Brief Answer:
might be biliary obstruction, malabsorption, diarrhea etc.

Detailed Answer:
Hello.
Welcome to HCM.
This is Dr. Swarnava Dattagupta answering your query.

I understand your concern.
Your question is somewhat nonspecific so i am giving you the various reasons of light coloured stools.
Light coloured stool can be pale or clay coloured which is found in bile obstruction due to obstructive jaundice, can be stones or carcinoma.
It can also be found in celiac disease or malabsorption syndrome where there is excess undigested fat giving it a light yellow frothy feel. Similarly it can occur in chronic pancreatitis, pancreatic carcinoma etc.
In diarrhea due to various reasons, the normal golden brown colour of stool is also faded due to presence of excess water and presents as light coloured stool. It can be found in stomach infection leading to diarrhea.

Hope this was helpful.
Consult me for further queries.
Regards.

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Brief Answer:
All can present with tiredness

Detailed Answer:
Hello again.
Almost all the disorders mentioned above can lead to tiredness. Diarrhea, carcinoma and malabsorption are more common to cause tiredness.
Avocado contains lots of fat hence lots of calories. Some of it gets excreted with stool and excess fat in stool can cause greasy light coloured stool. It is a possibility.

Hope this helps.
Regards.

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