Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Protective effect of calcium in reducing colon cancer polyps lasts for years

19.04.2005


Long term use of calcium supplements provides a protective effect that lasts for years against development of potentially precancerous colon polyps, researchers at Dartmouth Medical School say.



Their study, presented at the 96th Annual Meeting of the American Association for Cancer Research, found that patients in the treatment group of a randomized trial of calcium supplements had a 36 percent reduction in polyp formation in the five years after the end of the trial, compared to patients in the placebo group.

Although the researchers believe it is premature to recommend widespread use of calcium supplements for chemoprevention, they say their research is the second major study that shows the value of calcium in protecting people at risk of developing worrisome polyps.


"This provides further evidence of the potential of calcium to be used as a chemopreventive agent against development of colorectal cancer," says the study’s lead author, Maria Grau, M.D., a research associate in the Section of Biostatistics and Epidemiology at Dartmouth. Co-author John Baron, M.D., a professor of medicine, will be presenting the results at AACR.

Calcium is the most abundant mineral in the body and is essential for the formation and repair of bone and teeth. It is known to play a role in such activities as nerve transmission, muscle contraction, and blood clotting.

It is also the only dietary substance that has been shown to be chemoprotective against development of colorectal polyps. The trial that proved that association, the Calcium Polyp Prevention Study, randomized 930 patients who had a history of developing precancerous adenoma to either 1200 mg. of elemental calcium supplements daily for four years, or to a placebo medication. Results demonstrated a statistically significant 19 percent overall reduction in polyp formation among participants who used the calcium supplements. The reduction in risk of advanced adenomas – more worrisome polyps with a closer association with cancer, was even larger at 28 percent.

The findings being reported at AACR is a continuation of that study. The Calcium Follow Up Study was designed as an observational phase to track polyp formation in those who participated in the Calcium Polyp Prevention Study, as well as to look at the effect of additional use of calcium supplements among the participants.

The Dartmouth research team obtained information on 822 of the original subjects, including detailed records from follow up colonoscopies performed on 597 participants.

Even while adjusting for the use of calcium supplements after the primary study was over, the researchers learned that patients who had been randomized to daily use of the mineral during the trial had a significant reduction (36 percent) in the development of new adenoma polyps during the first five years post-study. There was even a larger effect for protection against development of non-neoplastic hyperplastic polyps - a 48 percent reduction of risk.

But they also found that the protective effect diminished over time. Over the entire follow-up period, which was as much as 10 years in some patients, the protective effect fell to a non-significant 19 percent in patients who had used the supplements in the study. Patients who used calcium supplements after the randomized trial had ended had a non-significant 15 percent reduced risk of developing polyps.

Calcium’s long-term protective effect may be due to suppression of a precarcinogenic process that itself takes years to develop, Baron says, but adds that more study is needed to confirm that notion.

Warren R. Froelich | EurekAlert!
Further information:
http://www.aacr.org

More articles from Health and Medicine:

nachricht Routing gene therapy directly into the brain
07.12.2017 | Boston Children's Hospital

nachricht New Hope for Cancer Therapies: Targeted Monitoring may help Improve Tumor Treatment
01.12.2017 | Berliner Institut für Gesundheitsforschung / Berlin Institute of Health (BIH)

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

Im Focus: A transistor of graphene nanoribbons

Transistors based on carbon nanostructures: what sounds like a futuristic dream could be reality in just a few years' time. An international research team working with Empa has now succeeded in producing nanotransistors from graphene ribbons that are only a few atoms wide, as reported in the current issue of the trade journal "Nature Communications."

Graphene ribbons that are only a few atoms wide, so-called graphene nanoribbons, have special electrical properties that make them promising candidates for the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

Blockchain is becoming more important in the energy market

05.12.2017 | Event News

 
Latest News

Making fuel out of thick air

08.12.2017 | Life Sciences

Rules for superconductivity mirrored in 'excitonic insulator'

08.12.2017 | Information Technology

Smartphone case offers blood glucose monitoring on the go

08.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>