Does this stool coloration indicate anything bad?

I put this under the diarrhea forum because I really don't know what it is, but I'm usually constipated, have been since age 11. (I'm now a 19 year old female with no noted health problems other than OCD).  My stools are usually hard and brown.  Recently, within the past few days, I've noticed that my stools are softer (one day it was like diarrhea, then a few days later it was just a softer stool) but they are lighter, not yellow or clay-colored, but sort of like baby poop (light brown, yellow/green).  I'm not an intrevenous drug user, and I haven't had unprotected sex with anyone other than a tested long-term partner, months ago.  I don't know what is wrong with me!  I have no other weird symptoms.  I do eat a lot of sushi and Indian food.  What do you think is causing this stool coloration and should I be concerned? I do not have a fever or anything else that would indicate a viral infection...so confused!  I asked my mom and she says it happens to her on occasion too, a possible sign of dehydration (It's true that I do not drink enough water)

[Kevin Pho, MD]

Lighter stools can be due to biliary obstruction.  Green stools usually does not point to a specific disease, but irritable bowel syndrome or malabsorption can cause leafy vegetables to present as green stools.  

If the stools continue to get lighter, obtaining liver function tests and an ultrasound would be the suggested approach to discuss with your personal physician.

This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.

Kevin, M.D.
www.kevinmd.com