The pomegranate is a unique, ancient, transcendent fruit with historical uses in numerous systems of medicine for a range of ailments. For the body to function appropriately, the digestive system must obtain the required nutrients. What is the role of the pomegranate in digestion? This article aims to provide insight into the digestive system and the pomegranate.
The digestive system
The digestive system encompasses the gastrointestinal tract, also known as the digestive tract or GI tract, along with the pancreas, liver, and gallbladder. The digestive tract is a series of long, twisted, and hollow organs extending from the mouth to the anus. The hollow organs include the oesophagus, mouth, small intestine, large intestine, stomach, and anus. The small intestine is made up of three sections: the duodenum, jejunum, and ileum. The large intestine is made up of the cecum, appendix, rectum, and colon. The first component of the large intestine is the cecum which has the appendix attached, followed by the colon and the rectum. The gut microbiome, or flora, consists of bacteria in the digestive tract that aids digestion. Digestion is also controlled by components of the circulatory and nervous systems. Food and liquids consumed by humans are digested with support from hormones, bacteria, blood, nerves, and organs in the digestive system. The digestive system breaks down nutrients, including carbohydrates, proteins, fats, minerals, vitamins, and water into smaller molecules that can be absorbed by the body for cell repair, energy, and growth. Simple sugars are obtained from carbohydrates; amino acids from proteins; fatty acids and glycerol from fats.1 A balanced diet is key in promoting gut health and preventing complications associated with digestion such as constipation. It is recommended to ingest foods with high levels of fibre such as fruits, vegetables, brown rice, and wholemeal bread as well as drinking plenty of fluids, in addition to reducing fats and avoiding spicy foods.2
About the pomegranate
Pomegranate, or Punica granatum L, is thought to originate from Afghanistan or Iran and is grown all over Central Asia, including the Middle East, the Himalayas, the Mediterranean area and the Southwest of America.3 A pomegranate tree can live for over 200 years and typically reaches a height of 12 to 16 feet. The glossy leaves of the plant are long and narrow with a pointed tip. As the tree matures, the bark becomes grey. The flowers are red, white, large, or mottled with a tubular calyx, acting as a protective layer which will ultimately become a fruit. When ripened, the pomegranate fruit can grow up to five inches wide and the leathery skin takes a deep red colour. The fruit takes on a grenade-like shape with a pointed calyx at the top. Inside this outer layer, there are a vast number of seeds, also known as arils. The arils are separated by a pericarp, which is white and membranous, as well as small volumes of tart ruby-red juice around them.4 Pomegranates and their components have been linked to potent antifungal, antioxidant, anti-inflammatory, antimicrobial, and antibacterial effects based on studies conducted within living organisms and laboratory-based experiments.5 Additionally, it has been shown that pomegranates may demonstrate antiproliferative and anti-hypertensive effects.6 Furthermore, it has been shown that the juice or extracts of pomegranates can have positive benefits on a range of digestive diseases.7
Traditional use
The Quran is the holy book in Islam and does not mention all varieties of plants, except if that plant is the best organism of its species. Pomegranate, also known as rumman in Arabic, is found in three places in the Quran. In chapter 55 of the Quran (Surah Ar-Rahman) verses 68-69 say that “In both will be fruit, palm trees, and pomegranates. Then which of your Lord’s favors will you both deny?”.8 Commentators have mentioned that dates and pomegranates have been mentioned here over all other fruits to explain and show the virtue of these fruits. M.Quraish Shibab, a modern Indonesian commentator, has interpreted these mentionings of the pomegranates with their efficacies. For example, pomegranate juice contains very high levels of citric acid when compared to other fruits. The presence of citric acid could reduce the risk of developing kidney stones..9 Traditionally, pomegranates, as well as different parts of the plant such as the juice, flowers, or peels, have been used to treat a variety of health issues. In Islamic and Iranian Traditional Medicine (ITM), the plant has been favoured by traditional physicians for its astringent effects, which are now believed to be related to the presence of phenolic compounds such as tannins. Phenolic compounds comprise a large group of organic compounds present in plants. The