These are not perfect solutions but you could try adding:
-webkit-font-smoothing: antialiased;
and see if that helps. It might give you a slightly thinner font though ...
Sometimes, adding:
-webkit-backface-visibility: hidden;
to the affected elements helps, but I'm not really sure why, and as a third fix you can try to add:
-webkit-transform:translate3d(0,0,0);
which will force hardware acceleration and in this case make the font, as the fix above, unified but slightly thinner ...
But, since you haven't provided any code to your question, my answer is more of a guess.
Anyway, I hope it helps!