Dr. Saurabh Sethi, a gastroenterologist trained at AIIMS, Harvard, and Stanford, emphasizes the importance of stool color in assessing health. Normal stool is brown, indicating healthy digestion due to bile production. Green stool suggests rapid passage through the gut, while yellow or greasy stool may indicate fat absorption issues. Black stool can indicate potential internal bleeding, and bright red stool often relates to lower tract bleeding, commonly associated with hemorrhoids. While occasional changes in stool color can occur due to diet, persistent changes warrant attention. Dr. Sethi advises individuals to monitor their stool color as it can be an early indicator of underlying health issues. However, he stresses that this information is not a substitute for professional medical advice.