A small study has shown that people tend to believe that bottled water is somehow healthier than water from the tap. However, the research, published in the open access journal BMC Public Health, also shows that people are unsure exactly what these benefits might be and that they are rarely the main reason for choosing bottled.

Lorna Ward led a team of researchers from the University of Birmingham who carried out interviews with users of the University's sports centre. She said: "The majority of participants believed that bottled water has some health benefits, but that they were not necessarily significant or superior to the benefits provided by tap water. Convenience and taste were more influential factors for participants when deciding to buy a bottle of water".

Bottled water was described as being more 'pure' than tap water, and was also described as containing more 'minerals'. As one respondent put it,

"I mean I know it's good but I'm not sure why it's good"

However, most participants expressed doubts as to the extent of the health benefits of bottled water compared with tap water, believing that bottled water did have health benefits, but that these benefits were negligible. The most commonly cited reason for purchasing bottled water was convenience. The researchers conclude that, "Our results suggest that the recent surge in bottled water consumption may not be motivated by beliefs about health benefits associated with bottled water".