Friday, February 16, 2007

Watercress 'helps protect against cancer'


Eating watercress regularly could help protect against cancer, a study published today has claimed.

The salad leaf contains ingredients that help prevent damage to the body’s cells and DNA, the researchers suggest.

In the study, led by the University of Ulster, 30 men and 30 women, half of whom were smokers, ate 85g of watercress a day - the equivalent of a small bag of pre-prepared salad - for eight weeks, in addition to their regular diet. The results of blood tests on the participants showed a 22.9 per cent reduction in DNA damage to white blood cells. Damage to DNA is considered by scientists to be an important trigger in the development of cancer.

The study, published in the American Journal of Clinical Nutrition, also noted a 100 per cent increase in levels of the molecule lutein and a 33 per cent rise in beta-carotene, both of which possess antioxidant properties, which help cells defend themselves against damage.

Other foods said to be rich in lutein include peas, spinach, parsley, kale and broccoli, while good sources of beta-carotene are spinach, carrots and red peppers, as well as yellow fruit such as mango, melon and apricots.

The research, which was funded by British watercress suppliers, suggested that increased concentrations of carotenoids - naturally occurring food pigments that contain vitamins -could improve the antioxidant effects.

“The results support the theory that consumption of watercress can be linked to a reduced risk of cancer via decreased damage to DNA and possible modulation of antioxidant status by increasing carotenoid concentrations,” the report concluded.

The benefits of eating watercress were especially notable among smokers, possibly because they had significantly lower antioxidant levels at the start of the research compared with non-smokers, owing to their habit, the study added.

Professor Ian Rowland, who led the project, said he believed the findings were “highly significant”. He said previous studies showed links between higher intakes of cruciferous vegetables – such as broccoli - and a reduced risk of several cancers.

“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,” he said. “Most studies to date have relied on tests conducted in test tubes or in animals, with chemicals derived from cruciferous vegetables.

“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.”

Cancer Research UK said the study was not large enough to show a clear link to a decreased risk of cancer. Dr Anthea Martin, a science information officer at the charity, said: “While the results of this study are interesting, it involved a relatively small number of people. Larger studies are needed to determine whether the effects of watercress on cells seen by the researchers translate into a decreased risk of developing cancer.

“We do know that a healthy, balanced diet, including plenty of vegetables and fruit and limited amounts of red and processed meat, can help reduce the risk of cancer.”

The charity is funding a study of 500,000 people across ten countries looking at the effect of foods on cancer risk.

The watercress study was funded by the Watercress Alliance, which is made up of three producers, Vitacress Salads, Alresford Salads and The Watercress Company.

Also see: Eating raw watercress every day may reduce risk of cancer

Source: Times Online

Wednesday, February 14, 2007

Calcium and vitamin D enhance heart health benefits of weight loss

Weight loss and reduced waist circumference are related to an improvement in heart health and factors related to metabolic syndrome. According to a new study, supplementing with calcium and vitamin D during weight loss enhances heart health benefits in women with typically low calcium intake.

Recent research has shown that overweight individuals with low calcium and dairy consumption are at increased risk of developing metabolic syndrome. The findings suggest that adequate calcium intake could create a healthier metabolic profile similar to a balanced diet and regular exercise. In a new study, researchers investigated this issue by testing cardiovascular benefits of long-term calcium supplementation in women with usual low calcium intake. Healthy, overweight or obese women with a daily calcium intake of less than 800 mg/day were randomly assigned to 1 of 2 groups: the group consuming 2 tablets/day of a calcium + vitamin D supplement (600 mg elemental calcium and 200 IU vitamin D/tablet) or the group consuming placebo. Both groups completed a 15-week reduced calorie weight-loss program. Significant decreases in LDL cholesterol levels, as well as the ratios of Total to LDL and LDL to HDL were seen the calcium +D group. These changes were independent of the changes due to fat loss and reduced waist circumference. A tendency for more beneficial changes in HDL cholesterol, triglycerides, and total cholesterol was also observed in the calcium +D group.This was the first study to show that consumption of calcium +D during weight- loss enhances the beneficial effect of body weight loss on cardiovascular risk factors in overweight women with typically low calcium intake.

