I have no medical background but from all that I have read on this subject and other simillar stories, it would appear that by reducing her salt intake and increasing water, she has reduced her essential mineral salt levels, either because there is more to the story or because she had a tendancy toward such a situation.
I also know of cases where people who have abused controlled drugs like Ecstasy in the 'Club Culture' and drank lots of water but sadly died are often found to have dluted their mineral salts so much that they suffer from heart attacks.
Anybody who is sole source gets their Minerals and Nutrients from the Food Packs etc.
The reasons to hydrate have often been discussed... whether a person is SS dieting or not and having tried very hard in the past, I have found it very difficult to get amywhere near what is deemed a dangerous amount of water.
I would suggest that people remember the risks, manage their health and if needs be, take responsibility and take themselves to their GP or dietician... especially if they start to feel unwell.
I understand why our friends and family don't always understand what these diets are all about - especially if they don't have eating or weight issues. It seems to me that the story in the press has lots of the same language but is actually a very different scenario.
Please take care, relax, stay strong and face your concerns head on and certainly don't resort to food to try and alleviate your worries. Good health and good luck.