropical mixed juice with low added-sugar content: Sensory and nutritional aspects

The aim of the present study was to develop a mixed tropical fruit juice of cashew apple, acerola and melon with low added-sugar content considering sensory and nutritional aspects. Five formulations were developed varying the concentration of the different fruits. A total of 172 consumers rated their overall liking using a 9-point hedonic scale and described their sensory characteristics using a Check-all-that-apply question. In addition, the functional properties of the juices were evaluated by analyzing vitamin C, total phenolic compounds and antioxidant capacity. Results showed that the addition of sugar and fruit composition affected the sensory characteristics and consumer liking of the formulations. Samples without added sugar and with higher melon concentration showed lower liking scores (p < 0.05). In addition, the highest concentration of acerola had a positive effect on nutritional characteristics. The formulation with 50% of fruit pulp (60% of cashew apple, 30% of acerola and 10% of melon), 47% of water, and 3% of added sugar achieved the best results. The effect of aroma on sweetness perception was investigated by adding identical to natural aromas of melon, apple and pineapple to the selected formulation. However, aroma did not significantly modify sweetness perception, evaluated using a rate-all-that-apply question.

An Overview of Current Knowledge of the Gut Microbiota and Low-Calorie Sweeteners

This review provides an overview of the interrelationships among the diet, gut microbiota and health status, and then focuses specifically on published research assessing the relationship of low/no-calorie sweeteners (LNCS) to selected aspects of the gut microbiota. Microbiome research is expanding as new data on its role in health and disease vulnerability emerge. The gut microbiome affects health, digestion, and susceptibility to disease. In the last 10 years, investigations of LNCS effects on the gut microbiota have proliferated, though results are conflicting and are often confounded by differences in study design such as study diet, the form of the test article, dosage, and study population. Staying current on microbiome research and the role of dietary inputs, like LNCS, will allow healthcare and nutrition practitioners to provide evidenced-based guidance to the individuals they serve.

Diet Sugar-Free Carbonated Soda Beverage, Non-Caloric Flavors Consumption, and Diabetic Retinopathy: Any Linkage

PURPOSE

Assessing diabetic retinopathy (DR) risk factors and daily nutrition habits are vital for prevention. This study aims to evaluate the relationship between diet soda cans, non-nutritive sweetener consumption, and diabetic retinopathy.

PATIENTS AND METHODS

A cross-sectional study was conducted among 200 patients attending a diabetes center in Tabuk City, Saudi Arabia, from September 2019 to July 2020. A structured questionnaire was used to collect patients' demographic factors, and DR risk factors including the use of diet soda, non-nutritive sweeteners, and exercise habits. Dilated fundus eye examination was done to detect any diabetic retinopathy. A blood sample was taken for measuring glycated hemoglobin to assess the degree of glycemic control.

RESULTS

The participant's age was 50.74 ±13.51 years, and the duration since the diagnosis of diabetes was 9.99 ±6.97 years, body mass index was 27.28 ±4.68, and HbA1c %, 8.50 ±1.61), the patients used to consume 1.31 ±1.57 diet soda cans/week, and 1.06±1.39 artificial sweeteners/sachet/day. DR was found in 33%. Diet sugar-free carbonated soda beverage was associated with poor glycemic control and retinopathy, while non-caloric flavor consumption was associated with obesity (P-value<0.05). No association was evident regarding other factors (P-value>0.05).

CONCLUSION

Diet sugar-free carbonated soda beverage was associated with higher HbA1c and retinopathy, while non-caloric flavor consumption was associated with obesity. No association was evident regarding other factors. Further larger multicenter studies are needed.

A rational review on the effects of sweeteners and sweetness enhancers on appetite, food reward and metabolic/adiposity outcomes in adults

Numerous strategies have been investigated to overcome the excessive weight gain that accompanies a chronic positive energy balance. Most approaches focus on a reduction of energy intake and the improvement of lifestyle habits. The use of high intensity artificial sweeteners, also known as non-caloric sweeteners (NCS), as sugar substitutes in foods and beverages, is rapidly developing. NCS are commonly defined as molecules with a sweetness profile of 30 times higher or more that of sucrose, scarcely contributing to the individual's net energy intake as they are hardly metabolized. The purpose of this review is first, to assess the impact of NCS on eating behaviour, including subjective appetite, food intake, food reward and sensory stimulation; and secondly, to assess the metabolic impact of NCS on body weight regulation, glucose homeostasis and gut health. The evidence reviewed suggests that while some sweeteners have the potential to increase subjective appetite, these effects do not translate in changes in food intake. This is supported by a large body of empirical evidence advocating that the use of NCS facilitates weight management when used alongside other weight management strategies. On the other hand, although NCS are very unlikely to impair insulin metabolism and glycaemic control, some studies suggest that NCS could have putatively undesirable effects, through various indirect mechanisms, on body weight, glycemia, adipogenesis and the gut microbiota; however there is insufficient evidence to determine the degree of such effects. Overall, the available data suggests that NCS can be used to facilitate a reduction in dietary energy content without significant negative effects on food intake behaviour or body metabolism, which would support their potential role in the prevention of obesity as a complementary strategy to other weight management approaches. More research is needed to determine the impact of NCS on metabolic health, in particular gut microbiota.