And lipase is important for taking fat and putting it in a form that can be absorbed.

NPR: Slate's Medical Examiner: Xenical OTC

So if lipase is inactivated then the fat can't be absorbed and it passes right through us.

NPR: Slate's Medical Examiner: Xenical OTC

Dr. SPIESEL: You swallow it and it enters the intestinal contents and it blocks the activity of an enzyme called lipase.

NPR: Slate's Medical Examiner: Xenical OTC

Researchers noted that prolonged sitting can cause a 90 percent reduction in a heart-healthy enzyme, lipoprotein lipase, which could explain the results.

FORBES: Four hours on your computer doubles risk of heart disease

Case in point: the familial disorder known as lipoprotein lipase (LPL) deficiency affecting 1 to 2 persons per million, which is caused by mutations in the gene that codes the LPL enzyme.

FORBES: Europe Takes The Lead Toward Approval Of First Gene Therapy Drug

Glybera is used to treat lipoprotein lipase deficiency.

BBC: Gene therapy: Glybera approved by European Commission