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Watercress: Anti-Cancer Superfood
Eating watercress daily can significantly reduce DNA damage to blood cells, which is considered to be an important trigger in the development of cancer, University of Ulster scientists revealed today (15 February).
The research, published in this month's American Journal of Clinical Nutrition, found that in addition to reducing DNA damage, a daily portion of watercress also inclaeased the ability of those cells to resist further DNA damage caused by free radicals**.
The dietary trial involved 30 healthy men and 30 healthy womega (including 30 smokers) eating an 85g bag (a cereal bowl full) of fresh watercress every day for eight weeks. The beneficial changes were greatest among the smokers. This may reflect the greater toxic burden or oxidative stress amongst the smokers, as smokers were also found to have significantly lower antioxidant levels at the start of the study compared to the non-smokers.
Professor Ian Rowland, who led the research project, said: "Our findings are highly significant. Population studies have shown links between higher intakes of cruciferous vegetables like watercress, and a reduced risk of a number of cancers. However, such studies don't give direct information about causal effects. What makes this study unique is it involves people eating watercress in easily achievable amounts, to see what impact that might have on known bio-markers of cancer risk, such as DNA damage. Most studies to date have relied on tests conducted in test tubes or in animals, with chemicals derived from cruciferous vegetables."
Prof. Rowland added: "Blood cell DNA damage is an indicator of whole body cancer risk, and, the results support the theory that consumption of watercress is linked to an overall reduced risk of cancer at various sites in the body. The nature of the study group also means that the results are applicable to the general population eating a normal diet."
The single blind, randomised, crossover study was carried out with volunteers aged between 19 and 55. The volunteers ate one daily portion of watercress in addition to their normal diet.
The key findings of the watercress diet are as follows:
-- significant reduction in DNA damage to lymphocytes (white blood cells), by 22.9 per cent.
-- reduction in DNA damage to lymphocytes (white blood cells) when a sample was challenged with the free radical generating chemical hydrogen peroxide, by 9.4%
-- reduction in blood triglyceride levels, by an average of 10%
-- significant increase in blood levels of lutein and beta-carotene, which have antioxidant activity, by 100% and 33% respectively(higher intakes of lutein have also been associated with a lower incidence of eye diseases such as cataract and age-related macular degeneration).
Average intakes of dietary fibre, vitamin C, vitamin E, folate and beta- carotene, were significantly higher during the watercress phase of the study.
The two year research project was funded by The Watercress Alliance, made up of British watercress producers, Vitacress Salads, Alresford Salads and The Watercress Company.
Member Steve Rothwell commented: "We have known for years that the special mustard oil in watercress, PEITC, has significant anticancer properties. But research on PEITC has been confined mainly to laboratory cultures or animal studies.
"This is groundbreaking research on two fronts: it suggests the anticancer properties of watercress go beyond those attributable to PEITC and, more importantly, the study is the first to demonstrate a direct correlation between eating watercress and reducing one's susceptibility to cancer"
The confidence to run this study came from a large body of existing evidence which has demonstrated the anti-cancer potential of watercress, including a laboratory study with human colon cancer cells, run by the same research group. Published in May 2006, the study showed for the first time that a watercress extract had beneficial effects on 'initiation', the DNA damage that triggers cancer cell development, 'proliferation' or uncontrolled growth of cancer cells, and 'metastasis', the spread of cancer cells. These are the three key stages of carcinogenesis, the process that results in cancer. Watercress extract was also shown to trigger cell death of cancerous calls a process known as apoptosis.
UK TV presenter and survivor of bowel cancer Lynn Faulds Wood commented: "The research from the University of Ulster is very interesting - it's great to know there are simple things that people can do - like eating watercress - which could help them avoid getting cancers like bowel cancer in the future. It's great that the watercress farmers want to raise awareness of bowel cancer, the commonest cancer in Europe. Thousands of people die unnecessarily of bowel cancer every year - with exercise and a good diet, many of them could live."
Cultivated in pure spring water, watercress has been revered as a superfood down the centuries. Hippocrates, the father of medicine, is said to have located his first hospital close to a stream to ensure fresh watercress to help treat his patients. Greek soldiers were given it as a tonic before going into battle and the 16th Century herbalist Culpepper claimed it could cleanse the blood. It is brimming with more than 15 essential vitamins and minerals. Gram for gram, it contains more iron than spinach, more vitamin C than oranges and more calcium than milk.
