Grapes And Their Impact On Digestive Wellness

  • Sharaf Ahammed Graduate in MSc Microbiome in health and disease, King's College London
  • Jasmine Abdy Bachelor of Science - BSc, Medical Microbiology with a Year in Industry, University of Bristol

Get health & wellness advice into your inbox

Your privacy is important to us. Any information you provide to us via this website may be placed by us on servers. If you do not agree to these placements, please do not provide the information.

Best Milk Alternative

Grapes are ovular fruits that are nutritious and versatile. They can be eaten fresh or turned into juice, vinegar, wine or raisins. Studies have shown that consuming grapes has a variety of different health benefits including eye health,1 maintaining blood sugar levels2 and providing a source of protective antioxidants.3 Grapes also play a crucial role in the digestive system as it is high in fibre and potassium.4,5

Here are some of the ways grapes aid in digestive wellness:

Acting as natural pre-biotics:

Due to high fibre and water content, this ensures a healthy digestive system which can promote regular and healthy bowel movements. Grapes can therefore act as a natural pre-biotic.6,7 Pre-biotics are compounds, often non-digestible, which encourage the growth of healthy microorganisms to incur some sort of health benefit to the individual consuming them.8 This is one of the ways pre-biotics modulate the gut microbiome by encouraging the growth of beneficial gut microorganisms. Naturally, gut bacteria play an important role in the fermentation of fibre, which produces short-chain fatty acids, many of which play different roles in health. Furthermore, grapes are high in polyphenols such as resveratrol which also have pre-biotic effects by promoting the growth of beneficial bacteria.9 

Antioxidant and anti-inflammatory effects:

The liver is one of the most important organs in the digestive system. It is responsible for breaking down xenobiotic products which are chemicals that are not naturally found in the human body.10 Any hepatic injury can lead to severe health complications. Viral infection, metabolic diseases, alcohol, and drug abuse are some common factors which damage the liver. These can lead to the fibrosis of the liver, which can potentially lead to liver cirrhosis which can progressively lead to cancer,11 particularly when the liver is exposed to high levels of toxins from overconsumption of alcohol.12 Currently, there has been a focus on treating hepatic disorders through medicinal plants due to the adverse side effects of using synthetic drugs on the liver.

Grapes come into play here as certain polyphenol compounds contain anti-oxidant and anti-inflammatory properties.13 Resveratrol (RES) in particular, is a polyphenol commonly found in red wine and grapes.13,14 They can reduce DNA damage through the purification of hydroxyl radicals. The liver metabolises RES using liver phase II enzymes which allows for this polyphenol to be absorbed into the liver and the human body.15 Soon after, its metabolites are cleared up through urine and bile. RES has also been shown to decrease fibrosis of the liver. Studies have shown that RES administration in cirrhotic mice increased acetylcholine responsiveness and increased endothelial nitric oxide which is linked to a decrease in hepatic fibrosis. Therefore, the consumption of grapes naturally increases levels of RES which have shown to have numerous health benefits related to the liver. 

Increasing gastrointestinal motility

Grape seed powder is extracted from grape seeds and is known to have a variety of health benefits. They contain antioxidant, anti-inflammatory and antimicrobial properties.17, 18, 19, 20 They also protect against diabetes, obesity and cancer. Gastrointestinal motility refers to the movement of food throughout the digestive system. This changes depending on the food consumed and is regulated through the relaxation and contraction of smooth muscles21 in the digestive system as well as through neurons, hormones and interstitial cells of Cajal (ICC) which are known as pacemakers of the digestive system.22 Grapeseed powder can affect gastrointestinal motility and also interact with ICCs. One study done on mice has shown that grapeseed powder increased the time taken for the ingested food to pass through the intestine and this is also thought to be closely linked to ICC pacemaker activation.22 Not all grapes contain seeds but the variety of different components within the grape can confer many health benefits in the digestive system. 

Increasing microbial diversity of the gut

Studies have shown that the consumption of grapes significantly increases the diversity of gut bacteria. The gut microbiome is the full genetic composition of the bacteria present in the gut. The gut microbiota refers to the microbial species present. These two terms are often used interchangeably but they both show an indication of the bacterial composition present in the gut which in turn, gives an indication of how healthy the gut is. Generally, a diverse microbiome is an indicator of a healthy microbiome. When the body is subjected to different stresses, often the gut is impacted and it can lead to a lack of bacterial diversity. Certain bacteria associated with disease can be present in the gut. When found at high levels, they cause significant damage to the overall health and well-being of the individual. A healthy and balanced diet is one of the key factors which impact the gut microbiome. Although the gut microbiome can be impacted by genetics and environmental factors which cannot always be controlled, the microbiome is often changing with age and this can be altered through diet and exercise. Consumption of fruit and vegetables has a positive impact on the gut. This includes grapes.23 

Cholesterol metabolism

Another way in which grapes aid in digestive health is through maintaining cholesterol metabolism. Studies have shown that the consumption of grapes decreases cholesterol levels and bile acids.24 An increase in cholesterol is also linked with high blood pressure and heart health. This suggests that grapes not only play a role in digestive health but also maintain cholesterol levels which can potentially maintain blood pressure and reduce the risk of heart disease by inducing less stress to the heart.25 It is important to ensure a healthy lifestyle through exercise to reduce the risk of heart disease and obesity. Active individuals are significantly less likely to suffer from heart disease. 


