Don't you just love vegetables? But do you know why they're so good for you? Here are a list of your top ten favourite picks. Find out what is available, what makes them healthy and the nutrition content of each one.
- 1. Asparagus
- 2. Tomato
- 3. Onion
What's available: asparagus comes in different sizes and colours, from thin green varieties to pale, fat stalks.
Healthy highlights: asparagus contains fructo-oligosaccharides (FOS), which promote the growth of 'good' bacteria in the gut. A study showed that volunteers taking a 4g daily supplement of FOS had an increased number of 'good' bacteria called bifidobacteria in their gut and reduced levels of enzymes that promote cancer-causing compounds. Asparagus also contains phytochemicals called saponins, which have anti-cancer properties, as well as cholesterol-lowering effects.
Nutritional content: asparagus is a good source of folate and vitamin E.
What's available: many varieties of fresh tomato are available these days - little cherry red, orange and yellow tomatoes, plum tomatoes, green tomatoes, beef tomatoes and vine-ripened ones.
Healthy highlights: tomatoes are excellent sources of lycopene especially ones that have been processed, for example, canned tomatoes, tomato ketchup, tomato soup. Lycopene is a powerful antioxidant. A large study in the US has shown that men who ate tomato products at least 10 times a week had a 35 per cent less risk of developing prostate cancer. Additionally, scientific studies have shown that lycopene is associated with a reduction in the risk of developing heart disease in men.
Nutritional content: high in vitamin C, calcium, iron and phosphorous.
What's available: there is a large array of different types of onions available, including red onions, Spanish onions, white onions, English brown onions, pickling onions and spring onions. Bulb onions are imported from many countries around the world including Spain, the Netherlands, Italy and Hungary.
Healthy highlights: onions are rich in flavonols called quercetin. Flavonols are potent antioxidants and studies in countries such as the USA, Finland and Greece have shown that quercetin has the ability to lower cholesterol as well as reducing the risk of heart disease. Onions contain high levels of compounds called allylic sulphides which have the ability to induce enzymes that detoxify cancer-causing agents. In traditional medicine, onions have been used for helping catarrh.
Nutritional content: onions are a good source of fibre and potassium.
- 4. Peppers
- 5. Spinach
- 6. Lettuce
- 7. Carrot
What's available: yellow, orange, red, white and green bell peppers are available all year round and are often used as salad vegetables or roasted in the oven.
Healthy highlights: peppers (particularly red and orange), are rich in phytochemicals called beta cryptoxanthin as well as beta carotene . Research has shown that people with high levels of beta cryptoxanthin have a reduced risk of angina. Peppers are also rich in capsaicin which has been shown to have anti-inflammatory effects as well as helping to stimulate digestion.
Nutritional content: peppers have a high vitamin-C content which enhances the effects of antioxidants.
What's available: most of the spinach sold in the shops is grown in this country and is available all year round. Young leaf spinach is excellent as salad leaves.
Healthy highlights: spinach contains a phytochemical called lutein. Research has shown that lutein, in combination with the carotenoid zeaxanthin, protects against age-related macular degeneration (ARMD). ARMD is the most common cause of blindness in the Western world. A study in the US has shown that eating lutein-rich foods such as spinach, may help reduce the risk of developing colon cancer. Spinach is also rich in folate which is needed to reduce the risk of developing neural tube defects in unborn babies. In traditional medicine, spinach was thought to be useful in treating constipation, high blood pressure and anaemia.
Nutritional content: spinach is an excellent source of carotenoids, lutein, iron, vitamin K, oxalic acid, folates and vitamin C. Potassium and magnesium are also present in significant amounts.
What's available: lettuce comes in a variety of colours, from the palest green Iceberg to the deepest brown Oak Leaf. They can be classified in three different types: round varieties, such as. Butterhead, Iceberg; long varieties, such as. Cos, Romaine, Little Gem; and loose-leaved types, such as. Oak leaf, Lollo Rosso, Red Lollo.
Healthy highlights: different types of lettuce contain different amounts of phytochemicals. For example, Lollo Rosso is rich in flavonols, quercetin and lutein, and in the flavonoid anthocyanin, whilst Cos Lettuce is an excellent source of zeaxanthin and lutein. Numerous studies have shown that quercetin and lutein can protect against cancer. A large study in the USA has shown that women who ate lettuce at least once a day had half the risk of breaking a hip than those who ate one or less portions of lettuce a week. In traditional medicine, lettuce is thought to have sedative effects, thus aiding a good night's sleep.
Nutritional content: lettuce is a good source of folate and potassium.
What's available: carrots are available all year round. New carrots need scrubbing, whilst main-crop carrots should be peeled. Different varieties include: Nantes, an early cropping carrot; Parisienne; Chantenay and Zino, which is excellent for juicing.
Healthy highlights: carrots contain a phytochemical called ? [beta?] carotene, which, besides being a powerful antioxidant, can also be converted into vitamin A in the body. Carrots can actually help you see in the dark, since a prolonged vitamin A deficiency can lead to night blindness. Carrots may also help reduce the risk of lung cancer. A long-term study in the US on female nurses has shown that those who ate at least five carrots a week had a 60 per cent lower risk of developing lung cancer than those who didn't eat any carrots.
Nutritional content: carrots are rich in vitamin C, fibre, and some trace minerals.
- 8. Aubergine
What's available: aubergines are available in different colours, shapes and sizes. Take your pick from deep purple cylindrical ones, small thin, paler purple ones streaked with creamy colour, to the small purple, yellow and green round varieties used in Asian curries.
Healthy highlights: aubergines contain anthocyanins, particularly nasuin, which are potent antioxidants. Nasuin extracted from aubergine skin has been shown in laboratory conditions to block the formation of free radicals. Free radicals are known to cause damage to cell membranes and cause oxidation of 'bad' LDL cholesterol, which can increase the risk of heart disease and strokes. In traditional medicine, aubergine has been used to treat cancer and measles.
Nutritional content: aubergines are a good source of folate, potassium and fibre.
- 9. Cabbage
- 10.Broccoli
What's available: Cabbage comes in numerous varieties, for example, winter cabbage such as red, white and Savoy; pointed cabbage, which tends to be dense and have firm leaves, whilst Chinese cabbage is leafier and less dense.
Healthy highlights: cabbage contains phytochemicals called indoles. Indoles have been shown to have anti-cancer properties. Research in animals and under laboratory conditions suggests that indoles may help fight cancer by stimulating the production of enzymes, which form part of the body's detoxifying systems.
Nutritional content: rich in fibre, vitamin C, beta carotene.
What's available: there are two types of broccoli that you can buy - calabrese, which has dense blue heads, and sprouting broccoli, which is leafier with smaller, looser purple heads. Calabrese is available all year round, whilst UK-grown sprouting broccoli is available from February to May.
Healthy highlights: broccoli contains the phytochemical sulphoraphane. Research has suggested that sulphoraphane has the ability to block cancer-causing agents by stimulating the production of enzymes which form part of the body's detoxifying system. Studies have shown that diets rich in cruciferous vegetables, such as broccoli, are linked with a reduced risk of bowel, stomach, breast, lung and kidney cancer.
Nutritional content: broccoli is an excellent source of vitamin C, calcium, folate, selenium and fibre.