Bowel cancer grows quietly along the colon or rectum. Early signs look like everyday tummy troubles, so key is noticing when “normal” changes last too long.

Blood in the toilet is the red flag. It can be bright red on the paper, dark mixed with stool, or cause the water to look pink.

Stool shape changes. Pencil-thin or ribbon-like stools that last more than a few weeks are common.

Belly cramps feel like gas pains that don’t fade. They come and go but slowly get worse.

Bowel habits flip. You swing between constipation and diarrhea, or feel you still need to go right after finishing.

Weight drops without trying. Clothes feel looser even though appetite is the same.

Late signs include a hard lump you can feel in the belly, yellow skin (jaundice), or vomiting—an alarm the cancer has spread.