Background: Alow carbohydrate diet (LCD) is more beneficial for the glycometabolism in type 2 diabetes (T2DM) and may be effective in reducing depression. Almond, which is a common nut, has been shown to effectively improve hyperglycemia and depression symptoms. This study aimed to determine the effect of an almond-based LCD (a-LCD) on depression and glycometabolism, as well as gut microbiota and fasting glucagon-like peptide 1 (GLP-1) in patients with T2DM. Methods: This was a randomized controlled trial which compared an a-LCD with a low-fat diet (LFD). Forty-five participants with T2DM at a diabetes club and the Endocrine Division of the First and Second Affiliated Hospital of Soochow University between December 2018 to December 2019 completed each dietary intervention for 3 months, including 22 in the a-LCD group and 23 in the LFD group. The indicators for depression and biochemical indicators including glycosylated hemoglobin (HbA1c), gut microbiota, and GLP-1 concentration were assessed at the baseline and third month and compared between the two groups. Results: A-LCD significantly improved depression and HbA1c (p < 0.01). Meanwhile, a-LCD significantly increased the short chain fatty acid (SCFAs)-producing bacteria Roseburia, Ruminococcus and Eubacterium. The GLP-1 concentration in the a-LCD group was higher than that in the LFD group (p < 0.05). Conclusions: A-LCD could exert a beneficial effect on depression and glycometabolism in patients with T2DM. We speculate that the role of a-LCD in improving depression in patients with T2DM may be associated with it stimulating the growth of SCFAs-producing bacteria, increasing SCFAs production and GPR43 activation, and further maintaining GLP-1 secretion. In future studies, the SCFAs and GPR43 activation should be further examined.

Background: The prevalence of type 2 diabetes is on the increase worldwide, and it represents about 90% of adults who are diagnosed with diabetes. Overweight and obesity, lifestyle, genetic predisposition and gut microbiota dysbiosis have been implicated as possible risk factors in the development of type 2 diabetes. In particular, low intake of dietary fibre and consumption of foods high in fat and sugar, which are common in western lifestyle, have been reported to contribute to the depletion of specific bacterial taxa. Therefore, it is possible that intake of high dietary fibre may alter the environment in the gut and provide the needed substrate for microbial bloom. Aim: The current review is a systematic review and meta-analysis which evaluated the role of dietary fibre in modulating gut microbiota dysbiosis in patients with type 2 diabetes. Methods: This is a systematic review and meta-analysis of randomised controlled trials which relied on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework. Electronic searches were conducted using EBSCOHost with links to Health Sciences Research Databases, EMBASE and Google Scholar. The reference lists of articles were also searched for relevant studies. Searches were conducted from date of commencement of the database to 5 August 2020. The search strategy was based on the Population, Intervention, Comparator, Outcomes, Studies (PICOS) framework and involved the use of synonyms and medical subject headings (MesH). Search terms were combined with Boolean operators (OR/AND). Results: Nine studies which met the inclusion criteria were selected for the systematic review and meta-analysis, and four distinct areas were identified: the effect of dietary fibre on gut microbiota; the role of dietary fibre on short-chain fatty acids (SCFAs); glycaemic control; and adverse events. There was significant difference (p < 0.01) in the relative abundance of Bifidobacterium with a mean difference of 0.72 (95% CI, 0.56, 0.89) between the dietary fibre group compared with placebo. In relation to the meta-analysis for SCFAs, while there was significant difference (p = 0.02) between the dietary fibre group and placebo with a standardised mean difference of 0.5 (95% CI, 0.08, 0.91) regarding total SCFAs, the differences were not significant (p > 0.05) in relation to acetic acid, propionic acid and butyric acid. There was only significant improvement (p = 0.002) with respect to glycated haemoglobin with a mean difference of −0.18 (95% CI, −0.29, −0.06) between the dietary fibre group and placebo group. Differences between the two groups were not significant (p > 0.05) in relation to fasting blood glucose and homeostatic model assessment of insulin resistance (HOMA-IR). Furthermore, there were no significant differences between the two groups in subjects who reported adverse events. It is possible that the promotion of SCFA producers in greater diversity and abundance by dietary fibre in this review led to improvement in glycated haemoglobin, partly due to increased glucagon-like peptide-1 (GLP-1) production. In addition, Bifidobacterium lactis has been reported to increase glycogen synthesis, decrease expression of hepatic gluconeogenesis genes, improve translocation of glucose transport-4 and promote glucose uptake. It is also possible that the reduction in body weight of participants in the intervention group compared with control may have contributed to the observed improvement in glycated haemoglobin. Conclusion: This systematic review and meta-analysis have demonstrated that dietary fibre can significantly improve (p < 0.05) the relative abundance of Bifidobacterium, total SCFAs and glycated haemoglobin. However, dietary fibre did not appear to have significant effect (p > 0.05) on fasting blood glucose, HOMA-IR, acetic acid, propionic acid, butyric acid and adverse events.

