In IBS you need to follow FODMAPs diet under supervision to first understand which food item is responsible for your symptoms.
Once identified that food item has to be completely eliminated from your diet and all the other food items restricted by FODMAPs diet are to reintroduced carefully.
Long standing diarrhoea might be an indication that you are constantly eating a food item which is not getting digested at all. Thus worsening your symptoms.
Next Steps
Stress management and sleep hygiene are extremely important as far as IBS management is concerned.
If possible start doing yoga under guidance to improve digestion and manage stress
Health Tips
Since you are having diarrhoea I would advise you to increase your fluid intake and to strictly stop eating outside food.
Hope this helps!
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