Chemotherapy: Selenium Increases the Effect and Reduces Side Effects

September 20, 2004

There are still a few cancer specialists, who warn their patients against taking antioxidants while undergoing chemotherapy. They think that when antioxidants decrease the side effects of the treatment, they will also decrease the benefits of chemotherapy. However, pursuasive studies now show that this advice is neither correct nor beneficial.

Scientists at the famous and internationally acclaimed American Roswell Park Cancer Institute – the oldest independent cancer research centre in the world – are putting forward these new results.

Highly detailed studies on mice have shown that not only does selenium protect healthy tissue from the destructive effect of chemotherapy – it also quite dramatically enhances the effect of chemo therapy on tumours! For the first time, it has been established that it is possible to increase the effect of chemotherapy with a treatment that is actually harmless in itself.

The studies were carried out on so-called naked mice that had various human tumours surgically implanted and then were given various types of chemo theray. Some of the tumours were moderately sensitive to chemotherapy while the sensitivity of others was very small. However, when the mice were treated with large doses of selenium, they were able to tolerate up to four times as much chemotherapy as they normally would and thereby, not only the usual 20 – 30% of the mice could be cured, but in some cases up to 100% of the mice were cured!

Just as convincing was the effect on moderately sensitive tumours which are usually cured in about 50% of the cases. With selenium, the success rate went up to 100% and, to a very large extent, the mice were also free from side effects.

The preliminary results indicate that there might be several reasons for these results, but selenium in combination with chemotherapy seems to be able to force the cancer cells into committing suicide, so-called apoptosis.

Attention must be paid to the fact that this is an animal experiment. However, the results have been so exceptional and promising that the researchers at Roswell Park Cancer Institute are already setting up the first studies for testing the treatment on humans.

By: Vitality Council

Reference:
Shousong Cao, Farukh A. Durrani, and Youcef M. Rustum. Selective Modulation of the Therapeutic Efficacy of Anticancer Drugs by Selenium Containing Compounds against Human Tumor Xenografts. Clin Cancer Res. 2004;10(7):2561-9.

clincancerres.aacrjournals.org
www.roswellpark.org
www.iom.dk

Selenium Reduces the Risk of Serious Prostate Cancer by 50%

July 19, 2004

More research indicates that the mineral selenium protects men against prostate cancer.

In the largest comparative study thus far, a large group of American doctors were examined and it was demonstrated that the ones who were in the top 20% with the highest content of selenium in their blood had a 48% reduced risk of getting advanced prostate cancer compared to their colleagues with less selenium in their blood.

This reduction correlates well with several other studies in recent years, but the present study published in the Journal of the National Cancer Institute in America is the largest on this subject so far. A total of 586 male doctors who during the course of 13 years were diagnosed with prostate cancer were compared to 577 male doctors who avoided the disease.

Many men get prostate cancer but this does not necessarily result in long-term consequences because the disease is often localized and non-invasive. These mild forms of cancer were apparently not prevented by selenium. Only the risk of advanced cancer was reduced. This indicates that selenium delays the development of the disease rather than prevents it from arising in the first place.

Large studies of the connection between selenium and prostate cancer are on their way. Particularly a large American study (SELECT) which is also designed to bring light to the effect of vitamin E on this disease is anxiously anticipated.

Which results would be found in a similar British study is unclear. Americans get far more selenium through their diet than British people because the American soil is richer in this mineral. Perhaps this is the reason why British men are more exposed to prostate cancer in its aggressive and malignant form.

By: Vitality Council

 

Reference:
Li H et al. A prospective study of plasma selenium levels and prostate cancer risk. J Natl Cancer Inst. 2004;96(9):696-703.

jncicancerspectrum.oupjournals.org
www.iom.dk

Important Nutrient Substance Protects Women Against Pre-eclampsia

December 17, 2003

According to a new British study, defiency of the trace mineral selenium might quadruple the risk of pre-eclampsia in pregnant women.

According to British researchers, pregnant women with a low content of the vital trace mineral selenium have up to four times as high a risk of developing pre-eclampsia compared to women who are not deficient in this substance.

This is the result of a new study published in the November issue of the American Journal of Obstetrics and Gynecology. The researchers behind the study are not quite aware why some women develop pre-eclampsia which involves hypertension, kidney damage, and reduced blood supply to the placenta.

They suggest, however, that it might be connected with the decreasing intake of selenium in several countries. In Britain, the selenium content of wheat is 10 – 50 times lower than that of the USA and Canada, for example, making it difficult to maintain an adequate intake of this important substance.

The risk of premature delivery
In the recently published study made by a group of scientists led by Dr. Margaret P. Rayman at the University of Surry in Guildford, the toe nail clippings of 53 pregnant women with early signs of pre-eclampsia were studied and compared to toe nail clippings from 53 healthy women. Selenium accumulates in nails which makes nail clippings such a good gauge of people’s selenium status.

The researchers observed that the average selenium content of the toe nail clippings were considerably lower in the women with early signs of pre-eclampsia. The researchers also found that the pre-eclamptic women with the lowest selenium values were far more likely to deliver prematurely.

One of the reasons for pre-eclampsia is believed to be oxidants (a kind of toxins) that arise as a consequence of a poorly functioning placenta. As selenium is an effective antioxidant, it is very likely that a lack of this substance can contribute to the development of pre-eclampsia.

Worries of reduced selenium intakes
The leading researcher, Margaret Rayman, has expressed her concern about the declining intake of selenium in Britain where the dietary selenium intake is reduced by more than 50% compared to what it was 20 – 25 years ago. This is due to the selenium content of crops being significantly lower than it used to be.

“Selenium is an extremely important substance which is known to be able to prevent various forms of cancer, including prostate cancer and skin cancer. What really worries me is the observation that the authorities systematically reduce the recommended daily dose of selenium while new research shows just how important it is to get adequate amounts of this substance. 15 – 20 years ago, the recommended daily dose (RDA) was 125 mcg. a day – recently the RDA was reduced to 40 mcg. This completely opposes common sense,” says Claus Hancke, the chairman of the Danish Vitality Council.

The British group of researchers are already planning a new study intended to clarify if dietary supplements of selenium can protect against pre-eclampsia.

By: Vitality Council


Reference:

American Journal of Obstetrics and Gynecology (vol. 189, no. 5).

www.ovid.com/site/catalog/Journal/369.jsp
www.iom.dk

Selenium against Breast Cancer!

June 19, 2003

A combination of nutritional research and knowledge on genetics may lead to an earlier discovery and prevention of breast cancer. New scientific research seems to indicate that dietary supplements with selenium may prevent breast cancer in those women genetically predisposed to breast cancer.

A combination of nutritional research and knowledge about genes may lead to an earlier discovery and prevention of breast cancer. New research suggests that dietary supplements with selenium can prevent breast cancer in women who are genetically exposed to the disease.

The researchers believe that there is an opportunity to find out who is in the danger zone – before the disease develops – and then preventing using selenium supplements.

By: Vitality Council

Reference:
Cancer Research, 15. June 2003.

cancerres.aacrjournals.org
www.icnet.uk

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January 1999

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