Lipases are one of three categories of enzymes manufactured by the pancreas. The pancreas also secretes the hormones insulin and glucagon, which are needed to metabolize sugar, into the bloodstream. The other two enzymes include amylases, which break starch molecules into more simple sugars, and proteases, which break protein molecules into single amino acids. The most common dietary fats, triglycerides, comprise 95% of all ingested fats and are made up of a glycerol molecule combined with three fatty acid molecules. The lipases aid the digestion of fats by hydrolyzing the glycerol linkage within the chain to create more assimilable free fatty acids and monoglycerides. These components are then transported in the body by lipoproteins. Pancreatic lipase and bile salts are required for intestinal digestion and absorption.

This enzyme is manufactured by the pancreas. It does not come from diet, but may be supplemented by animal enzymes.

Gastric and pharyngeal (salivary) lipases are different from pancreatic lipase. They have lower molecular weights, a lower optimum pH (4 to 6 vs. 6 to 8), and a greater stability at pH 3. Gastric lipase is produced in the stomach and cleaves triglycerides at Sn-3 position within the stomach and duodenum. Pharyngeal lipase is produced in the oral cavity, also cleaving triglycerides at Sn-3 position within the mouth, esophagus, and stomach. Pancreatic lipase is produced in the pancreas, splitting Sn-1 and Sn-3 positions within the duodenum.

These lipases are important in the hydrolysis of triglycerides in milk during infancy, when the secretion of pancreatic lipase is not fully developed. In adults, as much as 10% to 15% of ingested fat may be partially hydrolyzed in the stomach.

Hepatic lipase has also been shown to impact aspects of blood lipid metabolism. It facilitates the clearance of potentially atherogenic lipoproteins by the liver and impacts the levels of the protective high-density lipoproteins.

Lipase tablets are available in units of 6,000 LU, and 1 to 2 capsules are recommended daily, to be taken before meals.

Tablets or capsules of pancreatic enzyme extracts with meals can be used to treat impaired digestion, malabsorption, and subsequent nutrient deficiencies. Some consider pancreatic enzymes of value in treating autoimmune disorders, inflammatory diseases, and food allergies. They have been most studied in treating early diagnosed celiac disease by enhancing the benefit of a gluten-free diet.

A reduction in lipase activity is unlikely to induce malabsorption in an adult, because pancreatic lipase is usually secreted in abundant amounts. Deficiency of pancreatic lipase is of clinical significance only when its secretion is below 10% to 15% of normal levels.

Recommended treatment with lipase to aid fat digestion is 1 to 2 capsules of 6,000 LU tid before meals. Lipase can also be found combined with protease and amylase.

None reported

Lipase and other pancreatic enzyme supplements are not associated with side effects.

Orlistat inhibits pancreatic and gastric lipases, preventing fats from being hydrolyzed into absorbable fatty acids (Heck et al. 2000).

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Heck AM, Yanovski JA, Calis KA. Orlistat, A new lipase inhibitor for the management of obesity. Pharmacother. 2000;20(3):270-279.

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Murray MT. Encyclopedia of Nutritional Supplements. Rocklin, Calif: Prima Publishing; 1986.

Shils ME, Olson JA, Shike M, eds. Modern Nutrition in Health and Disease. 8th ed. Philadelphia, Pa.: Lea & Febiger; 1994