Analysis of the data from the Office for National Statistics reveals that in 2009, the latest year for which figures are available, 816 hospital patients in England and Wales were listed on death certificates as having died suffering from dehydration.
The annual figure is up from 608 in 1997, the year Labour came to power. The highest figure over the past decade was 934 deaths recorded in 2008.
The figures include death certificates where dehydration was listed as the underlying cause, as well as those where it was a contributory factor.
Malnutrition contributed to 284 deaths in hospitals – up from 175 in 1997.
As with dehydration, some of these figures could include people who had serious illnesses such as stomach cancer – meaning not all the cases are necessarily due to neglect