chemical composition of pomegranates is dependent on the variety, maturity, growing area, climate, cultivation techniques and storage conditions10 In ITM textbooks, two kinds of this fruit are mentioned: a wild type, which is sweet, and a cultivated type, which is sour. However, 4 tastes have been mentioned by ITM scientists: sour, sweet, sweet-sour and astringent. Interestingly, nearly all parts of the plant have been used medicinally in ITM, including the calyx, peel, bark, root, leaves, seeds, fruits, stamens, and flowers. It is thought that the pomegranate is beneficial for the intestines and stomach. In ITM textbooks, it has been written that sweet pomegranate has favourable effects on digestion whilst sour pomegranates can be harmful. Thus, it is recommended that the sour pomegranate is ingested with a sweetener, such as honey or Halva Ardeh, which is an Iranian sweet composed of sugar and sesame. However, other ITM textbooks have stipulated that sour pomegranate has favourable effects on inflamed stomachs. For example, if the sweet and sour pomegranate is extracted from the mesocarp (the wall of the fruit) and then combined with red sugar, it creates stomach-strengthening agents. Additionally, the anti-parasitic effects have been mentioned, for example, a drink from pulverized pomegranate skins and warm water has been utilized to cure patients with intestinal worms.11
Modern medicine
Research has shown that different parts of the pomegranate can alleviate digestive diseases such as inflammatory diseases, gastrointestinal tumours, diarrhoea, and gastrointestinal infections.11 Diarrhoea is a result of inflammation and food moving quickly through the digestive tract. A study in a rat model has shown that the use of pomegranate extracts led to a decrease in movement and weight in the intestines which was dependent on the amount of extract used. Additionally, the extracts reduce muscle contractility in the ileum, a part of the small intestines. 12 This highlights the benefits of pomegranate in digestion and reducing diarrhoea. Furthermore, there has been a gastric-protective effect linked with pomegranate flowers and extracts in gastritis, a condition where the stomach lining is inflamed or irritated. Gastritis can be caused by the use of non-steroidal anti-inflammatory medications (NSAIDs) such as aspirin or ibuprofen. When rats were given aspirin as well as pomegranate extracts, the severity and number of gastric ulcers were reduced.13 Another study found that the powder of pomegranate flowers also reduced the percentage of gastric ulcers.14 However, it is important to note that the majority of studies which assess the pharmacological potential have been conducted preclinically with only a small amount in human clinical trials. Therefore, further clinical trials are warranted to fully elucidate the role of pomegranates and their derivatives in the digestive system.
FAQs
What are some ways I could use pomegranates?
Pomegranates can be eaten on their own for a burst of sweet flavour; blended into smoothies or juice; a sweet and crunchy addition to salads; cooked in savoury dishes using the juice or puree or even as a simple garnish in desserts.
Are there side effects associated with the consumption of pomegranates for digestion?
When eaten as a part of a balanced diet, it is beneficial for digestion and safe for most individuals. Unless an individual has an allergy to pomegranates or experiences gastrointestinal discomfort as a result of consumption of a large amount of pomegranates. If an individual has not eaten the fruit before then it is advisable to begin with small amounts and to see how the body reacts.
Summary
The pomegranate has been used for many years in traditional medicine and the potential benefit as well as the high status of the fruit has been mentioned on numerous occasions. These traditional medical uses are being studied in modern medicine but research on this is still at an early stage. Nonetheless, there has been agreement on what has been done traditionally with modern medicine. For instance, the use of pomegranates to treat gastrointestinal infections as well as the anti-inflammatory effects. Taking this into account, pomegranates have a potentially beneficial role in digestion and the incorporation of this fruit in a balanced diet should be taken into consideration.
References
- Your Digestive System & How it Works - NIDDK. National Institute of Diabetes and Digestive and Kidney Diseases [Internet]. [cited 2024 Feb 2]. Available from: https://www.niddk.nih.gov/health-information/digestive-diseases/digestive-system-how-it-works.
- Good foods to help your digestion. nhs.uk [Internet]. 2022 [cited 2024 Feb 2]. Available from: https://www.nhs.uk/live-well/eat-well/digestive-health/good-foods-to-help-your-digestion/.
