scholarly journals The Effects of Almonds on Gut Microbiota, Glycometabolism, and Inflammatory Markers in Patients with Type 2 Diabetes: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

Nutrients ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 3377
Author(s):  
Omorogieva Ojo ◽  
Xiao-Hua Wang ◽  
Osarhumwese Osaretin Ojo ◽  
Amanda Rodrigues Amorim Adegboye

The use of nutritional interventions for managing diabetes is one of the effective strategies aimed at reducing the global prevalence of the condition, which is on the rise. Almonds are the most consumed tree nut and they are known to be rich sources of protein, monounsaturated fatty acids, essential minerals, and dietary fibre. Therefore, the aim of this review was to evaluate the effects of almonds on gut microbiota, glycometabolism, and inflammatory parameters in patients with type 2 diabetes. Methods: This systematic review and meta-analysis was carried out according to the preferred reporting items for systematic review and meta-analysis (PRISMA). EBSCOhost, which encompasses the Health Sciences Research Databases; Google Scholar; EMBASE; and the reference lists of articles were searched based on population, intervention, control, outcome, and study (PICOS) framework. Searches were carried out from database inception until 1 August 2021 based on medical subject headings (MesH) and synonyms. The meta-analysis was carried out with the Review Manager (RevMan) 5.3 software. Results: Nine randomised studies were included in the systematic review and eight were used for the meta-analysis. The results would suggest that almond-based diets have significant effects in promoting the growth of short-chain fatty acid (SCFA)-producing gut microbiota. Furthermore, the meta-analysis showed that almond-based diets were effective in significantly lowering (p < 0.05) glycated haemoglobin (HbA1c) levels and body mass index (BMI) in patients with type 2 diabetes. However, it was also found that the effects of almonds were not significant (p > 0.05) in relation to fasting blood glucose, 2 h postprandial blood glucose, inflammatory markers (C-reactive protein and Tumour necrosis factor α, TNF-α), glucagon-like peptide-1 (GLP-1), homeostatic model assessment of insulin resistance (HOMA–IR), and fasting insulin. The biological mechanisms responsible for the outcomes observed in this review in relation to reduction in HbA1c and BMI may be based on the nutrient composition of almonds and the biological effects, including the high fibre content and the low glycaemic index profile. Conclusion: The findings of this systematic review and meta-analysis have shown that almond-based diets may be effective in promoting short-chain fatty acid-producing bacteria and lowering glycated haemoglobin and body mass index in patients with type 2 diabetes compared with control. However, the effects of almonds were not significant (p > 0.05) with respect to fasting blood glucose, 2 h postprandial blood glucose, inflammatory markers (C-reactive protein and TNF-α), GLP-1, HOMA–IR, and fasting insulin.

Nutrients ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1905 ◽  
Author(s):  
Omorogieva Ojo ◽  
Sharon Marie Weldon ◽  
Trevor Thompson ◽  
Rachel Crockett ◽  
Xiao-Hua Wang

