The Carnivore Diet and Gut Health: Mechanisms, Benefits and Risks
DOI:
https://doi.org/10.12775/QS.2025.48.67053Keywords
Carnivore Diet, Inflammatory Bowel Diseases, Ketone Bodies, Intestinal Microbiota, Gastrointestinal Diseases, Dietary ProteinsAbstract
Introduction:
The carnivore diet, composed exclusively of animal-sourced foods, has gained attention both as a nutritional trend and as a potential therapeutic strategy for gastrointestinal conditions. It excludes plant-based foods, resulting in markedly reduced carbohydrate and fiber intake. While some studies suggest clinical benefits, the underlying mechanisms and long-term safety remain controversial.
Aim of the study:
This review aims to evaluate the effects of the carnivore diet on gut health by exploring its physiological mechanisms, clinical benefits in intestinal diseases, and associated risks.
Materials and Methods:
A literature review was conducted, analyzing data on the carnivore diet's influence on gut microbiota, inflammatory markers, nutrient status, and clinical outcomes in conditions such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and small intestinal bacterial overgrowth (SIBO). Publications from 2005 to 2025 were analyzed, with the majority from 2020 to 2024.
Results:
Evidence suggests that ketone bodies produced on a carnivore diet modulate inflammation through macrophage polarization and epigenetic pathways. Some case reports indicate symptom improvement in IBD and IBS, potentially due to reduced dietary antigens and fermentable carbohydrates. However, the diet’s exclusion of fiber impacts microbiome composition and short-chain fatty acid production, posing risks to mucosal integrity. Additionally, high consumption of red and processed meats may elevate cancer risk due to carcinogenic compounds and hormonal additives.
Conclusions:
While the carnivore diet may offer symptomatic relief in selected gastrointestinal disorders, its restrictive nature, potential nutrient deficiencies, and long-term health risks necessitate further controlled studies. Clinical implementation should be approached cautiously and under professional supervision.
References
1. Palmer RD. The protein paradox, carnivore diet & hypertrophy versus longevity.: Short term nutrition and hypertrophy versus longevity. Nutr Health. Published online March 17, 2025. doi:10.1177/02601060251314575
2. Lennerz BS, Mey JT, Henn OH, Ludwig DS. Behavioral Characteristics and Self-Reported Health Status among 2029 Adults Consuming a "Carnivore Diet". Curr Dev Nutr. 2021;5(12):nzab133. Published 2021 Nov 2. doi:10.1093/cdn/nzab133
3. Norwitz NG, Soto-Mota A. Case report: Carnivore-ketogenic diet for the treatment of inflammatory bowel disease: a case series of 10 patients. Front Nutr. 2024;11:1467475. Published 2024 Sep 2. doi:10.3389/fnut.2024.1467475
4. Huang C, Wang J, Liu H, et al. Ketone body β-hydroxybutyrate ameliorates colitis by promoting M2 macrophage polarization through the STAT6-dependent signaling pathway. BMC Med. 2022;20(1):148. Published 2022 Apr 15. doi:10.1186/s12916-022-02352-x
5. Khoziainova S, Rozenberg G, Levy M. Ketogenic Diet and Beta-Hydroxybutyrate in Colorectal Cancer. DNA Cell Biol. 2022;41(12):1007-1011. doi:10.1089/dna.2022.0486
6. Diakité MT, Diakité B, Koné A, et al. Relationships between gut microbiota, red meat consumption and colorectal cancer. J Carcinog Mutagen. 2022;13(3):1000385.
7. Turesky RJ. Mechanistic evidence for red meat and processed meat intake and cancer risk: a follow-up on the International Agency for Research on Cancer evaluation of 2015. Chimia (Aarau). 2018;72(10):718-724. doi:10.2533/chimia.2018.718.