Source: Supplementation with calcium + vitamin D enhances the beneficial effect of weight loss on plasma lipid and lipoprotein concentrations, Geneviève C Major, Francine Alarie, Jean Doré, Sakouna Phouttama and Angelo Tremblay, American Journal of Clinical Nutrition, Vol. 85, No. 1, 54-59, January 2007

Tuesday, February 13, 2007


Image source: author unknown

General Description

Cancer can be defined as uncontrolled cell division. When cells in some areas of the body duplicate without control, the excess tissue that develops is called a tumor or neoplasm.
Tumors may be malignant and may spread (metastasize) to other parts of the body, or benign. Benign tumors are generally not harmful because they do not spread to other parts of the body. However, benign tumors may sometimes be removed to prevent disfigurement or interference with normal body function. (1)


Several factors may contribute to the loss of control of cell division. Agents which can can contribute to uncontrolled cell division are called carcinogens.

Chemical and other environmental factors (including lifestyle choices such as diet and smoking) are associated with an estimated 60 - 90% of all human cancers. Viruses may also initiate the cancer process. Ultimately, these mechanisms either directly or indirectly influence the cellular genetic program which control cell division.(1)

Much cancer research today is directed at understanding the genetic and biochemical mechanisms which cause the suppression of the normal cellular division process. Normally, if a cell becomes damaged by a carcinogen, there are mechanisms to eliminate these defective cells. However, when a cell becomes cancerous, many of these inherent mechanisms are also affected.(2)

At Risk

Both "lifestyle" and environmental factors play a major role in the risk for developing cancer. Lifestyle factors include diet, smoking, alcohol consumption and exposure to the sun. Environmental factors include air and water pollution.

The hydrocarbons in cigarette smoke are carcinogenic and it is not surprise that 90% of all lung cancer patients are or were heavy smokers.

Additionally, certain genetic predispositions may exist for certain cancers, but it is unclear how much is due to genetic susceptibitly and how much is due to similar lifestyles in related individuals. (1,2)

Prevention and Management

The best way to reduce the risk of cancer is to reduce or eliminate exposure to potential carcinogens. It is estimated that 80% of all cancers can be prevented by lifestyle changes such as diet, quitting smoking and reducing exposure to the sun.(1)

Diet may be a major factor in 30 to 40 percent of all cancers in men and for 60 percent of all cancers in women. Colon and breast cancer have a strong link to diet.(3,4)

Some of the foods we eat can contain cancer promoters. These include fat, alcohol and salt-cured and smoked foods.(2)

Many foods also contain compounds which help protect against cancer. There is a well established correlation between fruit and vegetable consumption and cancer risk. In particular, fruits and vegetables are sources of fiber, beta carotene, vitamin C, and other compounds associated with lower risk for cancer. However, individuals rarely consume enough of these to ward off potential carcinogens.(2,5)

Many plant-derived compounds (referred to as phytochemicals) show promise in both prevention and inhibition of the cancer process. Many of these phytochemicals operate as antioxidants and reduce the damage caused by free radicals. It is theorized that free radical damage to a cells genetic machinery may be one of the mechanisms of cancer promotion.(3,6,7)

These phytochemicals include allyl sulfides (onions, garlic, leeks, chives), indoles and isothiocyanates (cruciferous vegetables), isoflavones (soybeans), phenolic acids (tomatoes, citrus fruits, carrots), polyphenols (green tea, grapes, wine), saponins (beans and legumes) and terpenes (cherries, citrus fruit peels).

Eating a variety of vegetables and fruits is more important than concentrating on particular kinds to get the full gamut of phytochemicals found in nature. The following guidelines are recommended by the American Institute of Cancer Research (AICR):
1) eat more grains,
2) eat a variety of vegetables,
3) eat more fruit,
4) season with herbs and spices instead of salt,
5) decrease portions sizes of meat fish and poultry,
6) explore new foods and new recipes.

Additional Information
Disclaimer: These websites, addresses and/or phone numbers are provided for information purposes only. USANA, Inc. makes no claim, actual or implied, regarding the content or validity of the information obtained from these outside sources.

