Bromelain is a general name for a family of sulfhydryl-containing, proteolytic enzymes obtained from the pineapple plant. It appears a great deal of the physiological activity of bromelain cannot be accounted for by its large proteolytic content, but that its beneficial effects are due to multiple factors, some of which are as yet unknown.
A variety of designations have been used to indicate the activity of bromelain. Rorer units (RU), gelatin dissolving units (GDU), and milk clotting units (MCU) are the most commonly used measures of activity. One gram of bromelain standardized to 2,000 MCU would be approximately equal to 1gm with 1,200 GDU of activity or 8gm with 100,000 RU of activity.
Bromelain is absorbed intact through the gastrointestinal tract, with the highest concentration of bromelain being found in the blood one hour after administration. However, its proteolytic activity is rapidly deactivated.
In human clinical tests, side-effects are generally not observed. However, there is always the possibility that someone may develop an allergy to bromelain. Possible hidden sources of bromelain include meat tenderizers and beer, where it is used in the clarification process.
Bromelain has shown therapeutic benefits in doses as small as 160mg per day. For most conditions, the best results occur at doses of 750-1000mg per day. Most research on bromelain has been done utilizing four divided daily doses, usually between meals.