8. Goedeke S, Murphy T, Rush A, Zinn C. Assessing the Nutrient Composition of a Carnivore Diet: A Case Study Model. Nutrients. 2024;17(1):140. Published 2024 Dec 31. doi:10.3390/nu17010140
9. Sonnenburg ED, Smits SA, Tikhonov M, Higginbottom SK, Wingreen NS, Sonnenburg JL. Diet-induced extinctions in the gut microbiota compound over generations. Nature. 2016;529(7585):212-215. doi:10.1038/nature16504
10. ,Dell'Olio A, Scott WT Jr, Taroncher-Ferrer S, et al. Tailored impact of dietary fibers on gut microbiota: a multi-omics comparison in lean and obese microbial communities. Microbiome. 2024;12:250. doi:10.1186/s40168-024-01975-x
11. Holscher HD. Dietary fiber and prebiotics and the gastrointestinal microbiota. Gut Microbes. 2017;8(2):172-184. doi:10.1080/19490976.2017.1290756
12. Neufingerl N, Eilander A. Nutrient Intake and Status in Adults Consuming Plant-Based Diets Compared to Meat-Eaters: A Systematic Review. Nutrients. 2021;14(1):29. Published 2021 Dec 23. doi:10.3390/nu14010029
13. Mardinoglu A, Wu H, Bjornson E, et al. An Integrated Understanding of the Rapid Metabolic Benefits of a Carbohydrate-Restricted Diet on Hepatic Steatosis in Humans. Cell Metab. 2018;27(3):559-571.e5. doi:10.1016/j.cmet.2018.01.005
14. Slavin J. Fiber and prebiotics: mechanisms and health benefits. Nutrients. 2013;5(4):1417-1435. Published 2013 Apr 22. doi:10.3390/nu5041417
15. Scott KP, Gratz SW, Sheridan PO, Flint HJ, Duncan SH. The influence of diet on the gut microbiota. Pharmacol Res. 2013;69(1):52-60. doi:10.1016/j.phrs.2012.10.020
16. Ríos-Covián D, Ruas-Madiedo P, Margolles A, Gueimonde M, de Los Reyes-Gavilán CG, Salazar N. Intestinal Short Chain Fatty Acids and their Link with Diet and Human Health. Front Microbiol. 2016;7:185. Published 2016 Feb 17. doi:10.3389/fmicb.2016.00185
17. Litvak Y, Byndloss MX, Bäumler AJ. Colonocyte metabolism shapes the gut microbiota. Science. 2018;362(6418):eaat9076. doi:10.1126/science.aat9076
18. Wu S, Bhat ZF, Gounder RS, et al. Effect of Dietary Protein and Processing on Gut Microbiota-A Systematic Review. Nutrients. 2022;14(3):453. Published 2022 Jan 20. doi:10.3390/nu14030453
19. Thulasinathan B, Suvilesh KN, Maram S, et al. The impact of gut microbial short-chain fatty acids on colorectal cancer development and prevention. Gut Microbes. 2025;17(1):2483780. doi:10.1080/19490976.2025.2483780
20. Martin-McGill KJ, Bresnahan R, Levy RG, Cooper PN. Ketogenic diets for drug-resistant epilepsy. Cochrane Database Syst Rev. 2020;6(6):CD001903. Published 2020 Jun 24. doi:10.1002/14651858.CD001903.pub5
21. Zhang H, Su Q. Low-FODMAP Diet for Irritable Bowel Syndrome: Insights from Microbiome. Nutrients. 2025;17(3):544. Published 2025 Jan 31. doi:10.3390/nu17030544
22. Limketkai BN, Godoy-Brewer G, Parian AM, et al. Dietary Interventions for the Treatment of Inflammatory Bowel Diseases: An Updated Systematic Review and Meta-analysis. Clin Gastroenterol Hepatol. 2023;21(10):2508-2525.e10. doi:10.1016/j.cgh.2022.11.026
23. Gibson PR, Shepherd SJ. Evidence-based dietary management of functional gastrointestinal symptoms: The FODMAP approach. J Gastroenterol Hepatol. 2010;25(2):252-258. doi:10.1111/j.1440-1746.2009.06149.x
24. Gearry RB, Irving PM, Barrett JS, Nathan DM, Shepherd SJ, Gibson PR. Reduction of dietary poorly absorbed short-chain carbohydrates (FODMAPs) improves abdominal symptoms in patients with inflammatory bowel disease-a pilot study. J Crohns Colitis. 2009;3(1):8-14. doi:10.1016/j.crohns.2008.09.004
25. Sachdev AH, Pimentel M. Gastrointestinal bacterial overgrowth: pathogenesis and clinical significance. Ther Adv Chronic Dis. 2013;4(5):223-231. doi:10.1177/2040622313496126
26. Achufusi TGO, Sharma A, Zamora EA, Manocha D. Small Intestinal Bacterial Overgrowth: Comprehensive Review of Diagnosis, Prevention, and Treatment Methods. Cureus. 2020;12(6):e8860. Published 2020 Jun 27. doi:10.7759/cureus.8860
27. Wielgosz-Grochowska JP, Domanski N, Drywień ME. Efficacy of an Irritable Bowel Syndrome Diet in the Treatment of Small Intestinal Bacterial Overgrowth: A Narrative Review. Nutrients. 2022;14(16):3382. Published 2022 Aug 17. doi:10.3390/nu14163382
28. Souza C, Rocha R, Cotrim HP. Diet and intestinal bacterial overgrowth: Is there evidence?. World J Clin Cases. 2022;10(15):4713-4716. doi:10.12998/wjcc.v10.i15.4713