- Shaygannia E, Bahmani M, Zamanzad B, Rafieian-Kopaei M. A Review Study on Punica granatum L. J Evid Based Complementary Altern Med [Internet]. 2016 [cited 2024 Jan 29]; 21(3):221–7. Available from: http://journals.sagepub.com/doi/10.1177/2156587215598039.
- Jurenka J. Therapeutic Applications of Pomegranate (Punica granatum L.): A Review. Alternative Medicine Review: a Journal of Clinical Therapeutic [Internet]. 2008; 13. Available from: https://www.researchgate.net/publication/5261934.
- Zou X, Yan C, Shi Y, Cao K, Xu J, Wang X, et al. Mitochondrial Dysfunction in Obesity-Associated Nonalcoholic Fatty Liver Disease: The Protective Effects of Pomegranate with Its Active Component Punicalagin. Antioxidants & Redox Signaling [Internet]. 2014 [cited 2024 Jan 29]; 21(11):1557–70. Available from: http://www.liebertpub.com/doi/10.1089/ars.2013.5538.
- Sharma K, Kesharwani P, Prajapati SK, Jain A, Jain D, Mody N, et al. An Insight into Anticancer Bioactives from Punica granatum (Pomegranate). ACAMC [Internet]. 2022 [cited 2024 Jan 29]; 22(4):694–702. Available from: https://www.eurekaselect.com/194965/article.
- Alkhatib M, Fayad C, Badran A, Hamade K, Daou A, Baydoun E, et al. Preventive and Therapeutic Effects of Punica granatum (Pomegranate) in Respiratory and Digestive Diseases: A Review. Applied Sciences [Internet]. 2022 [cited 2024 Jan 29]; 12(23):12326. Available from: https://www.mdpi.com/2076-3417/12/23/12326.
- Surah Ar-Rahman - 1-78. Quran.com [Internet]. [cited 2024 Feb 2]. Available from: https://quran.com/ar-rahman.
- Atabik A, Muqtada MR, Suhadi, Irnawati, Rohman A. Pomegranate (Punica granatum L.) fruits in the Quranic Hermeneutics and scientific perspectives. Food Res [Internet]. 2022 [cited 2024 Feb 3]; 6(5):1–13. Available from: https://www.myfoodresearch.com/uploads/8/4/8/5/84855864/_1__fr-2021-504_atabik.pdf.
- Wu S, Tian L. Diverse Phytochemicals and Bioactivities in the Ancient Fruit and Modern Functional Food Pomegranate (Punica granatum). Molecules [Internet]. 2017 [cited 2024 Jan 29]; 22(10):1606. Available from: http://www.mdpi.com/1420-3049/22/10/1606.
- Mohammadi M, Boghrati Z, Emami SA, Akaberi M. Pomegranate: A review of the heavenly healer’s past, present, and future. Iranian Journal of Basic Medical Sciences [Internet]. 2023 [cited 2024 Jan 29]; 26(11):1245–64. Available from: https://ijbms.mums.ac.ir/article_22898.html.
- Qnais EY, Elokda AS, Abu Ghalyun YY, Abdulla FA. Antidiarrheal Activity of the Aqueous Extract of Punica granatum . (Pomegranate) Peels. Pharmaceutical Biology [Internet]. 2007 [cited 2024 Feb 3]; 45(9):715–20. Available from: http://www.tandfonline.com/doi/full/10.1080/13880200701575304.
- Ajaikumar KB, Asheef M, Babu BH, Padikkala J. The inhibition of gastric mucosal injury by Punica granatum L. (pomegranate) methanolic extract. Journal of Ethnopharmacology [Internet]. 2005 [cited 2024 Feb 3]; 96(1–2):171–6. Available from: https://linkinghub.elsevier.com/retrieve/pii/S0378874104004386.
- Alam MS, Alam MA, Ahmad S, Najmi AK, Asif M, Jahangir T. Protective effects of Punica granatum in experimentally-induced gastric ulcers. Toxicology Mechanisms and Methods [Internet]. 2010 [cited 2024 Feb 3]; 20(9):572–8. Available from: http://www.tandfonline.com/doi/full/10.3109/15376516.2010.508079.