No. The set of primes can be whatever you want. First, note that for infinitely presented groups, the torsion can be whatever you like: the torsion in the group $*_i \mathbb{Z}/p_i$ is precisely the set of primes $p_i$, by standard facts about free products. By Higman's Embedding Theorem, the above group can be embedded in a finitely presented group. More subtlely, this embedding doesn't introduce any new torsion---see, for instance, Theorem 2.5 of [this preprint of Chiodo][1]. [1]: http://arxiv.org/abs/1107.1489