Bromelain is a general name for a family of enzymes extracted from the pineapple plant (ananas cosmosus). The enzymes are found throughout the pineapple. For commercial production however, it is extracted from the stem of the pineapple plant where most of the bromelain is concentrated.
Bromelain consists mostly of proteolytic enzymes which digest protein. When Bromelain is taken with a meal, it helps with digestion. When taken on an empty stomach, it enters the blood and has beneficial anti-inflammatory activity in the body. Research indicates that Bromelain's anti-inflammatory activity is due not only to its proteolytic enzymes but also to various other constituents in the pineapple.
Bromelain's anti-inflammatory activity appears to occur in a variety of ways. It is believed that bromelain inhibits the formation of thromboxanes, substances that cause joint soreness and stiffness. Bromelain's ability to help control run-away inflammation in the body has broad health benefits.
The strength or activity level of bromelain is usually measured in GDU (gelatin digesting units) per gram. Gelatin is protein. GDU per gram is a measure of how much protein a gram of bromelain can digest.
In order to understand the label of a product containing bromelain, you need to look at the GDU content per serving. It doesn't matter what the GDU per gram is. The only thing that matters is how much GDU you get in a serving of the product.
For example, if the bromelain in the product is 2,000 GDU per gram, and there is 100 mg (1/0th of a gram) of bromelain in a serving, then the amount of GDU you get per serving is calculated as 2,000 x 1/10th = 200 GDU per serving. This is important to understand because many products contain small amounts of 2,000 GDU or 2,400 GDU bromelain and you might think you are getting a lot but you actually get very little GDU per serving. Responsible manufactures should include the GDU per serving on the label. Otherwise you should calculate it as shown here.
For anti-inflammatory purposes, it is best to take bromelain on an empty stomach so it doesn't get used up digesting protein from food you ate. However, if the GDU per serving is high enough, it won't all get used in digestion and there will still be some left over to get absorbed into the blood.
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