Which organ kills bacteria in the human body?

The stomach is the organ that primarily kills bacteria in the human body during digestion. It secretes hydrochloric acid (HCl), which creates a highly acidic environment.

This acidic condition helps destroy many harmful microorganisms that enter the body along with food and water. It also prevents infections and protects the digestive system.

In addition to killing bacteria, hydrochloric acid activates digestive enzymes like pepsin, which aid in protein digestion.

Thus, the stomach plays a dual role in digestion and defense by eliminating harmful bacteria.