Brief Answer:
there are many causes few important are as follows

Detailed Answer:
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I have gone through your question and I understood your problem.
I will explain you yhe causes in detail . Please note them carefully.

Digestion Problems

Fat digestion primarily depends on the action of pancreatic lipase although other fat-hydrolyzing digestive enzymes are also responsible to a lesser extent for fat digestion. Some of the conditions that may result in a disruption in the digestion of fats includes :

Pancreatitis (acute or chronic)
Pancreatic cancer
Other causes of pancreatic enzyme deficiency (exocrine insufficiency)
Gallstones, particularly bile duct stones
Primary sclerosing cholangitis
Zollinger-Ellison syndrome
Absorption Problems

Malabsorption syndromes are often characterized by steatorrhea. The causative conditions affect the absorption of fats through the intestinal lining and transport of fats through the lacteals. The formation of micelles is impaired with small bowel bacterial overgrowth, which is necessary for the absorption of fats into the epithelial cells lining the small intestine.

Celiac disease
Inflammatory bowel disease, particularly Crohn’s disease
Small bowel bacterial overgrowth
Abetalipoproteinemia
Whipple’s disease
Excessive use of slimming tablets containing orlistat
Rapid Gut Transit Time

The transit of chyme through the gut is carefully regulated in order to ensure there is sufficient time for the digestive enzymes to act on food and absorb through the intestinal lining. Any increase in the transit time may affect the digestion and absorption of nutrients, including fats.

Diarrhea
Possibly irritable bowel syndrome (diarrhea-predominant IBS)
Short bowel syndrome
Excessive use of laxatives

I hope my answer was helpful for you . Dont forget to close the discussion.Thank you.
DR . XXXXXXX HASABE

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