Background: The prevalence of diabetes is on the increase in the UK and worldwide, partly due to unhealthy lifestyles, including poor dietary regimes. Patients with diabetes and other co-morbidities such as stroke, which may affect swallowing ability and lead to malnutrition, could benefit from enteral nutrition, including the standard formula (SF) and diabetes-specific formulas (DSF). However, enteral nutrition presents its challenges due to its effect on glycaemic control and lipid profile. Aim: The aim of this review was to evaluate the effectiveness of diabetes-specific enteral nutrition formula versus SF in managing cardiometabolic parameters in patients with type 2 diabetes. Method: This review was conducted in accordance with the preferred reporting items for systematic reviews and meta-analyses. Three databases (Pubmed, EMBASE, PSYCInfo) and Google scholar were searched for relevant articles from inception to 2 January 2019 based on Population, Intervention, Comparator, Outcomes and Study designs (PICOS) framework. Key words, Medical Subject Heading (MeSH) terms, and Boolean operators (AND/OR) formed part of the search strategy. Articles were evaluated for quality and risks of bias. Results: Fourteen articles were included in the systematic review and five articles were selected for the meta-analysis. Based on the findings of the review and meta-analysis, two distinct areas were evident: the effect of DSF on blood glucose parameters and the effect of DSF on lipid profile. All fourteen studies included in the systematic review showed that DSF was effective in lowering blood glucose parameters in patients with type 2 diabetes compared with SF. The results of the meta-analysis confirmed the findings of the systematic review with respect to the fasting blood glucose, which was significantly lower (p = 0.01) in the DSF group compared to SF, with a mean difference of −1.15 (95% CI −2.07, −0.23) and glycated haemoglobin, which was significantly lower (p = 0.005) in the DSF group compared to the SF group following meta-analysis and sensitivity analysis. However, in relation to the sensitivity analysis for the fasting blood glucose, differences were not significant between the two groups when some of the studies were removed. Based on the systematic review, the outcomes of the studies selected to evaluate the effect of DSF on lipid profile were variable. Following the meta-analysis, no significant differences (p > 0.05) were found between the DSF and SF groups with respect to total cholesterol, LDL cholesterol and triglyceride. The level of the HDL cholesterol was significantly higher (p = 0.04) in the DSF group compared to the SF group after the intervention, with a mean difference of 0.09 (95% CI, 0.00, 0.18), although this was not consistent based on the sensitivity analysis. The presence of low glycaemic index (GI) carbohydrate, the lower amount of carbohydrate and the higher protein, the presence of mono-unsaturated fatty acids and the different amounts and types of fibre in the DSF compared with SF may be responsible for the observed differences in cardiometabolic parameters in both groups. Conclusion: The results provide evidence to suggest that DSF is effective in controlling fasting blood glucose and glycated haemoglobin and in increasing HDL cholesterol, but has no significant effect on other lipid parameters. However, our confidence in these findings would be increased by additional data from further studies.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Ruo-Lan Li ◽  
Tai-Wei Dong ◽  
Ji-Gang Wei ◽  
Feng Gao ◽  
Min Li ◽  
...  

Objective. To systematically evaluate the effectiveness of Shenqi Jiangtang granule (SQJT) in the treatment of type 2 diabetes. Methods. We searched CNKI, Wanfang Data, VIP, and PubMed databases to collect randomized controlled trials (RCT) of Shenqi Jiangtang granules in the treatment of type 2 diabetes. The search time was from January 2014 to the present. Data were extracted, and quality was evaluated. Metadata analysis of the extracted data was carried out using RevMa5.2 software. The final results are expressed in relative risk (RR), mean difference (MD), and 95% CI. Results. This study included a total of 13 studies, 1160 subjects. Meta-analysis results showed that the test group was better than the control group (RR = 1.26, 95% CI 1.18–1.34, P < 0.00001 ). The fasting blood glucose, postprandial blood glucose, and glycated hemoglobin of the test group were also significantly better than those of the control group. Conclusion. Shenqi Jiangtang granules have a certain clinical effect and low adverse reaction rate for the treatment or adjuvant treatment of type 2 diabetes. At present, the drug has been widely used in clinical practice, but a large number of large-sample clinical trials are needed to further verify its specific efficacy and safety.


