News

Cancer patients should be extremely cautious about popping supplements - the pills may interfere with their medical treatment.

A new study, published this week in the journal Cancer Research, suggests that vitamin C tablets significantly reduce the effectiveness of a wide range of cancer-fighting drugs.

Daily supplements containing just 100 milligrams of vitamin C "could have the potential to reduce the ability of patients to respond to therapy," the lead researcher, Mark Heaney of Memorial Sloan-Kettering Cancer Center in New York, warned in a statement released with the study.

The researchers pretreated cancerous cells with vitamin C and then exposed them to a selection of different chemotherapy medications in the lab. The drugs killed between 30 and 70 per cent fewer of the tumour cells infused with vitamin C than would normally be expected to die.

Tests involving mice produced similar results. Tumours grew more rapidly in mice given vitamin C before receiving chemotherapy, compared with tumours in supplement-free mice. Although more research is needed to confirm the findings, Dr. Heaney believes comparable reactions would take place in human patients.

But why would vitamin C undermine cancer therapy?

The research, Dr. Heaney said, also revealed that vitamin C appears to protect mitochondria - tiny power plants that generate energy within a cell.

"Mitochondria are very important regulators of cell health. And when they aren't healthy, they cause the rest of the cell to die," he explained in an interview.

One way chemotherapy works is by attacking mitochondria within cancerous cells to trigger their death.

However, when vitamin C shields the mitochondria from damage, the full effectiveness of the chemotherapy is essentially "blunted," he speculated.

Even so, "everyone needs some vitamin C ... If you don't have vitamin C, you get scurvy," he stressed.

"Patients [should] continue to eat a well-balanced diet that includes fruits and vegetables, but not to take extra vitamin C in the form of supplements."

SPOOKED FOR GOOD

Just the suggestion that someone may be watching is enough to keep some people honest - even if those "watching eyes" happen to be in the spirit world.

In a study involving university students, some of them were told that the ghost of a dead student had been spotted in the experiment room. When the students were later asked to perform a computer task, those informed about the ghost cheated less than those who were unaware of the possible presence of a spirit, according to an article published today in Science.

The authors, Ara Norenzayan and Azim Shariff of the University of British Columbia, explore the role that religion plays in enticing people to act in a "pro-social" manner - behaviour that benefits others.