Vitamin C may have an important part to play in destroying cancer cells, a new US study believes.

The vitamin – which should be injected rather than swallowed for optimum results – has been shown to halve the growth of aggressive tumours in mice, killing cancer cells while leaving healthy tissue unharmed.

Usually the body keeps a tight rein on vitamin C levels in the blood.

But scientists have found that the mechanism can be by-passed if the vitamin is injected straight into the bloodstream instead of passing through the digestive system.

When this is done it releases the powerful anti-cancer potential of the vitamin, according to the researchers.

Experiments showed that high levels of vitamin C in the blood generate hydrogen peroxide, which is lethal to tumours.

The use of high dose vitamin C as a complementary or alternative cancer treatment has a long history dating back to the 1970s.

But reliable evidence that the therapy works has been lacking until now.

The new US investigation led by Dr Qi Chen, from the National Institutes of Health in Bethesda, Maryland found two hours of exposure by the mice to the vitamin significantly reduced the survival of various cancer cells.

However, an expert at the charity Cancer Research UK has issued a warning, saying there was some evidence that high doses of antioxidants such as vitamin C might hamper conventional cancer treatment.

“This is encouraging work but it’s at a very early stage because it involves cells grown in the lab and mice,” said Dr Alison Ross.

“Much more research is needed before we’ll know whether vitamin C could be a viable cancer treatment in the future.”

Via news.sky.com