American Institute of Cancer Research. 1759 R Street N.W., Washington, DC 20069, 1-800-843-8114

Ames BN, Gold LS, Willett WC. The causes and prevention of cancer. Proc Natl Acad Sci U S A 1995 Jun 6;92(12):5258-65. Epidemiological evidence indicates that avoidance of smoking, increased consumption of fruits and vegetables, and control of infections will have a major effect on reducing rates of cancer. Other factors include avoidance of intense sun exposure, increases in physical activity, and reduction of alcohol consumption and possibly red meat. A substantial reduction in breast cancer is likely to require modification of sex hormone levels, and development of practical methods for doing so is a high research priority. Resolution of the potential protective roles of specific antioxidants and other constituents of fruits and vegetables deserves major attention. Mechanistic studies of carcinogenesis indicate an important role of endogenous oxidative damage to DNA that is balanced by elaborate defense and repair processes. Also key is the rate of cell division, which is influenced by hormones, growth, cytotoxicity, and inflammation, as this determines the probability of converting DNA lesions to mutations. These mechanisms may underlie many epidemiologic observations.

1 Ruddon, RW. Cancer Biology. Oxford University Press. 1995.
2 World Cancer Research Fund/American Institute for Cancer Research. Food, Nutrition and the Prevention of Cancer: a global perspective. Banta Book Group, Menasha, WI. 1997.
3 Bidlack WR, Interrelationships of food, nutrition, diet and health: the National Association of State Universities and Land Grant Colleges White Paper. J Am Coll Nutr 1996 Oct;15(5):422-33
4 Bland JS. Phytonutrition, phytotherapy, and phytopharmacology. Altern Ther Health Med 1996 Nov;2(6):73-6
5 Fraser D. Nutrition and cancer: epidemiological aspects. Public Health Rev 1996;24(2):113-21
6 Halliwell B. Oxidative stress, nutrition and health. Experimental strategies for optimization of nutritional antioxidant intake in humans. Free Radic Res 1996 Jul;25(1):57-74
7 Cassileth BR and Chapman CC. Alternative cancer medicine: a ten-year update. Cancer Invest 1996;14(4):396-404


Monday, February 05, 2007

Lifestyle improvements are as effective as medications in reducing diabetes risk

Lifestyle changes appear to be at least as effective as medications in delaying or preventing type 2 diabetes among adults with impaired glucose tolerance, and are associated with significantly fewer side effects according to a new report published in the British Medical Journal.

The increase in obesity and decrease in physical activity in Westernized societies are strongly linked with the increase in prevalence and incidence of type 2 diabetes. People with impaired glucose tolerance have an increased risk of developing type 2 diabetes, and many trials have focused on such individuals. Various treatment methods have been utilized in research, including pharmacological (medications), lifestyle and herbal remedies. A recent meta-analysis published in the British Medical Journal consolidated the evidence from 17 clinical trials that studied the effects of lifestyle, drugs and other methods on men and women with impaired glucose tolerance. Results showed that intervention can reduce the risk of type 2 diabetes in high risk individuals, and lifestyle changes seem to be at least as effective as drug therapy. Compared to individuals who received standard advice only, the effect of lifestyle changes resulted in a 49 percent reduction in the risk of developing diabetes. Exercise alone or exercise combined with a healthier diet was more effective than diet alone. Oral diabetic medications were also effective in delaying or preventing diabetes, but were not as effective as lifestyle changes. Orlistat, an anti-obesity drug, was also effective in reducing risk when compared to control groups. Although both medications and lifestyle changes were effective in reducing the risk of diabetes, diet and exercise were associated with considerably fewer adverse effects than those caused by pharmaceuticals, which were typically gastrointestinal effects and reduced liver function. Since it is fundamentally a lifestyle issue, the authors had concerns about the practice of treatment with a lifelong course of medication, especially since even minor adverse effects become more significant if a medication is to be taken for life. But they also noted that compliance is generally the key when it comes to lifestyle interventions, so strategies to improve compliance need to be enhanced and put into action.

Source: Pharmacological and lifestyle interventions to prevent or delay type 2 diabetes in people with impaired glucose tolerance: systematic review and meta-analysis, Clare L Gillies, Keith R Abrams, Paul C Lambert, Nicola J Cooper, Alex J Sutton, Ron T Hsu, Kamlesh Khunti, BMJ 2007 Jan 19