Small Intestinal Bacterial Overgrowth (SIBO) occurs when excessive bacteria accumulate in the small intestine, disrupting digestion and absorption. Unlike the large intestine, the small intestine should have relatively low bacterial levels. Overgrowth can lead to bloating, abdominal pain, diarrhoea, constipation, and nutrient deficiencies, particularly vitamin B12 and iron. SIBO often develops due to impaired gut motility, low stomach acid, structural abnormalities, or prior infections. Left untreated, it can worsen gut inflammation and systemic symptoms. Treatment typically involves targeted antibiotics or herbal antimicrobials, dietary strategies, and functional approaches to restore gut balance and prevent recurrence.