29. Diallo A, Deschasaux M, Latino-Martel P, et al. Red and processed meat intake and cancer risk: Results from the prospective NutriNet-Santé cohort study. Int J Cancer. 2018;142(2):230-237. doi:10.1002/ijc.31046
30. Farah E, Hutchinson JM, Ruan Y, O'Sullivan DE, Hilsden RJ, Brenner DR. The Association between Red Meat Consumption and Advanced Colorectal Adenomas in a Population Undergoing a Screening-Related Colonoscopy in Alberta, Canada. Cancers (Basel). 2024;16(3):495. Published 2024 Jan 24. doi:10.3390/cancers16030495
31. Lo JJ, Park YM, Sinha R, Sandler DP. Association between meat consumption and risk of breast cancer: Findings from the Sister Study. Int J Cancer. 2020;146(8):2156-2165. doi:10.1002/ijc.32547
32. Dunneram Y, Greenwood DC, Cade JE. Diet and risk of breast, endometrial and ovarian cancer: UK Women's Cohort Study. Br J Nutr. 2019;122(5):564-574. doi:10.1017/S0007114518003665
33. Cross AJ, Leitzmann MF, Gail MH, Hollenbeck AR, Schatzkin A, Sinha R. A prospective study of red and processed meat intake in relation to cancer risk. PLoS Med. 2007;4(12):e325. doi:10.1371/journal.pmed.0040325
34. Ma Y, Yang W, Li T, et al. Meat intake and risk of hepatocellular carcinoma in two large US prospective cohorts of women and men. Int J Epidemiol. 2019;48(6):1863-1871. doi:10.1093/ije/dyz146
35. Poorolajal J, Mohammadi Y, Fattahi-Darghlou M, Almasi-Moghadam F. The association between major gastrointestinal cancers and red and processed meat and fish consumption: A systematic review and meta-analysis of the observational studies. PLoS One. 2024;19(6):e0305994. Published 2024 Jun 26. doi:10.1371/journal.pone.0305994
36. Gamage SMK, Dissabandara L, Lam AK, Gopalan V. The role of heme iron molecules derived from red and processed meat in the pathogenesis of colorectal carcinoma. Crit Rev Oncol Hematol. 2018;126:121-128. doi:10.1016/j.critrevonc.2018.03.025
37. Tappel A. Heme of consumed red meat can act as a catalyst of oxidative damage and could initiate colon, breast and prostate cancers, heart disease and other diseases. Med Hypotheses. 2007;68(3):562-564. doi:10.1016/j.mehy.2006.08.025
38. Seiwert N, Wecklein S, Demuth P, et al. Heme oxygenase 1 protects human colonocytes against ROS formation, oxidative DNA damage and cytotoxicity induced by heme iron, but not inorganic iron. Cell Death Dis. 2020;11(9):787. Published 2020 Sep 23. doi:10.1038/s41419-020-02950-8
39. Bulanda S, Janoszka B. Consumption of Thermally Processed Meat Containing Carcinogenic Compounds (Polycyclic Aromatic Hydrocarbons and Heterocyclic Aromatic Amines) versus a Risk of Some Cancers in Humans and the Possibility of Reducing Their Formation by Natural Food Additives-A Literature Review. Int J Environ Res Public Health. 2022;19(8):4781. Published 2022 Apr 14. doi:10.3390/ijerph19084781
40. Pogorzelska-Nowicka E, Kurek M, Hanula M, Wierzbicka A, Półtorak A. Formation of Carcinogens in Processed Meat and Its Measurement with the Usage of Artificial Digestion-A Review. Molecules. 2022;27(14):4665. Published 2022 Jul 21. doi:10.3390/molecules27144665
41. Molina-Montes E, Salamanca-Fernández E, Garcia-Villanova B, Sánchez MJ. The Impact of Plant-Based Dietary Patterns on Cancer-Related Outcomes: A Rapid Review and Meta-Analysis. Nutrients. 2020;12(7):2010. Published 2020 Jul 6. doi:10.3390/nu12072010
42. Miziak P, Baran M, Błaszczak E, et al. Estrogen Receptor Signaling in Breast Cancer. Cancers (Basel). 2023;15(19):4689. Published 2023 Sep 23. doi:10.3390/cancers15194689
43. Schneider HP, Mueck AO, Kuhl H. IARC monographs program on carcinogenicity of combined hormonal contraceptives and menopausal therapy. Climacteric. 2005;8(4):311-316. doi:10.1080/13697130500345299
44. Nachman KE, Smith TJ. Hormone Use in Food Animal Production: Assessing Potential Dietary Exposures and Breast Cancer Risk. Curr Environ Health Rep. 2015;2(1):1-14. doi:10.1007/s40572-014-0042-8
Downloads
Published
How to Cite
Issue
Section
License
Copyright (c) 2025 Aleksander Tuteja, Katarzyna Trala, Laura Więcko, Liwia Olczyk, Klaudia Burzykowska, Kamila Gęborys, Mikołaj Tyla, Rema Mohaissen, Patryk Stabrawa, Konrad Krupa

This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
Stats
Number of views and downloads: 3
Number of citations: 0