My baby is 2 months old and I've just started to take off his mittens to let him adventure with his hands, but he keep sucking his fist once the mittens are off. Even his fingers are red from the sucking. Is this okay and if not ok, how do I prevent him from this constant sucking?

I believe this is a normal behaviour as it happens to all my 4 babies. Babies are just curious about themselves and wanna explore more. Actually suckling is a form of comfort for them too. You don't have to worry at all. Do take note and make sure that the don't put their fist inside their mouth.

It's normal. Sucking is a healthy, self-comforting behaviour for newborns. A 8 week old baby will resort to sucking his own fingers – or yours – as a way of calming himself when he's upset or trying to settle down. This is self-soothing.

My son started sucking his fingers at about 2 months too and it gradually lessen over time. He's 7.5 months old now and he still does occasionally stuff his mouth with his fingers, although not so frequently anymore.

Yup, like what Rose mentioned. It is a normal behavior. You baby has simply “discovered” his hands and sucking on his fist is just a self-comforting behavior. You need not be too worried about this. :)

I removed the mittens of my baby right after his 1st month, hes not sucking his fist, but of he do so..I guess its normal because at this stage, they are now starting to explore.

even my 2 mnths old son does that...i think its normal for all babies