Does green stool indicate illness, or can food cause it?
Green stool can follow green vegetables, food colouring, iron or faster intestinal transit during diarrhoea. Colour alone does not identify a disease. Duration and accompanying pain, fever, diarrhoea or dehydration matter more.
Details
Review recent changes
Consider foods, supplements and medicines taken before the colour changed. A brief change without other symptoms can often be observed. Do not stop prescribed iron solely because of colour; discuss troublesome symptoms with a clinician or pharmacist.
If diarrhoea accompanies it
Replace fluids according to your health needs. Seek advice earlier for young children, older people and those with reduced immunity. Reduced urine, lethargy or inability to drink warrants prompt assessment; avoid self-prescribing antibiotics.
Other warning signs
Persistent unexplained changes or weight loss deserve review. Black tarry stool or red blood, particularly with dizziness or severe pain, differs from green stool and may indicate bleeding requiring urgent care.
Related reading: When can yellow stool suggest poor fat absorption?.