Welcome to HCM
You are having a problem of chronic diarrhoea if it is more than 4 weeks,which could have many causes we need to look in simple causes to some rare one if there is problem which is persisting long enough and there is weight loss or signs of any kind of deficiency is noticed or detected one must rule out organic pathology.
common one are Infective,Inflamatory Bowel disease,Malabsorption
Syndromes,Alcohol induced,or laxative use?.Any kind of endocrinal disease, If we rule out significant organic disease it could be even Irritable Bowel syndrome
One should keep a Possibility of Food Allergy?
Consult a Gastroenterologist
and investigate yourself with Routine examination of Stool, Acid fast stain, for Giardia ,Complete Blood count
,Blood Biochemistry,T3T4 TSH,
A Gastroscopy, Ultrasonography
with if any furthur test is required and suggested by Your Doctor.
Once cause is detected treatment would be simple.
One more aspect Prevention:
Uncontaminated drinking water and ?proper sewage disposal .
Everybody, especially food handlers, should maintain strict personal hygiene.
Travellers should refrain from drinking unbottled water and other drinks and should not eat raw vegetables, raw meat or sea food