Author(s):  
Omorogieva Ojo ◽  
Xiao-Hua Wang ◽  
Osarhumwese Ojo ◽  
Jude Ibe

Background: People who abuse substances are at increased risk of metabolic syndrome and diabetes resulting partly from increased cell damage and due to the effects of opioids on glucose homeostasis. Therefore, people with diabetes who abuse substances may carry greater health risks than the general population resulting from their effect on glucose metabolism. These substances may be in the form of cannabis, hallucinogens, opioids, and stimulants. Therefore, the aim of this review was to evaluate the effects of substance abuse on blood glucose parameters in patients with diabetes. Method: Databases including Embase, Psycho-Info, Google Scholar and PubMed were searched systematically for relevant articles from database inception to May 2018. Search terms including medical subject headings (MeSH) based on the Population, Intervention, Comparator and Outcomes (PICO) framework was used to access the databases. Eligible articles were selected based on set inclusion and exclusion criteria. The articles reviewed were evaluated for quality and meta-analysis and sensitivity analysis were carried out using the Review Manager (RevMan 5.3, The Cochrane Collaboration, Copenhagen, Denmark). The Random effects model was used for the data analysis. Results: Twelve studies which met the inclusion criteria were included in the systematic review, while nine articles were selected for the meta-analysis. The results of the meta-analysis showed that substance abuse does not have significant effects (p > 0.05) on postprandial blood glucose and glycated haemoglobin in patients with diabetes. With respect to the effect of substance abuse on fasting blood glucose, while this was significant (p < 0.05) following meta-analysis, the results of the sensitivity test did not demonstrate any significant difference (p > 0.05) between patients who abused substances compared with control. This would suggest that the effect of substance abuse on fasting blood glucose in these patients was not very reliable or not consistent. Conclusions: The effect of substance abuse on glycated haemoglobin and postprandial blood glucose in patients with diabetes was not significant. In the meta-analysis, while the value was slightly lower with respect to postprandial blood glucose, this was slightly higher in relation to HbA1c in the substance abuse group compared with control. On the other hand, the effect of substance abuse on fasting blood glucose was significant (p = 0.03) compared with control, but this was attenuated following a sensitivity test. A range of factors including eating habits, characteristics of drugs, erratic lifestyle of patients may explain the outcome of this review. There is the need for randomised controlled trials that will include diet and medication history in order to fully understand the effect of substance abuse on blood glucose parameters in patients with diabetes.


Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1805
Author(s):  
Omorogieva Ojo ◽  
Osarhumwese Osaretin Ojo ◽  
Nazanin Zand ◽  
Xiaohua Wang

Background: A disequilibrium of the gut microbial community has been closely associated with systemic inflammation and metabolic syndromes including type 2 diabetes. While low fibre and high fat diets may lead to dysbiosis of the gut microbiome as a result of the loss of useful microbes, it has been reported that a high fibre diet may prevent the fermentation of protein and may promote eubiosis of gut microbiota. Aim: This review aims to evaluate the effect of dietary fibre (DF) on gut microbiota, lipid profile, and inflammatory markers in patients with type 2 diabetes. Methods: The PRISMA framework was relied on to conduct this systematic review and meta-analysis. Searches were carried out using electronic databases and reference list of articles. Results: Eleven studies were included in the systematic review, while ten studies were included in the meta-analysis. The findings revealed five distinct areas including the effects of DF on (a) gut microbiota (122 participants); (b) lipopolysaccharides (LPS, 79 participants) and lipopolysaccharides binding protein (LBP, 81 participants); (c) lipid profile; (d) inflammatory markers; and (e) body mass index (BMI, 319 participants). The relative abundance of Bifidobacterium increased by 0.73 (95% CI: 0.57, 0.89) in the DF group in contrast to the control (p < 0.05). With respect to LPS, the level was lower in the DF group than the control and the difference was significant (p < 0.05). The standardised mean difference for LPS was −0.45 (95% CI: −0.90, −0.01) although the difference between the two groups in relation to LBP was not significant (p = 0.08) and the mean difference was 0.92 (95% CI: −0.12, 1.95). While there was a decrease of −1.05 (95% CI: −2.07, −0.02) with respect to total cholesterol (356 participants) in the DF group as compared with the control (p < 0.05), both groups were not significantly different (p > 0.05) in the other lipid parameters. The difference between the groups was significant (p < 0.05) in relation to C-reactive protein, and the mean difference was 0.43 (95% CI: 0.02, 0.84). This could be due to the short duration of the included studies and differences in participants’ diets including the amount of dietary fibre supplements. However, the groups were not significantly different (p > 0.05) with respect to the other inflammatory markers. The meta-analysis of the BMI showed that the DF group decreased by −0.57 (95% CI: −1.02, −0.12) as compared with the control and this was significant (p < 0.01). Conclusion: DF significantly (p < 0.05) increased the relative abundance of Bifidobacterium and significantly decreased (p < 0.05) LPS, total cholesterol, and BMI as compared with the control. However, DF did not seem to have an effect that was significant on LBP, triglyceride, HDL cholesterol, LDL cholesterol, IL-6, TNF-α, adiponectin, and leptin. These findings have implications for public health in relation to the use of dietary fibre in nutritional interventions and as strategies for managing type 2 diabetes.


