Broccoli is an amazingly healthy vegetable and, as I have indicated in previous posts , contains the cancer-fighting (including breast cancer) chemicals sulphoraphane and indole-3-carbinol. However, a recent study suggests that the form of broccoli we eat and the way it is cooked makes an impact on the health benefits we receive from eating broccoli.
In a forthcoming article from the journal Nutrition and Cancer, researchers examined the differences in sulforaphane availability between broccoli sprouts and a broccoli powder. The broccoli powder, like many broccoli supplements, was rich in glucoraphanin, the plant chemical that is converted to sulforaphane, but lacked myrosinase, the enzyme needed for this conversion. Broccoli sprouts on the other hand are rich in this sulforaphane-producing enzyme. The breast cancer researchers asked 4 human volunteers to consume 4 meals at different times. The meals consisted of (1) dry cereal + yogurt, (2) dry cereal + yogurt + 2 grams broccol sprouts, (3) dry cereal + yogurt + 2 grams broccoli powder, and (4) dry cereal + yogurt + 2 grams broccoli sprouts + 2 grams broccoli powder. Blood and urine samples were collected after each meal and measure for sulforaphane. The breast cancer investigators reported
Sulforaphane levels were substantially higher after consumption of broccoli sprouts and after consumption of the combination of broccoli sprouts plus broccoli powder.
Broccoli sprouts enhanced the sulforaphane availability from broccoli powder.
This is a fascinating, though small, study that suggests not all broccoli products are the same when it comes to the health benefits of broccoli. While broccoli powder supplements can be rich in the sulforaphane precurser, the lack of the enzyme needed for its conversion reduces the potential health benefits of the broccoli powder. On the other hand, broccoli products that contain the myrosinase enzyme make the sulforaphane more available both in the product itself and in products like the broccoli powder that contain the sulforaphane precursor. However, this enzyme is destroyed by over-cooking, so lightly steaming one's broccoli provides a better opportunity to obtain its breast cancer-fighting benefits.