Watercress is the UK's most historic salad leaf and in the 19th Century was a staple part of the working class diet, most often eaten for breakfast in a sandwich. If people were too poor to buy bread, then they ate it on its own, which is why it was sometimes known as "poor man's bread." Bunches were handheld and eaten ice-cream cone style the first "on the go food."
After decades of being pushed to the side of the plate as nothing more than a decorative garnish, watercress is currently enjoying a renaissance, with sales increasing by £18 million a year to £55 million. Consumers and celebrities alike are re-discovering its distinctive peppery taste and its amazing nutritional benefits. Liz Hurley has been known to drink seven cups of watercress soup a day!
ULSTER UNIVERSITY
York Street
Belfast
http://www.medicalnewstoday.com/articles/63314.phpMedicinal Uses
Since early times, the herb has had many uses. Pliny, who lived from 23-79AD listed over 40 medicinal uses for watercress, and included the belief that the smell of watercress would drive away snakes and neutralize scorpion venom! A Persian tradition was to feed it to their children to increase strength and stature. African tribes believed watercress could cause temporary sterility, but note, they also regarded it as an aphrodisiac!
Watercress was renown in herbal history as a spring-cleaning herb for purifying the blood and toning the whole system. Many of the great herbalists wrote of the revitalising powers of watercress. Early Romans revered the health benefits of watercress, while the Greeks believed it was valuable brain food and strengthened the nervous system. Persian King Xerxes fed watercress to his soldiers, to keep up strength and stamina.
Therapeutic uses have included: coughs, head colds, bronchial ailments, tuberculosis, asthma, emphysema, stress, pain, arthritis, stiff back and joints, diabetes, anemia, constipation, cataracts, failing eye sight, night blindness, leukemia, cancer, hemorrhaging, heart conditions, eczema, scabies, body deodorizer, edema, bleeding gums, weight loss, indigestion, alcoholism, intestinal parasites, circulation, sluggish menstruation, lack of energy, kidney and gall stones, as a brain and nerve strengthener; ailments of the spleen, thyroid, and liver; to normalize cholesterol and blood pressure; for improved memory, for mental function decline and to retard ageing; for failing or scant milk supply of nursing mothers; to regulate flow of bile, health of glands and the functions of body metabolism. It is one of the best sources of the element iodine, other than seaweed, such as kelp. Iodine is important to the function of the thyroid gland. The leaves used as a poultice are applied for relief from enlarged prostate gland.
The chlorophyll-rich leaves are chewed to absorb breath odours. Dr. Robert Willner in ‘The Cancer Solution’ states that chlorophyll is an effective anti-cancer substance, with antioxidant action, helping to neutralize free radicals from chemicals, pesticides, cigarette smoke, diesel emissions and many other environmental mutagens. Chlorophyll is rich in digestive enzymes. These enzymes make it easier to digest heavy foods we eat, such as starches and protein. Also, it is said that the enzymes act as a catalyst, so that the food is more fully utilized and the body gets better benefit from the vitamins and mineral content, and for this reason eating sprigs of watercress with our meals, is most beneficial. But note, to get the benefit of the enzyme action the leaves need to be eaten fresh, as the heat of cooking destroys enzymes.
Watercress contains more sulphur than any other vegetable, except horseradish. Sulphur rich foods play an important part in protein absorption, blood purifying, cell building and in healthy hair and skin.
The potassium content of watercress is valued for weight loss, as its diuretic action draws excess fluid down and out of the body. Dieters will benefit with eating high potassium foods and eliminating or cutting back on high sodium foods, including salt. The rich calcium content of watercress has been encouraged for soft teeth and weak bone conditions. Chew watercress for bleeding gums. A cough medicine, utilized finely chopped leaves steeped in honey overnight. Watercress juice was mixed with vinegar and consumed for lethargy and drowsiness. A folk-remedy for allergies, watering eyes, sneezing and stuffy head, said these conditions could be cleared by regularly eating several handfuls of watercress. The saying ‘to eat cress’, was sometimes directed at people whose wits were believed to have deserted them! To relieve headaches, make an infusion with a handful of chopped watercress leaves and 2 cups of boiling water. Cool. Strain. Soak a Chux, soft cloth or washer in the infusion and rest with it placed over the forehead. In the Middle Ages, the Salernitan School of medicine recommended rubbing the juice of watercress into the scalp to strengthen and thicken the hair. A tonic for promoting hair growth, utilized 100g watercress (finely chopped) and placed in a glass jar, covered with 100ml of alcohol (vodka or brandy) and 1 teasp. of geranium oil. This mixture was shaken several times daily for 2 weeks; then strained and bottled. A little of the tonic was rubbed into the scalp daily.
