Plant-based dietary index in relation to gut microbiota in Arab women.

Plant-based foods may influence gut microbiota profiles and contribute to overall human health. However, not all plant-based diets are nutritionally equivalent. We aimed to assess the association between a plant-based dietary index (PDI), specifically unhealthy PDI and healthy PDI (hPDI), and gut microbial composition and diversity in young women in Saudi Arabia. This observational study included 92 healthy women aged 18 to 25 years. Dietary and anthropometric data were collected. Fecal samples were analyzed using a novel whole-genome shotgun sequencing technique. Alpha and beta diversities measured the richness and composition of the gastrointestinal system. Relationships were examined with Pearson correlation, linear regression, and Wilcoxon Rank-Sum tests. Participants with higher PDI had higher levels of Bacteroides_u_s than those with lower PDI. hPDI was positively correlated with Bifidobacterium pseudocatenulatum, Bifidobacterium longum, Oscillibacter, and Lactobacillus acidophilus and inversely correlated with Clostridioides difficile (P < .05). Unhealthy plant-based dietary index was inversely correlated with B pseudocatenulatum, B longum, and L acidophilus and positively correlated with C difficile (P < .05) and other species of interest. In conclusion, hPDI scores were significantly associated with microbiota species linked with favorable health outcomes, independent of body mass index and gut microbial richness and composition in Arab women. Future studies should investigate the modulating effect of plant-based diets on the species identified in the current study.

Types of fiber and gut microbiota composition and diversity among arab females.

Objectives: Dietary fiber is recognized as an important nutrient for gut health. However, research on the relations of different types of fibers (soluble and insoluble) to the human microbiota health is limited. This study aimed to identify whether higher habitual intake of soluble and/or insoluble fiber have a different influence on the composition, diversity, and abundance of microbiota. Methods: We examined the fecal microbial composition of 92 healthy females aged 18 and above using the novel shotgun metagenomics sequencing technique. The habitual fiber intake was determined using the Saudi food frequency questionnaire. Pearson's correlation was used for the correlations between total, soluble, and insoluble fiber and gut microbiota. α- and ß-diversities were applied to acquire the distinctions in the relative abundances of bacterial taxa. Results: Our findings show that higher dietary fiber, particularly insoluble fiber, was significantly correlated with the abundances of Bacteroides_u_s, Bacteroides uniformis, and Lactobacillus acidophilus (r = 0.26, 0.29, 0.26, p-value < 0.05, respectively). Non-significant difference was noted in the microbial α-diversity and ß-diversity in low and high soluble/insoluble dietary fiber. Conclusions: Current findings suggest that insoluble dietary-fiber intake is favorably correlated with the health of the human gut microbiota. However, further investigations are necessary to identify the effect of types of fiber on the specific species identified in this study.

Shared and Distinct Gut Microbial Profiles in Saudi Women with Metabolically Healthy and Unhealthy Obesity.

BACKGROUND: Mounting evidence suggests a pivotal role for the gut microbiome in energy disequilibrium characteristic of obesity. The clinical utility of microbial profiling for the distinction between metabolically healthy obesity (MHO) and metabolically unhealthy obesity (MUO) remains ill-defined. We aim to probe microbial composition and diversity in young adult Saudi females with MHO and MUO. This observational study included anthropometric and biochemical measurements and shotgun sequencing of stool DNA for 92 subjects. α- and ß-diversity metrics were calculated to determine the richness and variability in microbial communities, respectively. Results showed that Bacteroides and Bifidobacterium merycicum were less abundant in MUO compared to healthy and MHO groups. BMI was negatively correlated with B. adolescentis, B. longum, and Actinobacteria in MHO, while being positively correlated with Bacteroides thetaiotaomicron in both MHO and MUO. Positive correlations between waist circumference and B. merycicum and B. thetaiotaomicron were observed in MHO and MUO, respectively. Compared to MHO and MUO groups, higher α-diversity was detected in healthy individuals who also had higher ß-diversity compared to those with MHO. We conclude that modulation of the gut microbiome cohorts through prebiotics, probiotics, and fecal microbiota transplantation may be a promising preventive and therapeutic approach to obesity-associated disease.

