Metasurfaces are specially made materials designed to have unique properties not found in nature. They are categorized into different types, such as Artificial Magnetic Conductor (AMC), Partial Reflecting Surfaces (PRS), and Frequency Selective Surfaces (FSS). Among these, FSS is commonly used in today's technology to improve antenna performance, especially in boosting signal strength by blocking unwanted radiation. Recent research is focused on creating FSS-based antennas for Ultra-Wideband (UWB) or single-band applications, with a significant emphasis on enhancing signal strength. Unlike traditional methods, this study concentrates on designing antennas that are both simple in shape and broad in their frequency coverage, specifically for 2.45 GHz and 5.8 GHz applications. To enhance antenna performance, a dual-band FSS is employed, optimizing the system for improved operation at both resonating frequencies. This results in a high-gain antenna system, which is further investigated for Body Area Network (BAN) systems, considering the crucial performance metric of Specific Absorption Rate (SAR). The findings are compared with recently reported FSS-based antennas to underscore their scientific contribution and potential for high-gain, low-SAR applications within the 2.45 GHz and 5.8 GHz frequency bands.