Broccoli - a bouquet of health

What are cruciferous vegetables?

The family of cruciferous vegetables includes over 2000 species divided into 230 types.

These include broccoli, green and red cabbage, and kale, cauliflower, Chinese cabbage, Brussels sprouts, kohlrabi, bokchoi, turnips, swedes and even radish, cress, rocket and horseradish.

Cruciferous vegetables contain fibres, folates, carotenoids (including beta-carotene, lutein and zeaxanthin), selenium and a high amount of vitamin C. Broccoli is also rich in vitamins K and B9.

Cruciferous vegetables are recognized for providing benefits that can reduce the risks of cancer and cardio-vascular disease.

The healthy properties of cruciferous vegetables

Studies have shown that cruciferae such as broccoli provide factors that protect against several kinds of cancer. It has been shown that eating three to five servings of cruciferous vegetables per week leads to significant protection.

According to research, eating broccoli at least once a week may reduce occurrence of colorectal, stomach, lung or prostate cancer. It may even lessen the chances of breast cancer in premenopausal women.

The protective properties of cruciferous vegetables, especially broccoli, are believed to come from sulfur compounds called glucosinolates, and more specifically from their hydrolysis products, isothiocyanates, including sulforaphane. 

Why broccoli is of interest

For the same amount, broccoli contains more nutrients than any other vegetable.

A low energy food, (thirty four kilocalories per hundred grams), poor in carbohydrates and rich in fibres, it is recommended for diabetics and for those trying to cut down on their food intake.

Broccoli, and more specifically its active ingredient, sulforaphane, has been shown to be good both for nutritional prevention and for nutritional therapy, as it helps slow down the cell cycle and activates the death of cancer cells.

The levels of sulforaphane vary enormously depending on the species and variety of cabbage. Broccoli is known to be the richest in glucoraphanin, which is converted into sulforaphane, the active molecule of broccoli, by an enzyme. Its level of sulforaphane is in the order of 1 to 100mg/100g.

It is better to eat broccoli raw or very lightly cooked because over-cooking destroys its nutritional qualities and reduces the creation of sulforaphane.

References
  • Cruciferous Vegetables and Human Cancer Risk: Epidemiologic Evidence and Mechanistic Basis.Higdon J. V., Delage B., Williams D. E., Dashwood R. H.
  • Veggies may cut by half risk of prostate cancer, Seattle Times, Tuesday January 4, 2000, page 1. Les recherches originales étant publiées dans The Journal of National Cancer Institute, January 5, 2000. Kristal A., Cohen J., Standford J.
  • A prospective study of cruciferous vegetables and prostate cancer. Cancer Epidemiol Biomarkers Prev. 2003 Dec; 12(12):1403-9. Giovannucci E, Rimm EB, Liu Y, Stampfer MJ, Willett WC.
  • Brassica vegetables and cancer prevention. Epidemiology and mechanisms. Adv. Exp. Med. Biol., 472: 159-168, 1999. Van Poppel G., Verhoeven D. T., Verhagen H., Goldbohm R. A.
  • Légumes et chimio-prévention anti-cancer: le système glucosinolate / myrosinase. ICOA – UMR 6005, Université d’Orléans, BP 6759, 45067 Orléans Cedex 2. A Farinha, P Rollin, A Tatibouët.