- Discussion:
    - following a Polya or Billroth II gastrectomy, osteomalacia develops that was quite subtle and only revealed itself by increasing muscle 
           weakness or a pathological fracture;
    - abnormal fat metabolism, usually associated w/ failure of emulsifying action of bile salts or presence of free fat in intestinal tract;
    - diffuse injury to the wall of small bowel, as occurs with inflammatory processes such as celiac disease, Crohn disease, or disorders 
           associated with a short loop (shunts or fistulae) or rapid transit (gluten-sensitive enteropathy and other sprue-like syndromes);
    - absorption characteristics:
         - approximately 20% of oral calcium is absorbed by the gut under normal conditions;
         - requires physiologic gastric acidity and normal bowel and pancreatic funciton;
    - substances that interfere w/ calcium absorption:
           - excessive fatty acids bind calcium and prevent absorption;
           - phytic acids (found in wheat and tea);
           - excessive phosphorous (as in soft drinks) binds Ca and prevents absorption;
           - oxylates (found in spinach);
           - excessive phosphorous (as in soft drinks) binds Ca and prevents absorption;
                 - excessive fatty acids bind calcium and prevent absorption;
                 - phytic acids (found in wheat and tea)