In conclusion, grapes are high in fibre, vitamins and polyphenols which give them many different antioxidant and anti-inflammatory effects. This is because they act as natural free radical scavengers and can also interact with cytokines like IL-6 and C-reactive proteins.22 They boost natural physiological processes. They play a role in improving hyperglycemia which is associated with obesity and have shown to have anti-cancer properties through prevention of tumorigenesis. They play a role in ensuring a healthy liver by reducing the risk of liver fibrosis as the different compounds found in grapes can help down toxic products and decrease hepatic disorders. They also have pre-biotic effects due to high fibre content which further provides an improved gastrointestinal motility as well as promoting a more diverse gut microbiome. The different compounds found in grapes have great many effects on the human body and incorporating them into the diet can help protect against many different diseases and ensure a healthier digestive system. 


  1. Namdar H, Emaratkar E, Hadavand MB. Persian traditional medicine and ocular health. Medical Hypothesis, Discovery and Innovation in Ophthalmology. 2015;4(4):162.
  2. Grohmann T, Litts C, Horgan G, Zhang X, Hoggard N, Russell W, de Roos B. Efficacy of bilberry and grape seed extract supplement interventions to improve glucose and cholesterol metabolism and blood pressure in different populations—A systematic review of the literature. Nutrients. 2021 May 17;13(5):1692.
  3. Kanner J, Frankel E, Granit R, German B, Kinsella JE. Natural antioxidants in grapes and wines. Journal of Agricultural and Food Chemistry. 1994 Jan;42(1):64-9.
  4. Imran M, Rauf A, Imran A, Nadeem M, Ahmad Z, Atif M, Awais M, Sami M, Fatima Z, Waqar BA. Health benefits of grapes polyphenols. J. Environ. Agric. Sci. 2017;10:40-51.
  5. Beres C, Freitas SP, de Oliveira Godoy RL, de Oliveira DC, Deliza R, Iacomini M, Mellinger-Silva C, Cabral LM. Antioxidant dietary fibre from grape pomace flour or extract: Does it make any difference on the nutritional and functional value?. Journal of functional foods. 2019 May 1;56:276-85.
  6. Agte V, Khetmalis N, Nilegaonkar S, Karkamkar S, Yadav S. Prebiotic potential of ‘juice grape’varieties and some hybrids.
  7. Oliver L, Ramió-Pujol S, Amoedo J, Malagón M, Serrano M, Bahí A, Lluansí A, Torrealba L, Busquets D, Pardo L, Serra-Pagès M. A novel grape-derived prebiotic selectively enhances abundance and metabolic activity of butyrate-producing bacteria in faecal samples. Frontiers in Microbiology. 2021 Mar 23;12:639948.
  8. Hutkins RW, Krumbeck JA, Bindels LB, Cani PD, Fahey Jr G, Goh YJ, Hamaker B, Martens EC, Mills DA, Rastal RA, Vaughan E. Prebiotics: why definitions matter. Current opinion in biotechnology. 2016 Feb 1;37:1-7.
  9. Hu D, Yang W, Mao P, Cheng M. Combined amelioration of prebiotic resveratrol and probiotic Bifidobacteria on obesity and nonalcoholic fatty liver disease. Nutrition and Cancer. 2021 Apr 21;73(4):652-61.
  10. Shirani K, Yousefsani BS, Shirani M, Karimi G. Protective effects of naringin against drugs and chemical toxins induced hepatotoxicity: A review. Phytotherapy Research. 2020 Aug;34(8):1734-44.
  11. Lin W, Wu Y, Wang J, Lin H, Xu X, He G, He B, Ma X. Network pharmacology study of the hepatoprotective effects of quercetin-containing traditional Chinese medicine, Anoectochilus roxburghii, and validation of quercetin as an anti-liver injury agent in a mouse model of liver injury. Medical Science Monitor: International Medical Journal of Experimental and Clinical Research. 2020;26:e923533-1.
  12. Seki E, Brenner DA. Recent advancement of molecular mechanisms of liver fibrosis. Journal of Hepato‐Biliary‐Pancreatic Sciences. 2015 Jul;22(7):512-8.
  13. Chupradit S, Bokov D, Zamanian MY, Heidari M, Hakimizadeh E. Hepatoprotective and therapeutic effects of resveratrol: A focus on anti‐inflammatory and antioxidative activities. Fundamental & clinical pharmacology. 2022 Jun;36(3):468-85.
  14. Hessin AF, Hegazy RR, Hassan AA, Yassin NZ, Kenawy SA. Resveratrol prevents liver fibrosis via two possible pathways: Modulation of alpha fetoprotein transcriptional levels and normalization of protein kinase C responses. Indian journal of pharmacology. 2017 Jul;49(4):282.
  15. Jalili C, Salahshoor MR, Jalili F, Kakabaraei S, Akrami A, Sohrabi M, Ahookhash M, Ghanbari A. Therapeutic Effect of Resveratrol on Morphine-Induced Damage in Male Reproductive System of Mice by Reducing Nitric Oxide Serum Level. International Journal of Morphology. 2017 Dec 1;35(4).
  16. Izzo C, Annunziata M, Melara G, Sciorio R, Dallio M, Masarone M, Federico A, Persico M. The role of resveratrol in liver disease: A comprehensive review from in vitro to clinical trials. Nutrients. 2021 Mar 13;13(3):933.
  17. Katsuda Y, Niwano Y, Nakashima T, Mokudai T, Nakamura K, Oizumi S, Kanno T, Kanetaka H, Egusa H. Cytoprotective effects of grape seed extract on human gingival fibroblasts in relation to its antioxidant potential. PLoS One. 2015 Aug 10;10(8):e0134704.
  18. Cheah KY, Bastian SE, Acott TM, Abimosleh SM, Lymn KA, Howarth GS. Grape seed extract reduces the severity of selected disease markers in the proximal colon of dextran sulphate sodium-induced colitis in rats. Digestive diseases and sciences. 2013 Apr;58:970-7.
  19. Hogan S, Canning C, Sun S, Sun X, Kadouh H, Zhou K. Dietary supplementation of grape skin extract improves glycemia and inflammation in diet-induced obese mice fed a Western high fat diet. Journal of agricultural and food chemistry. 2011 Apr 13;59(7):3035-41.
  20. Vislocky LM, Fernandez ML. Biomedical effects of grape products. Nutrition reviews. 2010 Nov 1;68(11):656-70.
  21. Sanders KM, Koh SD, Ro S, Ward SM. Regulation of gastrointestinal motility—insights from smooth muscle biology. Nature reviews Gastroenterology & hepatology. 2012 Nov;9(11):633-45.
  22. Choi NR, Kim JN, Kwon MJ, Lee JR, Kim SC, Lee MJ, Choi WG, Kim BJ. Grape seed powder increases gastrointestinal motility. International Journal of Medical Sciences. 2022;19(5):941.
  23. Yang J, Kurnia P, Henning SM, Lee R, Huang J, Garcia MC, Surampudi V, Heber D, Li Z. Effect of standardized grape powder consumption on the gut microbiome of healthy subjects: a pilot study. Nutrients. 2021 Nov;13(11):3965.
  24. Del Bas JM, Crescenti A, Arola-Arnal A, Oms-Oliu G, Arola L, Caimari A. Intake of grape procyanidins during gestation and lactation impairs reverse cholesterol transport and increases atherogenic risk indexes in adult offspring. The Journal of nutritional biochemistry. 2015 Dec 1;26(12):1670-7.
  25. Dohadwala MM, Vita JA. Grapes and cardiovascular disease. The Journal of nutrition. 2009 Sep 1;139(9):1788S-93S.

