Taking antacid tablets on a regular basis can increase your risk of cancer

Antacid pills taken by millions of Britons double the risk of getting stomach cancer, a major study has found. These drugs, which are used to treat ­indigestion and acid reflux, are called proton pump inhibitors, or PPIs.

And if you take the drugs for a year, the risk rises five-fold, and to more than eight-fold after three years of regular use.

The cause, according to scientists from University College London and the University of Hong Kong, is a hormone called gastrin, which triggers the growth of cancerous cells.

Though not recommended for long-term use, the drugs are readily ­available over the counter.

Fears had been rising for some time about their impact on health, with research linking them to dementia, heart attacks and kidney problems.

The new research involved 63,000 people in Hong Kong who were tracked for an average of seven years. It discovered that people who took the pills at least once a week were more than twice as likely to develop stomach cancer compared to those who didn’t use the drugs.

For daily users, the risk increased 4.5 times, and the longer people used the drugs the greater their risk, rising to an 8.3-fold greater risk for those who took the pills daily for three years.

These figures look scary, but few people get stomach cancer so the threat is small. Out of the 63,397 people studied, only 153 (0.24%) got stomach cancer.

The researchers calculate for every 10,000 people who take PPIs, roughly eight a year will develop stomach cancer – four more than if no one was taking the pills.

They said: “We found that long-term use of PPIs increased the risk of gastric cancer development. There was a clear dose response and time response trend of PPI uses and gastric cancer risk.

“Physicians should use caution when prescribing long-term PPIs.”

A spokesman for the Medicines & Healthcare products Regulatory Agency, which is responsible for drug safety in Britain, said: “PPIs available without prescription are only for short-term use and to be taken as a low dose. We keep all emerging evidence under review.”

However, Professor Stephen Evans, of the London School of Hygiene and Tropical Medicine, said the research is by no means proof of a causal effect.

The Proprietary Association of Great Britain, which represents ­manufacturers of over-the-counter medicines, said no one should take PPIs for more than two weeks without speaking to a pharmacist.

If you’re taking an over-the-counter PPI remember they’re intended for short-term use. See your doctor if your problem persists.