Use watercress as a poultice for swollen feet and sprained ankles. Watercress is valued for clearing and improving the complexion, by eating and applying externally as a lotion. Fresh juice was applied to the face and skin to fade freckles, spots and blotches, and to clear acne, blemishes, pimples, and blackheads. The juice was applied at night, and washed off in the morning. For a beauty skin lotion, mix 1 tablesp. of honey with 4 tablesp. of watercress juice. Bottle and keep in refrigerator. With cotton wool, dab the lotion on the skin morning and evening, taking care to avoid the eyes. Betty Kamen Ph.D. in her book, ‘Germanium, a new approach to immunity’ shares research on the benefits of plants that contain the mineral germanium. Watercress is a source of the germanium. Germanium acts as an antiviral, antibiotic, and body detoxifier; an oxygen carrier and catalyst; strengthening bone-mass, the immune system and biologically stimulating electrical impulses at cell level. Germanium also plays a role as an adaptogen, helping the body to help itself work to alleviate minor or major health imbalances or to keep the body free of problems, acting both as therapeutic and preventative.
Several herbal writers say that watercress should be eaten in moderation, warning that too much over too long a period of time may cause cystitis or other bladder problems due to its strong diuretic properties. While another writer, indicates eating 2 handfuls a day is most beneficial, and another writer says to use watercress unstintingly and be lavish with it in salads. I like to eat watercress regularly. Terri Teague and Mildred Jackson in ‘The Handbook of Alternatives to Chemical Medication’ list watercress as, ‘A wondrous source of nutrients for the body and to help clear cancerous growths’. The Sunday Mail April 1997 reported how watercress can block cancer; ‘Scientists have found that the salad vegetable watercress contains a chemical, which helps prevent lung cancer’. Researchers said that a daily intake of watercress turned one of the four major cancer-causing agents in tobacco smoke, into human waste. It is the first time a vegetable has been found to have a beneficial effect on a lung carcinogen in humans. Scientists were working, to condense the key anticancer ingredient in watercress, into a pill. Monash Medical Centre’s leading research nutritionist, reported watercress was one of a number of foods, including green tea and soy products, which could interrupt one of the key pathways of developing lung, breast and bowel cancer. When I contacted the University recently and one of the researchers, I found that nothing further appears to have been done. Why is it that we do not hear more about such research discoveries? Is it, that vested interests do not want us to know the facts? Read the book, ‘World without cancer, the story of vitamin B17’ by Edward Griffin, which reveals, how science has been subverted to protect entrenched commercial and political interests. The book explores the revolutionary concept that cancer is a deficiency disease, the substance missing being B17 (also called laetrile), discovered by German chemist Leibig in1830, and further researched by Dr. Ernst Krebs and others. Their research found vitamin B17 stimulated the hemoglobin (red blood cells), strengthened the immune system, acted as a pain reliever for terminal cancer sufferers and other diseases by releasing benzoic acid, which has a natural analgesic effect. It was found that organic cyanide and benzaldehyde released from the laetrile molecule by an enzyme action, could destroy cancer cells, and leave healthy cells undamaged. Dr. F. Krebs made the point that laetrile was not cyanide poisoning, by injecting himself with a syringe filled with pure laetrile, without suffering any ill effects. A therapeutic dose is listed at 250-1000mg daily, with a toxic dose level of 3,000mg.
