The emergence of body area networks (BANs) has paved the way for real-time sensing of human biometrics in addition to remote control of smart wireless medical devices, which in turn are beginning to revolutionize the smart healthcare industry. However, due to their limited power and computational capabilities, they are vulnerable to a myriad of security attacks. To secure BAN sensors against these threats processor-intensive cryptographic techniques need to be avoided as they are not suitable in this context. This article focuses on authentication service for BAN sensors and proposes an original scheme named RAFV: Rotational Assisted Fuzzy Vaults to harden the security of any authentication solution using the fuzzy vault construction approach. The evaluation results have shown that RAFV can successfully conceal the secret of the vault even if the locking elements are known to the adversary. Also, RAFV may improve upon communication overhead by enabling a reduction in the size of the vault without compromising its security. It has achieved all of this while remaining competitive with regards to additional computational overhead.