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 some benefits in the face of risks of cancer and of risks of 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.
The interest of broccoli, and more specifically its active ingredient, sulforaphane, has been shown in nutritional prevention and nutritional therapy thanks to its antioxidant, anti-inflammatory and cell protection activities.
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.
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