The impact of the COVID-19 lockdown on glycaemic control and other metabolic parameters in patients with type 2 diabetes is still evolving. Aim: This systematic review and meta-analysis aims to examine the effects of COVID-19 lockdown on glycaemic control and lipid profile in patients with type 2 diabetes. Methods: The PRISMA framework was the method used to conduct the systematic review and meta-analysis, and the search strategy was based on the population, intervention, control and outcome (PICO) model. The Health Sciences Research databases was accessed via EBSCO-host, and EMBASE were searched for relevant articles. Searches were conducted from inception of the databases until 17 September 2021. Results: The results identified three distinct areas: glycaemic control, lipid parameters and body mass index. It was found that COVID-19 lockdown led to a significant (p < 0.01) increase in the levels of glycated haemoglobin (%) compared with pre-COVID group (gp) with a mean difference of 0.34 (95% CI: 0.30, 0.38). Eleven studies contributed to the data for glycated haemoglobin analysis with a total of 16,895 participants (post-COVID-19 lockdown gp, n = 8417; pre-COVID gp, n = 8478). The meta-analysis of fasting plasma glucose (mg/dL) also showed a significant (p < 0.05) increase in levels of post-COVID-19 lockdown gp compared with pre-COVID gp, with a mean difference of 7.19 (95% CI: 5.28, 9.10). Six studies contributed to fasting plasma glucose analysis involving a total of 2327 participants (post-COVID-19 lockdown, n = 1159; pre-COVID gp, n = 1168). The body mass index (BMI) (kg/m²) analysis also demonstrated that post-COVID-19 lockdown gp had a significantly (p < 0.05) higher BMI than the pre-COVID gp with a mean difference of 1.13 (95% CI: 0.99; 1.28), involving six studies and a total of 2363 participants (post-COVID-19 lockdown gp, n = 1186; pre-COVID gp, n = 1177). There were significantly (p < 0.05) lower levels of total cholesterol (mmol/L), triglyceride (mmol/L) and LDL cholesterol (mmol/L), and higher levels of HDL cholesterol (mg/dL) in the post-COVID-19 lockdown gp compared with pre-COVID gp, although these results were not consistent following sensitivity analysis. Conclusion: The findings of the systematic review and meta-analysis have demonstrated that COVID-19 lockdown resulted in a significant increase (p < 0.05) in the levels of glycated haemoglobin, fasting glucose and body mass index in patients with type 2 diabetes. In contrast, the effect of the lockdown on lipid parameters, including total cholesterol, triglycerides, LDL and HDL cholesterol was not consistent.

Background: Patients who are critically ill with COVID-19 could have impaired nutrient absorption due to disruption of the normal intestinal mucosa. They are often in a state of high inflammation, increased stress and catabolism as well as a significant increase in energy and protein requirements. Therefore, timely enteral nutrition support and the provision of optimal nutrients are essential in preventing malnutrition in these patients. Aim: This review aims to evaluate the effects of enteral nutrition in critically ill patients with COVID-19. Method: This systematic review and meta-analysis was conducted based on the preferred reporting items for systematic review and meta-Analysis framework and PICO. Searches were conducted in databases, including EMBASE, Health Research databases and Google Scholar. Searches were conducted from database inception until 3 February 2022. The reference lists of articles were also searched for relevant articles. Results: Seven articles were included in the systematic review, and four articles were included in the meta-analysis. Two distinct areas were identified from the results of the systematic review and meta-analysis: the impact of enteral nutrition and gastrointestinal intolerance associated with enteral nutrition. The impact of enteral nutrition was further sub-divided into early enteral nutrition versus delayed enteral nutrition and enteral nutrition versus parenteral nutrition. The results of the meta-analysis of the effects of enteral nutrition in critically ill patients with COVID-19 showed that, overall, enteral nutrition was effective in significantly reducing the risk of mortality in these patients compared with the control with a risk ratio of 0.89 (95% CI, 0.79, 0.99, p = 0.04). Following sub-group analysis, the early enteral nutrition group also showed a significant reduction in the risk of mortality with a risk ratio of 0.89 (95% CI, 0.79, 1.00, p = 0.05). The Relative Risk Reduction (RRR) of mortality in patients with COVID-19 by early enteral nutrition was 11%. There was a significant reduction in the Sequential Organ Failure Assessment (SOFA) score in the early enteral nutrition group compared with the delayed enteral nutrition group. There was no significant difference between enteral nutrition and parenteral nutrition in relation to mortality (RR = 0.87; 95% CI, 0.59, 1.28, p = 0.48). Concerning the length of hospital stay, length of ICU stay and days on mechanical ventilation, while there were reductions in the number of days in the enteral nutrition group compared to the control (delayed enteral nutrition or parenteral nutrition), the differences were not significant (p > 0.05). Conclusion: The results showed that early enteral nutrition significantly (p < 0.05) reduced the risk of mortality among critically ill patients with COVID-19. However, early enteral nutrition or enteral nutrition did not significantly (p > 0.05) reduce the length of hospital stay, length of ICU stay and days on mechanical ventilation compared to delayed enteral nutrition or parenteral nutrition. More studies are needed to examine the effect of early enteral nutrition in patients with COVID-19.

Background: Diabetes prevalence is on the increase globally and its impact on those with the condition in terms of acute and chronic complications can be profound. People with type 2 diabetes constitute the majority of those with the condition and the risk factors include obesity, lifestyle and gut microbiota dysbiosis. Poor dietary intake has been reported to influence the community of the gut microbiome. Therefore, a higher intake of dietary fibre may alter the environment in the gut and promote microbial growth and proliferation. Aim: This is a systematic review and meta-analysis which examined the effect of dietary fibre on gut microbiota in patients with type 2 diabetes. Method: This review was conducted in line with the PRISMA framework. Databases were searched for relevant articles which were screened based on inclusion and exclusion criteria. Results: Nine articles which met the inclusion criteria were selected for the systematic review and meta-analysis. High dietary fibre intake significantly improved (p < 0.05) the abundance of Bifidobacterium, total short-chain fatty acids (SCFAs) and HbA1c. Discussion: The promotion of SCFA producers in terms of greater diversity and abundance by dietary fibre may have resulted in improvement in glycated haemoglobin, partly due to increased GLP–1 production. Conclusion: High consumption of dietary fibre has a significant (p < 0.05) effect on Bifidobacterium, total SCFAs and HbA1c, but not (p > 0.05) on propionic, butyric and acetic acid, fasting blood glucose and the homeostatic model assessment of insulin resistance HOMAR–IR.