Punit Desai

Background:  Cardiometabolic diseases—including cardiovascular disease (CVD), type 2 diabetes, obesity, hypertension, and metabolic syndrome—represent a major global health burden, contributing significantly to morbidity, mortality, and economic costs. Recent research has highlighted the role of gut microbiota-derived metabolites such as trimethylamine N-oxide (TMAO) and short-chain fatty acids (SCFAs) in influencing the risk of developing these conditions^1,2 . While large-scale clinical studies have established associations between these metabolites and cardiometabolic risk, the underlying mechanisms remain under investigation. Emerging evidence suggests that diet may offer a promising avenue for reshaping the gut microbiome and potentially providing protective effects. However, more work is needed to understand exactly how dietary interventions influence microbial composition and metabolite production. This review explores current findings and aims to address gaps in understanding the preventative and therapeutic potential of diet-induced microbiome modulation in managing cardiometabolic diseases.

Methods:  Multiple PubMed queries were conducted to identify resource sources. For literature on diet and the gut microbiome, queries included terms such as “vegan diet and the gut microbiome.” Studies examining the relationship between the gut microbiome and cardiometabolic health were identified using searches like “role of gut microbiome in cardiometabolic diseases.” Additional articles focusing on plasma TMAO were retrieved using terms such as “trimethylamine N-oxide and cardiometabolic health” and “gut microbiome effects on plasma trimethylamine N-oxide and cardiometabolic health.”

Results:  A randomized controlled trial assigned 168 participants to either a low-fat vegan group (n=84) or a control group (n=84). At the end of the 16-week trial, the vegan group had statistically significant reductions in weight and visceral fat, along with improved insulin sensitivity. These benefits were hypothesized to result from increased relative abundance of Faecalibacterium and Bacteroides species³.  Additionally, a multinational metagenomic analysis involving 21,561 adults from five cohorts found that dietary patterns leave distinct, health-relevant signatures in the gut microbiome. Greater diversity in plant-based food consumption was associated with a shift toward a healthier microbial profile⁴.

Conclusion:  Diet has demonstrated powerful effects on gut microbiome composition. Increased abundance of Bacteroidetes, Faecalibacterium, and Akkermansia has been linked to reduced inflammation, improved insulin sensitivity, enhanced gut barrier integrity, and beneficial changes in body composition³,⁵. Clinically, harnessing the gut microbiome’s potential may help prevent and treat cardiometabolic diseases. Future research should focus on developing precise, microbiome-based diagnostics and interventions to improve outcomes across diverse populations.

Works Cited

1.  Fu BC, Hullar MAJ, Randolph TW, Franke AA, Monroe KR, Cheng I, Wilkens LR, Shepherd JA, Madeleine MM, Le Marchand L, Lim U, Lampe JW. Associations of plasma trimethylamine N-oxide, choline, carnitine, and betaine with inflammatory and cardiometabolic risk biomarkers and the fecal microbiome in the Multiethnic Cohort Adiposity Phenotype Study. Am J Clin Nutr. 2020 Jun 1;111(6):1226-1234. doi: 10.1093/ajcn/nqaa015. PMID: 32055828; PMCID: PMC7266689.
2. Agus A, Clément K, Sokol H. Gut microbiota-derived metabolites as central regulators in metabolic disorders. Gut. 2021 Jun;70(6):1174-1182. doi: 10.1136/gutjnl-2020-323071. Epub 2020 Dec 3. PMID: 33272977; PMCID: PMC8108286.
3. Kahleova H, Rembert E, Alwarith J, Yonas WN, Tura A, Holubkov R, Agnello M, Chutkan R, Barnard ND. Effects of a Low-Fat Vegan Diet on Gut Microbiota in Overweight Individuals and Relationships with Body Weight, Body Composition, and Insulin Sensitivity. A Randomized Clinical Trial. Nutrients. 2020 Sep 24;12(10):2917. doi: 10.3390/nu12102917. PMID: 32987642; PMCID: PMC7598634.
4. Fackelmann, G., Manghi, P., Carlino, N. et al. Gut microbiome signatures of vegan, vegetarian and omnivore diets and associated health outcomes across 21,561 individuals. Nat Microbiol 10, 41–52 (2025). https://doi.org/10.1038/s41564-024-01870-z
5. Witkowski M, Weeks TL, Hazen SL. Gut Microbiota and Cardiovascular Disease. Circ Res. 2020 Jul 31;127(4):553-570. doi: 10.1161/CIRCRESAHA.120.316242. Epub 2020 Jul 30. PMID: 32762536; PMCID: PMC7416843.