Non-Nutritive Sweeteners and Their Implications on the Development of Metabolic Syndrome.
Plain language summary
Artificial sweeteners, such as aspartame, neotame, saccharin, sucralose, and stevia are widely promoted as low-calorie alternatives to sugar and are known as non-nutritive sweeteners (NNS). Generally, they have been considered as a healthy option to replace sugars, but data is emerging that they may influence obesity and metabolic syndrome (METs) and contribute to the development of type II diabetes. These non-nutritive sweeteners can be thousands of times sweeter than sugar and have been widely adopted by the food industry to help reduce calories, and promote weight loss and diabetic products. It is believed that 25% of children and 41% of adults consume low-calorie sweeteners regularly, with the beverage industry relying heavily on them. However, it is now been shown that these sweeteners can cause imbalances to gut bacteria and interact with taste receptors and insulin signalling. These findings mean that artificial sweeteners may trigger the same hormonal response as sugar by releasing insulin and overtime lead to insulin resistance, obesity, and overall metabolic syndrome. Finally, there is evidence that our body develops a learned response to sweeteners which paradoxically leads to weight gain.
Individuals widely use non-nutritive sweeteners (NNS) in attempts to lower their overall daily caloric intake, lose weight, and sustain a healthy diet. There are insufficient scientific data that support the safety of consuming NNS. However, recent studies have suggested that NNS consumption can induce gut microbiota dysbiosis and promote glucose intolerance in healthy individuals that may result in the development of type 2 diabetes mellitus (T2DM). This sequence of events may result in changes in the gut microbiota composition through microRNA (miRNA)-mediated changes. The mechanism(s) by which miRNAs alter gene expression of different bacterial species provides a link between the consumption of NNS and the development of metabolic changes. Another potential mechanism that connects NNS to metabolic changes is the molecular crosstalk between the insulin receptor (IR) and G protein-coupled receptors (GPCRs). Here, we aim to highlight the role of NNS in obesity and discuss IR-GPCR crosstalk and miRNA-mediated changes, in the manipulation of the gut microbiota composition and T2DM pathogenesis.
Impact of Fecal Microbiota Transplantation on Obesity and Metabolic Syndrome-A Systematic Review.
Plain language summary
Fecal microbiota transplantation (FMT) is a relatively new field of scientific exploration where patients receive faeces from a healthy donor to help repopulate their intestinal tract with healthful bacteria. The gut microbiome is an ecosystem of an estimated 10~100 trillion microorganisms and there is increasing research on the important role these bacteria play in supporting our health and weight. This study reviews all trials involving faecal transports in patients with either clinical obesity or Metabolic syndrome to see if it helped improve weight, bmi or other metabolic parameters. Three studies with 76 male patients were included in this review and the results showed that FMT recipients had improved insulin sensitivity and reduced HbA1c glucose levels after 6 weeks, but these improvements were short-term only. There were no differences in bmi, cholesterol, markers and fasting glucose levels. The conclusion is that whilst FMT may confer benefits there is still much to understand about the fecal microbial preparation, dosing, and method of delivery, as well as the host patient’s response.
undefined: Fecal microbiota transplantation (FMT) is a gut microbial-modulation strategy that has been investigated for the treatment of a variety of human diseases, including obesity-associated metabolic disorders. This study appraises current literature and provides an overview of the effectiveness and limitations of FMT as a potential therapeutic strategy for obesity and metabolic syndrome (MS). Five electronic databases and two gray literature sources were searched up to 10 December 2018. All interventional and observational studies that contained information on the relevant population (adult patients with obesity and MS), intervention (receiving allogeneic FMT) and outcomes (metabolic parameters) were eligible. From 1096 unique citations, three randomized placebo-controlled studies (76 patients with obesity and MS, body mass index = 34.8 ± 4.1 kg/m , fasting plasma glucose = 5.8 ± 0.7 mmol/L) were included for review. Studies reported mixed results with regards to improvement in metabolic parameters. Two studies reported improved peripheral insulin sensitivity (rate of glucose disappearance, RD) at 6 weeks in patients receiving donor FMT versus patients receiving the placebo control. In addition, one study observed lower HbA1c levels in FMT patients at 6 weeks. No differences in fasting plasma glucose, hepatic insulin sensitivity, body mass index (BMI), or cholesterol markers were observed between two groups across all included studies. While promising, the influence of FMT on long-term clinical endpoints needs to be further explored. Future studies are also required to better understand the mechanisms through which changes in gut microbial ecology and engraftment of microbiota affect metabolic outcomes for patients with obesity and MS. In addition, further research is needed to better define the optimal fecal microbial preparation, dosing, and method of delivery.
