Wireless body area networks (WBANs) have become a new paradigm for electronic healthcare applications; for instance, they are used to efficiently monitor patients in real-time. In this paper, an energy-efficient link scheduling (ELS) protocol for cognitive radio body area networks (CRBANs) is proposed, which aims to minimize energy consumption in CRBANs, while achieving higher probabilities of successful transmissions with multiple CRBANs. The proposed ELS transmits packets in the common control channel to control transmission links amongst CRBANs to the gateway and vice versa. The transmissions of CRBANs to the gateway are scheduled at a specific time by the gateway in different data channels, according to the traffic priority of CRBANs. Packet delivery ratio, delay, and energy consumption are evaluated for multiple CRBANs via extensive simulation.