Metagenomic Shotgun Sequencing Reveals Specific Human Gut Microbiota Associated with Insulin Resistance and Body Fat Distribution in Saudi Women.

(1) Background: Gut microbiota dysbiosis may lead to diseases such as insulin resistance and obesity. We aimed to investigate the relationship between insulin resistance, body fat distribution, and gut microbiota composition. (2) Methods: The present study included 92 Saudi women (18-25 years) with obesity (body mass index (BMI) ≥ 30 kg/m2, n = 44) and with normal weight (BMI 18.50-24.99 kg/m2, n = 48). Body composition indices, biochemical data, and stool samples were collected. The whole-genome shotgun sequencing technique was used to analyze the gut microbiota. Participants were divided into subgroups stratified by the homeostatic model assessment for insulin resistance (HOMA-IR) and other adiposity indices. (3) Results: HOMA-IR was inversely correlated with Actinobacteria (r = -0.31, p = 0.003), fasting blood glucose was inversely correlated with Bifidobacterium kashiwanohense (r = -0.22, p = 0.03), and insulin was inversely correlated with Bifidobacterium adolescentis (r = -0.22, p = 0.04). There were significant differences in α- and ß-diversities in those with high HOMA-IR and waist-hip ratio (WHR) compared to low HOMA-IR and WHR (p = 0.02, 0.03, respectively). (4) Conclusions: Our findings highlight the relationship between specific gut microbiota at different taxonomic levels and measures of glycemic control in Saudi Arabian women. Future studies are required to determine the role of the identified strains in the development of insulin resistance.

Serum Vitamin D Level and Gut Microbiota in Women.

Obesity and vitamin D deficiency are two major public health concerns. Evidence suggests that alteration in gut microbiota composition is a possible risk factor for obesity. Additionally, altered vitamin D status has a potential role in shaping the gut microbial community. Further, the prevalence of obesity has been rising in the Middle East, especially among women of reproductive age, which is of specific concern due to its adverse effects on the health of their offspring. To date, limited evidence is available on the association between gut microbiota composition and vitamin D levels in Arab women. This study aims to identify the associations between serum vitamin D, gut microbiota, and obesity among Saudi females. The current study is a case-control study including 92 women aged 18 to 25 years, (n = 48) with normal weight and (n = 44) with obesity. Anthropometric, biochemical, lifestyle data, and fecal samples were collected and analyzed. We used shotgun metagenomic sequencing to characterize microbial communities of stool samples. Vitamin D levels were significantly associated with alpha and beta diversities. Serum vitamin D levels were positively associated with bacteria known to regulate immunological responses; Bacteroides thetaiotaomicron in the normal weight group (r = 0.34, p = 0.03) and Bifidobacterium adolescentis in the obesity group (r = 0.33, p = 0.04). In conclusion, the findings suggest that vitamin D status may play a role in regulating the gut microbiota composition by inhibiting the growth of pathogenic bacteria while nourishing the beneficial strains.

Red and White Meat Intake in Relation to Gut Flora in Obese and Non-Obese Arab Females.

BACKGROUND: high meat intake may contribute to several chronic diseases including obesity. However, evidence is insufficient on the relation between red/white meat intake and gut flora among individuals with varying degrees of adiposity. OBJECTIVE: investigate the association of red/white meat intake with gut flora in Saudi Arabian females with/without obesity. METHODS: this observational study involved 92 females with and without obesity (n = 44, 48, respectively) aged 19-25 years. The whole-genome shotgun technique was used to analyze the gut flora. Shannon alpha and Bray-Curtis beta diversity as well as correlation coefficients were used. RESULTS: in the total sample, there were positive correlations between Actinobacteria, Bacteroides (p ≤ 0.05), Flavonifractor plautii (p ≤ 0.0001), and total red meat intake. There were also positive correlations between total white meat intake, Bacteroides, and Faecalibacterium prausnitzii (p ≤ 0.05) in the total sample. In the group without obesity, there was a positive correlation between low white meat intake and Actinobacteria (p = 0.05). In the group with obesity, there was a positive correlation between high white meat intake and Bacteroides (p ≤ 0.001). CONCLUSION: our findings suggest that meat intake had an impact on the gut flora of Arab adult females, independent of adiposity. Specific strains identified in this study need further investigation to determine their relation to meat intake and obesity.