Get health & wellness advice into your inbox

Your privacy is important to us. Any information you provide to us via this website may be placed by us on servers. If you do not agree to these placements, please do not provide the information.

Best Milk Alternative
[optin-monster-inline slug="yw0fgpzdy6fjeb0bbekx"]
This content is purely informational and isn’t medical guidance. It shouldn’t replace professional medical counsel. Always consult your physician regarding treatment risks and benefits. See our editorial standards for more details.

Get our health newsletter

Get daily health and wellness advice from our medical team.
Your privacy is important to us. Any information you provide to this website may be placed by us on our servers. If you do not agree do not provide the information.

Sharaf Ahammed

Graduate in MSc Microbiome in health and disease, King's College London

I have a strong background in microbiology and an immense love for writing. I have many years of experience in science communication through writing and editing blogs as well as content creation. I am also fond of creative writing, with two published books of poetry which are currently sold online. I wish to share my passion for science through writing. presents all health information in line with our terms and conditions. It is essential to understand that the medical information available on our platform is not intended to substitute the relationship between a patient and their physician or doctor, as well as any medical guidance they offer. Always consult with a healthcare professional before making any decisions based on the information found on our website.
Klarity is a citizen-centric health data management platform that enables citizens to securely access, control and share their own health data. Klarity Health Library aims to provide clear and evidence-based health and wellness related informative articles. 
Klarity / Managed Self Ltd
Alum House
5 Alum Chine Road
Westbourne Bournemouth BH4 8DT
VAT Number: 362 5758 74
Company Number: 10696687

Phone Number:

 +44 20 3239 9818