Proceedings ◽  
2020 ◽  
Vol 61 (1) ◽  
pp. 28
Author(s):  
Omorogieva Ojo ◽  
Qianqian Feng ◽  
Osarhumwese Osaretin Ojo ◽  
Xiaohua Wang

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.


2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Ding Meng ◽  
Wang Chunyan ◽  
Dong Xiaosheng ◽  
Yi Xiangren

Objective. The purpose of this study was to investigate the effects of Qigong on type 2 diabetes mellitus (DM) using the systematic review and meta-analysis. Methods. All prospective, randomized, controlled clinical trials published in English or Chinese and involving the use of Qigong by patients with DM were searched in 7 electronic databases from their respective inception to June 2016. The meta-analysis was conducted using the Revman 5.2. The quality of the included trials was assessed using the Jadad rating scale. Two researchers independently completed the inclusion, data extraction, and quality assessment. Results. Twenty-one trials with 1326 patients met the inclusion criteria and were reviewed. The meta-analysis demonstrated that, compared with no exercise, the Qigong had significant effects on fasting blood glucose (MD = −0.99, 95% CI (−1.23, 0.75), P<0.0001), HbA1c (MD = −0.84, 95% CI (−1.02, −0.65), P<0.0001), and postprandial blood glucose (MD = −1.55, 95% CI (−2.19, −0.91), P<0.00001). Conclusion. The Qigong training can improve the blood glucose status of the type 2 DM patients and has positive effects on the management of type 2 DM. However, future research with better quality still needs to be conducted to address the effects of Qigong on type 2 DM.


Nutrients ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3239 ◽  
Author(s):  
Omorogieva Ojo ◽  
Qian-Qian Feng ◽  
Osarhumwese Osaretin Ojo ◽  
Xiao-Hua Wang

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.


2021 ◽  
Author(s):  
Zhiyang Wang ◽  
Carine Ronsmans ◽  
Benjamin Woolf

Background: Although previous studies suggested the protective effect of zinc for type-2 diabetes, the unitary causal effect remains inconclusive. Objective: We investigated the causal effect of zinc as a single intervention on glycemic control in type-2 diabetes patients, using a systematic review of RCTs and two-sample Mendelian randomization (MR). Methods: Four outcomes were identified: fasting blood glucose/fasting glucose, hemoglobin A1c (HbA1c), homeostasis model assessment of insulin resistance (HOMA-IR), and serum insulin/fasting insulin level. In the systematic review, four databases were searched up to June 2021. Results were synthesized through the random-effects meta-analysis. Single nucleotide polymorphisms (SNPs) that are independent and are strongly related to zinc supplements were selected from MR-base to perform the two-sample MR with inverse-variance weighted (IVW) coefficient. Results: In the systematic review, 14 trials were included. The zinc supplement led to a significant reduction in the post-trial mean of fasting blood glucose (mean difference (MD): -26.52, 95%CI: -35.13, -17.91), HbA1C (MD: -0.52, 95%CI: -0.90, -0.13), and HOMA-IR (MD: -1.65, 95%CI: -2.62, -0.68), compared to the control group. In the two-sample MR, zinc supplement with 2 SNPs associated with lower fasting glucose (IVW coefficient: -2.04, 95%CI: -3.26, -0.83), but not specified type-2 diabetes. Conclusion: Although the study was limited by the few trials (review) and SNPs (two-sample MR), we demonstrated that the single zinc supplementary improved glycemic control among type-2 diabetes patients with causal evidence to a certain extent.


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