I think that once they start eating more varied foods than infant cereal you can start to slow introduce watered down versions of the simple juices, like apple....my pediatrician recommends introducing apple juice at 2 months and we tried that with Kahlan (my DD who is almost 2 yrs now) not knowing any better, and it made her leak like a sieve out of the booty if you know what i mean, LOL...so we waited until 4 months to offer 2 ounces of apple juice mixed with 2 ounces of water once a day, and she would only drink sips..and by 6 months she would drink 1-2oz of apple juice.
It really varies but I would ask your pediatrician...with my son we probably won't offer him his first watered down apple juice until 4 months, although I think that they recommend doing it so early in order to help their digestive systems learn to regulate liquids other than formula/breastmilk...but obviously all it does is make my babies leak LOL.
Anyway at 7 months he can most likely have an ounce of watered down apple juice (1-2oz apple juice mixed with 1-2oz of water) just to try...and if he tolerates that well you can start experimenting with different concentrations of it once or twice a day just to help his system get used to new liquids. You can also use it instead of water or formula to mix with his cereals and see how he tolerates that. a sip of water of a sip of juice here and there if he's thirsty between formula feedings should be fine as well...there may be other opinions on this but my daughter was drinking juice by then and she's very healthy so in my experience it's fine by that age :).
Now I don't have my baby yet, but from what I've heard just make sure you don't leave the juice with them, especially if they go for a nap because it's really not good for their teeth or gums. Also if you always give juice some children will start to refuse water so make sure it's all in moderation :)
I dunno I think it depends on the kid about the water thing...my daughter was given juice before she was ever given water, but now if you offer her a choice she ALWAYS takes water. she even prefers it over chocolate milk. it's kind of frustrating actually, lol. she's a picky eater so I offer her very healthy, mineral-packed juices hoping to supplement what she's not getting through her solids, but she'll drink a little juice and then ask for water.
But yes it's definitely true you don't want their teeth exposed for any length of time to the sugars...but it also applies for formula and breastmilk, actually.
Now it is recommended to not give juice to babies or children at all because of the sugar in them so if you ask your pediatrician that is probably what they will say. But that being said my sister started giving her kids juice around like 6 months she just used about 25% juice and 75% water (not tap). They are just fine. So you can try it to see how the baby tolerates it.
Thanks! My DH brought my son in for his 6 month appt and forgot to ask. I will try very watered down apple juice (25% aj/75% water) and see if that will satisfy him for a little while.