Which enzyme in saliva begins lipid digestion, particularly in infants?

• A. Lingual lipase
• B. Salivary amylase
• C. Pepsinogen
• D. Pancreatic lipase

Answer: (A)

Lipids begin to be digested right in the mouth by a lipase found in saliva. This enzyme, produced by glands in the tongue, is lingual lipase. It starts breaking down triglycerides into diglycerides and fatty acids as you chew, which is especially important in infants because milk fat is a major part of their diet and pancreatic lipase activity is still maturing. Lingual lipase remains active in the stomach and contributes to fat digestion during early life, when the stomach’s environment is suitable for it. The other enzymes listed don’t perform this function in saliva: salivary amylase targets carbohydrates, pepsinogen is a stomach enzyme, and pancreatic lipase is produced by the pancreas and acts later in digestion.