In my knowledge with soy it is used to replace meat or animal products such as milk but you never know what effect it could have by consuming it for a long time.

Actually the long term effects have been studied in depth and soy is safe to consume.  Unfortunately there is a lot of false propaganda that has been circulating about soy.  Human nature tends to cause many people to listen to and spread the same disinformation without ever bothering to research if the claims are true.  This has a lot to do with the fact that humans tend to be attracted to negativity.  For example, if there is a deadly wreck people want to see the carnage.  In a similar manner people tend to be attracted to spreading negative misinformation such as gossip.  In this case the target is soy but the tactic is still the same.  Expand on the lies and continue spreading the misinformation rather than finding out if the negative claims are true.