The soft water supply in the Westcountry could put people at a higher risk of developing alcoholic liver disease, a study has claimed.
Professor Roger Williams, who helped carry out the UK's first liver transplant in 1968 and was George Best's surgeon, helped co-author the paper.
It found those living in soft-water areas may be more at risk of developing the disease because of lower levels of magnesium which can help to protect the liver from alcohol.
The study was based on hospital admissions in 28 English regions between 2003 and 2006.
Six areas with soft water – including the South West – had rates of alcoholic liver disease 21 per cent above the national average. The 13 areas with hard water had rates 13 per cent below the average.
The figures conflict with research into published this year, based on statistics from 2001-09, which showed that the region had one of the lowest mortality rates from alcohol-related liver disease (ALD) in the country.
Prof Williams, director of the Institute of Hepatology, has suggested that magnesium could be added to the water supply in soft water areas to lessen the risk.
Medicating water supply with magnesium would prove controversial. Campaigners who have opposed adding fluoride to tap water are likely to oppose any such measure.
John Graham, spokesman for the National Pure Water Association, said: "This sounds like nonsense. Why would we want to dose all of the water and all of the population for a tiny number of people who have a problem with alcohol?
"Recommending supplements for those at risk seems much more sensible."