Active Ingredient in Broccoli
Enhanced with Added Selenium
~ April 2003 No.164 ~
Although it is often the brunt of jokes, broccoli has long been considered a vegetable that has special health promoting properties. It is now acknowledged that broccoli contains sulforaphane a chemical that has been shown to have cancer prevention properties.
Recent research carried out at the Institute of Food Research in Britain indicates that the beneficial properties of broccoli can be enhanced when selenium is also a part of the diet. Selenium is involved in many metabolic pathways and has also been shown to help in the prevention of cancer.
The selenium and the sulporaphane are working in synergy and, as is the case in many biological systems, one plus one does not equal two. That is, although both sulforaphane and selenium have beneficial effects alone, when they are combined it is reported that their cancer fighting properties are increased thirteen fold!
Sulforaphane, or more precisely 4-methylsulphinylbutyl isothiocyanate, is a sulfur containing compound that is a member of the group of compounds called isothiocyanate. Sulforaphane and other isothiocyanates have a chemical structure that makes them antioxidants. They are also potent stimulators of natural detoxifying enzymes in the body.
Sulforaphane is found in broccoli and other cruciferous vegetables such as cauliflower, cabbage, and kale, but the concentration can be variable. Isothiocyantes are produced by plants as natural insecticides and it has been found that broccoli sprouts contain anywhere from 30 to 50 times the concentration of protective chemicals that are found in mature broccoli plants.
It is not clear how the selenium adds to the potency of the sulforaphane, and so far experiments have only been done in experimental animals and with living cells to study how these two compounds affect enzymes that affect the onset and progression of cancer.
Selenium is a trace mineral which can be found in such foods as nuts, poultry eggs and mushrooms. Recently concern has been expressed particularly in Britain about the fact that the amount of selenium in British diets is about half of what it was 20 years ago.
Once again it appears that compounds that are found in very minute quantities in our foods may have major impacts on our health. A varied diet will provide a wide range of compounds that alone, or together, will improve our health.
- Zhang J, Svehlikova V V, Bao Y, Howie AF, Beckett GJ, Williamson G. 2003. Synergy between sulforaphane and selenium in the induction of thioredoxin reductase 1 requires both transcriptional and translational modulation. Carcinogenesis Mar;24(3):497-503
November 27 2015