Kale is a member of the brassica family of vegetables. They are not only packed with health-boosting vitamins and minerals but are full of anti-carcinogenic phytonutrients, mostly in the form of the organo-sulphur compounds that give them their slightly bitter taste.

Kale’s sulphurophane, for example, interferes directly with tumour growth, as well as stimulating the body’s own defences against disease to create an antioxidant effect that lasts long after the kale has been eaten. Recent research has found that sulphurophane can disrupt the growth of breast cancer cells, even at the later stages, while an epidemiological study from China found that women who eat more brassicas, such as kale, have significantly reduced risks of breast cancer.

 

Kale has the highest levels of the carotenoids lutein and beta-carotene. Along with vitamin A and its beta-carotene precursor (which the body converts to vitamin A), good dietary intakes of lutein and zeaxanthin are vital for eye health. They are thought to act as filters in the eye, protecting against damaging ultraviolet light, and also as antioxidants that quench similarly damaging free radicals.

 

Epidemiological studies suggest that an increased consumption of the latter two nutrients is associated with a reduced risk for age-related macular degeneration, while another important study found that people who had the highest dietary intake of lutein-zeaxanthin had half the risk of cataracts as those with the lowest. Diets rich in carotenoids are also linked to lower rates of heart disease, while lutein protects against colon cancer.

 

Just 100g of kale provides 769mcg of vitamin A – that’s 110% of a man’s and 128% of a woman’s RDA – and very high levels of beta-carotene, which in the diet are linked to a reduced risk for heart disease. Kale can protect your heart in other ways, too: there are 120mcg of vitamin C per 100g of kale, providing an incredible 300% of your RDA. Apart from playing an important role in immunity and a healthy nervous system, this antioxidant vitamin is known to protect ‘bad’ LDL cholesterol from the oxidative damage by free radicals that can lead to cardiovascular disease. Kale is also high in fibre (2g/100g – 11% of RDA), and fibre-rich diets have been shown to lower the risks of heart disease by up to 12% and potassium (447mg/100g – 13% of RDA), which can help to lower blood pressure, thus reducing the risk of strokes.

 

Epidemiological studies suggest that diets rich in vitamin-C foods such as kale may protect against inflammatory conditions, such as rheumatoid arthritis. These greens also supply you with lots of omega-3 essential fatty acids, which can also protect against arthritis and rheumatism, as well as reduce the risk of strokes and heart attacks.

 

 

Last month’s IN THE NEWS highlighted a study published in the British Medical Journal Online First which suggested that those who eat quickly treble their risk of being overweight. Scientists involved in the study believe that the modern manner of eating on the go – and until absolutely full – is a significant factor in the current obesity epidemic because it overrides signals in the brain which normally encourage a little more self control. Now a study of British youngsters by Cancer Research UK, published in the American Journal of Clinical Nutrition suggests that teaching children to savour their food will not only help them manage their weight but also help combat cancer.

In the study scientists set about videoing more than 120 sets of twins between the ages of 10 and 12 as they ate sandwiches and fruit salad. They worked out how many bites a minute the children took and compared this with their weight. Fastest eaters were the overweight children, at 4.3 bites a minute; next came those on the heavy side of normal with 4.1 bites a minute. The thinnest youngsters took only 3.8 bites a minute. Although the researchers acknowledged that genes influence our eating rates they came to the conclusion that the faster children eat the more overweight they tend to be and the higher the risk of cancer. As obesity raises the risk of at least five forms of cancer, something as simple as teaching children to eat slowly could have a huge impact on public health.

 

Great dietary gurus of centuries ago stressed the importance of eating slowly and chewing food for a long time and as this study makes clear, this message is even more important today not just for busy adults who bolt down their food, but also for children.

The humble tomato has been at the centre of a whirlwind of scientific activity for several years, mainly because of its high lycopene content. Lycopene, a carotenoid compound which is found in relatively few foods, gives tomatoes their deep red colour and is a potent antioxidant which can protect cells and DNA from free-radical damage. Significantly, cooked tomato products are even higher in lycopene than the raw fruit – 100g of canned tomato paste, for example, contains an astonishing 28,764mcg, which is more than any other food tested so far.

The latest research shows that the higher the levels of lycopene in the bloodstream the lower is the risk of cardiovascular disease and cancer, including rectal, pancreatic and ovarian. In one study eating lycopene-rich foods such as tomatoes was found to reduce the risk of developing prostate cancer by up to 50 per cent, while another study showed that low levels of lycopene increased the risk of developing colorectal adenomas (a precursor for most colorectal cancers) by 230%.

 

Raw tomatoes are also a good source of lutein, which is important for eye health.  100g of tomatoes, which is about one small tomato, provides:

 

• 7.5% of our daily requirement for folate, which reduces the risk of coronary heart disease by lowering blood levels of homocysteine. (NB it also protects a developing foetus from neural tube defects such as spina bifida)

• 7% for fibre.  Diets high in fibre can prevent heart disease, as well as constipation and colon diseases such as diverticulitis and cancer

• 7% for potassium which lowers blood pressure, reducing the risk of strokes in the long term

• 32% for vitamin C a powerful antioxidant which prevents oxidation of ‘bad’ LDL cholesterol – a process that enables LDL to stick to artery walls, where it can eventually cause blockages, resulting in strokes, angina and heart attacks. 

 

Diabetics and people with insulin resistance could benefit from eating tomatoes. They are high in chromium which is important for regulating blood sugar levels – people with type 2 diabetes, for example, have lower blood levels of chromium than those without the condition.