Vitamin B12 Status and Gut Microbiota among Saudi Females with Obesity.

Previous studies have suggested that dietary habits and dysbiosis of gut microbiota contributed to obesity development. Vitamin B12 is produced by microbes; however, the relationships between vitamin B12, gut microbiome, and obesity are understudied. We aimed to determine the association between vitamin B12 status and gut microbiota relative to obesity in 92 Saudi Arabian females aged 19-25 years who were obese (n = 44) or normal weight (n = 48). Anthropometric, biochemical data, and dietary data were collected. The microbial communities of stool samples were characterized using the shotgun metagenomic sequencing technique. The relationship between vitamin B12 status and gut microbiota composition was identified using Pearson correlation analysis. A statistically significant difference was found in bacterial α- and ß-diversity between the groups relative to median serum vitamin B12 level (404.0 pg/mL) and body weight. In the total participants, dietary vitamin B12 intake was inversely correlated with Bifidobacterium kashiwanohense and Blautia wexlerae species. In obese participants, dietary vitamin B12 intake was inversely correlated with Akkermansia muciniphila species and species from the Verrucomicrobia phylum, whereas it was positively correlated with Bacteroides species. Our findings indicate that the abundance (frequency) and diversity (richness) of gut microbiota are associated with vitamin B12 levels and obesity in young females.

Influence of Adiposity on the Gut Microbiota Composition of Arab Women: A Case-Control Study.

Recent evidence has suggested that the gut microbiota is a possible risk factor for obesity. However, limited evidence is available on the association between the gut microbiota composition and obesity markers in the Middle-Eastern region. We aimed to investigate the association between gut microbiota and obesity markers in a case-control study including 92 Saudi women aged 18-25 years, including participants with obesity (case, n = 44) and with normal weight (control, n = 48). Anthropometric, body composition, and biochemical data were collected. The whole-genome shotgun technique was used to analyze the gut microbiota. The Shannon alpha and Bray-Curtis beta diversity were determined. The microbial alpha diversity was significantly associated with only the waist-to-hip ratio (WHR) (p-value = 0.04), while the microbial beta diversity was significantly associated with body mass index (p-value = 0.048), %body fat (p-value = 0.018), and WHR (p-value = 0.050). Specific bacteria at different taxonomic levels, such as Bacteroidetes and Synergistetes, were positively associated with different obesity markers. Alistipes was higher in the control group compared with the case group. The results highlight the association of the gut microbiota with obesity and suggest that the gut microbiota of Saudi women is associated with specific obesity markers. Future studies are needed to determine the role of the identified strains in the metabolism of individuals with obesity.

Dietary Polyphenols in Relation to Gut Microbiota Composition in Saudi Arabian Females.

Polyphenols may modulate gut microbiota; however, limited studies have examined this relationship relative to obesity. We aim to investigate the association between polyphenol intake and gut microbiota composition in relation to obesity indices among Saudi Arabian females. This study included 92 adults stratified by body mass index (BMI) into controls (BMI ≥ 18.5−24.9 kg/m2; n = 48) and cases (BMI ≥ 30.0 kg/m2; n = 44), and further divided into high and low polyphenol intake by median intake (252 mg/1000 kcal/day). Fecal samples were collected to analyze the gut microbiota composition via the whole-genome shotgun sequencing technique. Results showed that Flavonifractor plautii and Clostridium bolteae were positively correlated with polyphenol intake in the total sample (r = 0.22, p = 0.03; r = 0.28, p = 0.01, respectively). There were inverse correlations between Blautia wexlerae and polyphenol intake (r = −0.56, p < 0.01) in the case group, and between Bacteroides thetaiotaomicron and polyphenol intake (r = −0.45, p = 0.03) in the control group. Those in the case group with low polyphenol intake, and those with high waist-to-hip ratio (WHR; ≥0.83), showed significantly lower alpha-diversity than those in the control group with normal WHR (<0.83), (p < 0.05). Findings suggest that polyphenols are correlated with specific bacteria and may play an important role in the modulation of gut microbiota and obesity management.