Then why was B17 banned by the Government? In 1974 when Griffin’s book was published, he said that the drug aspirin creates toxicity in the body and is accumulative. Researchers say laetrile is less toxic than sugar, and that aspirin is 20 times more toxic than the equivalent amount of laetrile. In the United States over 90 people die from aspirin poisoning annually. The B17 molecule contains 2 units of glucose (sugar) one of benzaldehyde, and one of cyanide all tightly locked together within it, and in its natural state it is completely inert chemically. Its action in the body, is completely utilized in a few hours, leaving behind absolutely no build-up. Aspirin is a drug, alien to nature and the body, whereas B17 is a vitamin found in some plants that are used for human consumption. This is where watercress comes in, as it has approximately 98mg of vitamin B17 per 100 grams of leaves. Watercress has been included by some people, in the Essiac mixture of herbs (see p 52).
Also, noteworthy is the fact that watercress is a food with alkalinity of 8.1 in metabolic reaction, making it valuable in our daily diet; to counteract an acidic system, caused by overall consumption of too many acid foods, processed foods, stresses and pollutants in the environment. Watercress is a powerful cleanser of the body, especially the bloodstream. It has properties that help dissolve fatigue-causing fibrin, coagulated in the blood vessels.
Culinary Uses
Watercress stimulates digestive juices. The tangy taste and smell of the leaves are indicated in the plant’s generic name Nasturtium which comes from Latin ‘nasi tortium’ meaning nose twitching; no doubt due to the peppery taste, which causes a contraction of nasal and mouth muscles. The term ‘officinale’ refers to the herb, being noted in the ‘official list’ of the most important medicinal herbs, a place most deserving for watercress, as there are few herbs that are richer in the large array of vitamins and minerals, which are essential to the human body. Watercress being a Brassicaceae plant and in the same family as mustard, has the typical pungent flavour due to the chemical compounds known as isosalfocyanic glucosides. When getting to know and appreciate watercress, if this pungent flavour is too strong, chop up the leaves finely, sprinkle over other salad leaves or vegetables, and the peppery flavour will hardly be noticed.
The very best way to get the full nutritional value of watercress is to pick just before a meal and eat. Add to cooked dishes, salads, soup, stews, and stir-fries, just before serving. The English tradition of watercress sandwiches was a favourite at garden parties. Watercress, tomato and cheese are a tasty combination in salads. Try serving sprigs of watercress as a garnish on platters of vegetables, and the leaves also make a good accompaniment with diced paw paw and pineapple. Watercress can be the main ingredient in pesto or in soup. Use the leaves in omelettes, pies, quiche, casseroles, dips, rice dishes and stuffings. Try the following combination, which a friend shared with me: chop some watercress in 1- 2cm lengths, toss through a little lemon juice and a pinch of sugar and serve on bread. A little stevia or Aztec sweet herb could be used instead of sugar.
http://www.herbsarespecial.com.au/free- ... cress.htmlTìm hiểu thêm :
Watercress
1. Q: What is the difference between watercress, creasy, and dryland cress? Do you have any idea how to prepare watercress for consumption?
A: Water-cress is a hardy, perennial, European herb (Nasturtium officinale) which grows naturally in wet soil along and in spring brooks, dithces and pond margins and is cultivated under such condition for use as a garnish and a piquant salad. It must be harvested before flower buds appear or the leaves become too rank in flavor to be edible. There are many types of cress such as Garden Cress or Pepper-grass (Lepidium sativum), Upland or Winter cress (Barbarea vernapraecox) , Bitter-cress (Cardamine pratensis), Indian-cress (another name for nasturtium) or Tropaeolum majus, Penny cress or species of Thlaspi, rock-cress or species of Arabis, Stone-cress or genus Aethionema and Wart-cress or species of Coronopus. I wonder if one of these might be also known as creasy, and dry land cress?
Store this stuff in the refrigerator with its stems in water and the leaves loosely covered with a plastic bag. Most Westerners eat watercress raw. In the East it is blanched, the moisture wrung out and then chopped and tossed with a light sesame oil dressing. Chinese often stir fry it with a little salt, sugar, and wine or use it in soups.
http://plantanswers.tamu.edu/vegetables/watercress.htmlNếu quý vị không thể ăn sống thì có thể nếu canh, quỳ vị có thể giảm vị đắng bành cánh nấu thêm với bắp cải, củ cải, cải ngọt... khi nước sôi bỏ rau xà lách xong vào và tắt bếp.
