Brief Answer:
common following gut surgeries.

Detailed Answer:
Hi XXXX
Hope you are in god health.
White stools are seen in many conditions related to gastro intestial tract including gall bladder diseases, bile stones, pancreatic diseases etc.
In your case, as you have undergone cholecystectomy, intestinal resection for diverticulitis and regional enteritis, you will have improper fat digestion and absorption as bile flow and release will be untimely with the food you take. This results in fat malabsorption cahracterized by loose stools, pale stools and depending on the mucus content, may look white also. i believe, your high protein and fat diet is making it worse. So, at the present, there is no need to worry, a little reduction in fat diet might help..
If you also have jaundice along with pale stools, you should consider bile duct stones or pneumobilia which can often complicate lately gall bladder surgeries, for which you need a surgeon's consultation.
hope i am clear.

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