What causes diarrhea every time after eating a meal?

Eating a meal followed by one episode of diarrhea is usually caused by indigestion, irritable bowel syndrome (IBS), gastroenteritis, or other similar conditions.

1. Indigestion

If eating habits are irregular, with frequent overeating, or if there is long-term consumption of spicy, stimulating, greasy, raw, or cold foods, gastrointestinal motility may become abnormal, leading to indigestion. This can result in the phenomenon of having diarrhea after each meal.

2. Irritable Bowel Syndrome (IBS)

Patients with irritable bowel syndrome typically have a significantly lower pain threshold for colorectal distension compared to healthy individuals. After eating, this may trigger an excessive motor response, causing diarrhea following each meal. This is often accompanied by symptoms such as abdominal pain.

3. Gastroenteritis

Gastroenteritis is usually caused by acute or chronic inflammation of the gastric or intestinal mucosa due to various factors. This inflammation can impair gastrointestinal digestive function, potentially leading to diarrhea after eating. Additional symptoms may include abdominal pain, nausea, vomiting, bloating, and heartburn.