Sugar-Sweetened Beverage Consumption in Relation to Obesity and Metabolic Syndrome among Korean Adults: A Cross-Sectional Study from the 2012⁻2016 Korean National Health and Nutrition Examination Survey (KNHANES).
Plain language summary
Obesity and Metabolic Syndrome (MetS) in Korea has increased significantly in the last decade and dietary factors, including the consumption of sugar sweetened drinks, is considered one of the key drivers. Soft drinks, soda coffee, fruit juices, sports drinks and sweetened rice drinks are popular beverages in Asia. Consumption of these is a major source of sugar intake for the Korean population. This study analysed data from over 12,112 participants of the Korean National Health and Nutrition Examination Survey (KNHANES) to see if the consumption of sugar sweetened beverages was causally linked to obesity and MetS. Food questionnaires were used in the original study to assess which foods and drinks the participants consumed during a 1-year period. Within the study group the number of participants with obesity was 34.9% and MetS was 26.7% respectively. They found that the participants who regularly consumed >4 sugar sweetened beverages per week consumed more calories on average than those who did not drink these beverages. In men, it was linked to higher blood pressure and blood glucose levels whilst in women it linked to a higher body mass index (BMI), increased waist circumference, and elevated cholesterol. Overall drinking 1 sugar sweetened beverage per day increased the risks of obesity in women by 59% and MetS by 61% whilst in men it increased the prevalence of obesity by 41% and MetS by 7%. Therefore drinking sugar sweetened beverages increases the risk of both obesity and MetS.
undefined: It is well known that the consumption of sugar-sweetened beverages (SSBs) increases the risk of developing obesity and metabolic syndrome (MetS). However, there are not many studies investigating the link between SSBs and increased incidences of diseases in the Asian population, and in particular, in Korea. We explored the association of SSB consumption with the risk of developing obesity and MetS among Korean adults (12,112 participants from the 2012⁻2016 Korean National Health and Nutrition Examination Survey). We calculated the total SSB consumption frequency by counting each beverage item, including soda beverages, fruit juices, and sweetened rice drinks. Obesity was defined as a body mass index ≥25 kg/m², and MetS was defined using the National Cholesterol Education Program, Adult Treatment Panel III. A survey logistic regression analyses was conducted to examine the association of SSB consumption with obesity and MetS, adjusting for related confounders such as age, energy intake, household income, education, alcohol drinking, smoking status, and physical activity. The SSB consumption was positively associated with an increased risk of the prevalence for obesity (Odd ratio (OR): 1.60; 95% confidence interval (CI): 1.23⁻2.09; for trend = 0.0009) and MetS (OR: 1.61; 95% CI: 1.20⁻2.16; for trend = 0.0003) among women. In men, SSB consumption only contributed to a higher prevalence of obesity (OR: 1.38; 95% CI: 1.11⁻1.72; for trend = 0.0041). In conclusion, increased consumption of SSBs was closely linked with a higher prevalence of obesity and MetS in the Korean population.
Effects of weight loss interventions for adults who are obese on mortality, cardiovascular disease, and cancer: systematic review and meta-analysis.
BMJ (Clinical research ed.). 2017;359:j4849
Plain language summary
Obesity is known to increase the risk of many diseases including cardiovascular disease, various cancers and type 2 diabetes. Interestingly, there is evidence suggesting weight loss in obese adults may be harmful, particularly in older people with cardiovascular disease. The aim of this systematic review was to assess the effect of weight loss interventions for adults with obesity on mortality, cardiovascular disease, cancer and body weight. Based on the 30,000 participants identified, current evidence shows that weight loss interventions significantly decrease all cause mortality. There was also evidence to suggest weight loss is associated with developing new cardiovascular events, though fewer trials reported these outcomes so uncertainty remains around these results. Based on the current literature and this review, the authors conclude weight-reducing diets may reduce all cause mortality in adults with obesity and support public health measures to prevent weight gain and facilitate weight loss.
