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The Beneficial Effects of Onions on Gut Health: A Review

Vol. 3 No. 8 (2025): International Journal of Integrative and Modern Medicine:

Noor Zuhair Bakheet NZ (1)

(1) Department of physiology and medical physics, College of Medicine, Jabir Ibn Hayyan University for Medical & Pharmaceutical science, Kuffa, Iraq, Iraq
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Abstract:

Onion (Allium cepa L.) is a common vegetable that contains fiber known as fructans, a type of soluble carbohydrate that acts as a prebiotic, fermented by intestinal bacteria, which output short-chain fatty acids (SCFAs). Fructans, a type of soluble carbohydrate, act as a prebiotic, meaning they feed the beneficial bacteria in your gut. Fermenting onions promotes antioxidant activity and raises the availability of bioactive compounds like flavonoids and SCFAs. This review underscores the benefits of a high-fiber diet, such as onions, which increases beneficial bacteria in the gut and reduces harmful bacteria. This contributes to a balanced gut microbiome homeostasis; the balanced pH in the intestine helps maintain healthy immune cells, minimizes the risk of certain diseases, and enhances overall gut health. In contrast, diets containing processed foods and low in fiber reduce beneficial bacteria, leading to an imbalance of bacteria in the gut (dysbiosis); the pH turn into unbalanced, more permeable of the intestinal barrier, leading to a status called “leaky gut,” in which toxins, bacteria, and undigested food particles leak into the bloodstream, making you more susceptible to disease. Finally, we suggest replacing low-fiber foods with high-fiber ones, as well as avoiding sugars, preservatives, and processed foods, as these positively impact the health and vitality of the gut microbiome. This is an effective approach to maintaining the society of microorganisms that live in the intestines. and play a vital role in digestion, immunity, and many other body processes, thus maintaining gut health. It plays a vital role in the digestive process.

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