Como dizer "É ajudando que se é ajudado" em inglês

Sugestão:
One good turn deserves another.

Prov. If someone does you a favor, you should do a favor for that person in return.

Jill: Thanks for the ride.
Jane: It's the least I can do after you helped me wash the car last week. One good turn deserves another.

Child: I don't want to help Grandma go shopping.
Father: But she helped you with your homework yesterday.
And one good turn deserves another.
http://idioms.thefreedictionary.com/One ... es+another

Para os católicos

For it is in giving that we receive

Da oração de São Francisco de Assis: Prayer of Saint Francis of Assisi

...when you help someone you're helping yourself.

So, when you help others, you are helping yourself.


[Source: Linguee. With slight tinkering of mine.]




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Back to the crux, or to the initial question of yours.

"You´re welcome. And I am helping myself when I help you out./and it´s a win-win situation, I help you out and I help myself in the process."

And there´s the (many times self-serving, but not necessarily always):

You scratch my back and I'll scratch yours
(...you do something for me, I'll return the favour.)

Source: http://www.usingenglish.com

Another way to say "You are welcome is "Pass it on." By this you mean, "I ask that you help someone else as I have helped you."

I do not recall hearing among Americans anything close to "É ajudando que se é ajudado."