undefined: To assess whether weight loss interventions for adults with obesity affect all cause, cardiovascular, and cancer mortality, cardiovascular disease, cancer, and body weight. Systematic review and meta-analysis of randomised controlled trials (RCTs) using random effects, estimating risk ratios, and mean differences. Heterogeneity investigated using Cochran's Q and I statistics. Quality of evidence assessed by GRADE criteria. Medline, Embase, the Cochrane Central Register of Controlled Trials, and full texts in our trials' registry for data not evident in databases. Authors were contacted for unpublished data. RCTs of dietary interventions targeting weight loss, with or without exercise advice or programmes, for adults with obesity and follow-up ≥1 year. 54 RCTs with 30 206 participants were identified. All but one trial evaluated low fat, weight reducing diets. For the primary outcome, high quality evidence showed that weight loss interventions decrease all cause mortality (34 trials, 685 events; risk ratio 0.82, 95% confidence interval 0.71 to 0.95), with six fewer deaths per 1000 participants (95% confidence interval two to 10). For other primary outcomes moderate quality evidence showed an effect on cardiovascular mortality (eight trials, 134 events; risk ratio 0.93, 95% confidence interval 0.67 to 1.31), and very low quality evidence showed an effect on cancer mortality (eight trials, 34 events; risk ratio 0.58, 95% confidence interval 0.30 to 1.11). Twenty four trials (15 176 participants) reported high quality evidence on participants developing new cardiovascular events (1043 events; risk ratio 0.93, 95% confidence interval 0.83 to 1.04). Nineteen trials (6330 participants) provided very low quality evidence on participants developing new cancers (103 events; risk ratio 0.92, 95% confidence interval 0.63 to 1.36). Weight reducing diets, usually low in fat and saturated fat, with or without exercise advice or programmes, may reduce premature all cause mortality in adults with obesity. PROSPERO CRD42016033217.
Effect of probiotics on lipid profiles and blood pressure in patients with type 2 diabetes: A meta-analysis of RCTs.
Plain language summary
Type 2 diabetes mellitus (T2DM) is the most common metabolic disorder worldwide. Though many clinical studies have explored the effects of probiotics on T2DM they have concluded mixed results. The purpose of this meta-analysis was to evaluate all current randomised controlled trials and determine the effect of probiotics on lipid profiles and blood pressure in patients with T2DM. According to the existing literature, probiotic supplementation for patients with T2DM has a positive effect by lowering total cholesterol and increasing high-density lipoproteins (HDLs). While these beneficial effects on lipid profiles and blood pressure have been found, the authors conclude there is still a need for a multi-centre, longitudinal study to better understand the effects of probiotics on patients with T2DM.
BACKGROUND This meta-analysis aimed to systematically evaluate the effects of probiotics on blood lipid and blood pressure among patients with type 2 diabetes mellitus (T2DM) based on the randomized controlled studies. METHODS PubMed, Cochrane, Embase, Wanfang, China National Knowledge Infrastructure, and VIP database were searched by the index words to identify the qualified randomized control trial. The latest research was done in the January 2017. Mean difference (MD) along with 95% confidence interval (CI) was used to analyze the included outcomes. RESULTS Ten trials were included at last with 297 patients in the treatment group and 294 patients in the control group. Probiotics significantly decreased the value of total cholesterol (SMD -0.57, 95% CI -0.92 to 0.21), triglyceride (SMD -0.66, 95% CI -0.93 to 0.39), low-density lipoprotein (SMD -0.40, 95% CI -0.79 to 0.01), systolic blood pressure (WMD -5.04, 95% CI -8.8 to 1.20), diastolic blood pressure (SMD -0.39, 95% CI -0.62 to 0.17), fasting blood glucose (FBG) (SMD 3.54, 95% CI 1.94-5.15) compared with the placebo treatment. Apart from this, probiotics could significantly improve the value of high-density lipoprotein (SMD 0.38, 95% CI 0.03-0.73). CONCLUSION Probiotics may decrease the indexes of lipid profile, blood pressure, and FBG in patients with T2DM; application of probiotics might be a new method for lipid profiles and blood pressure management in T2DM.