In bottle feeding, why can you only boil the water once?

[Wills]

I'm just curious and if anyone out there knows? When can you stop boiling the water just once? dd3 has one bottle a day (just before bed) and she's 5 months and grabbing anything and everything and shoving into her mouth. With three other children around she's not having the same 'protected' environment that the first one had so I wondered whether the rule of boiling once only still applied?

I think it's something about the minerals in the water -- boiling alters the balance of minerals in some way and if you do it more than once it's not great (not sure of details). So, not about germs or whatever.

Sorry, don't know how long the rule applies for -- although I'd guess it's just a blanket rule for however long you are using formula.

Do you mean freshly boil each time to make a bottle? I read somewhere that repeated boiling can lead to a build up of sodium but don't know when/if it becomes safe for a baby/toddler.

Oh, if that's the reason then it would definitely apply thoughout water boiling. I understand that know. Thanks guys. Will continue to hover around the freshly boiled kettle protecting it with a glare at anyone who would care to want a cuppa!