Eat Broccoli to Reap Phytochemical Benefits

CORVALLIS, Ore.The research is new, but the message is the same: eat your vegetables. Scientists from Linus Pauling Institute at Oregon State University found that eating broccoli and other cruciferous vegetables has more health benefits than taking a supplement containing similar healthy compounds.

The issue of whether important nutrients can be obtained through whole foods or with supplements is never simple," said Emily Ho, an OSU associate professor in the OSU School of Biological and Population Health Sciences, and principal investigator with the Linus Pauling Institute. Some vitamins and nutrients, like the folic acid often recommended for pregnant women, are actually better-absorbed as a supplement than through food. But the particular compounds that we believe give broccoli and related vegetables their health value need to come from the complete food."

The researchers found that the enzyme myrosinase is missing from most supplement forms of glucosinolates, a phytochemical in cruciferous vegetables that is linked with a reduced risk of developing prostate, breast, lung and colorectal cancer. The myrosinase found in broccoli and similar vegetables help break the glucosinolates into sulforaphane and erucin. Sulforaphane, in particular, may help to detoxify carcinogens, and also activate tumor suppressor genes so they can perform their proper function. The researchers found that most supplements designed to provide glucosinolates have myrosinase enzyme inactivated, so the sulforaphane is not released as efficiently. There are a few supplements available with active myrosinase, and whose function more closely resembles that of the whole food, but they are still being tested and not widely available, Ho said.

The study, published in the Journal of Agricultural and Food Chemistry, also found that overcooking broccoli also squashes its nutritional power.