What are phytonutrients?

Phytonutrient literally means ‘plant nutrient’. These nutrients are naturally occurring compounds that contribute to the flavour, colour and disease resistance in plants and they are present in all plant foods - vegetables, fruit, whole grains and legumes (lentils, peas and beans). Phytonutrients also have properties that are beneficial to the health of humans, for example many of them act as antioxidants and therefore protect the body from the ravages of excess free radical activity.

Free radical

An atom or a group of atoms possessing an unpaired electron. The presence of the unpaired electron means that free radicals are highly reactive chemicals always ready to react with cell components extracting from them the missing electron leading to damage. Free radicals occur as a part of normal cell metabolism but their numbers in the organism greatly increase when it is exposed to damaging environmental influences. Free radicals have been implicated in accelerated ageing and the development of degenerative diseases such as cancer. One of the key ways in which the body protects itself against excess free radical activity is through the use of antioxidants.

Examples of anti-cancer phytonutrients

Carotenoids

e.g. alpha-carotene, beta-carotene, lutein, lycopene

• Some have vitamin A activity e.g alpha-carotene, beta-carotene
• Antioxidant activity
• Enhance immune function   

Orange/red vegetables and fruit and dark green vegetables e.g. carrots, squash, red peppers, sweet potatoes, tomatoes, watermelon, mango, apricots, kale, spinach, broccoli

Curcumin   

• Antioxidant activity
• Enhance detoxification
• Anti-inflammatory   

Curcumin is the main active ingredient in the curry spice turmeric

Glucosinolates, indoles and isothiocyanates   

• Block cancer-causing compounds from damaging cells
• Enhance detoxification

Cruciferous vegetables e.g. cabbage, broccoli, brussel sprouts, Swiss chard, cauliflower, kale, watercress, mustard greens

Flavonoids

e.g. anthocyanins, quercitin, rutin, bioflavonoids   

• Antioxidant activity
• Enhance immune function and protect against allergies
• Anti-inflammatory
• Support collagen production
• Inhibit oestrogen activity   

Richly coloured vegetables and fruit particularly dark green vegetables, peppers, tomatoes, beetroot, red grapes, berries

Isoflavones

e.g. genistein, diadzein   

• Modulate oestrogen activity
• Antioxidant activity   

Soya and other legumes

Lignans   

• Modulate oestrogen activity
• Enhance immune function
• Antioxidant activity
• Anti-bacterial, anti-viral, anti-fungal   

Flaxseed and flaxseed oil, whole grains, nuts, seeds

Limonoids   

• Enhance detoxification   

Citrus fruits, celery

Polyphenols

e.g. catechins   

• Antioxidant activity
• Modulate hormone activity   

Tea (green, black, white), dark chocolate, red wine

Phytosterols   

• Modulate hormone activity
• Regulate cholesterol levels   

Nuts, seeds

Organic acids

e.g. ellagic acid   

• Antioxidant activity
• Enhance detoxification
• Anti-inflammatory   

Raspberries, strawberries, apples, grapes, currants

Consuming a diet rich in phytonutrients >>