Substrates with transparency to infrared body radiation and opacity in the visible light spectrum are provided and systems and methods for creation thereof are provided. The IR radiation transparent substrate is IR radiation transparent and visible light opaque with enough breathability and softness to make it suitable for use in garments for body thermal regulation. Further, the IR radiation transparent substrate is created utilizing nanofiber technology to form specific sized micro pores between the nanofibers.

A health suit for improving sweating and tanning in various weather conditions includes a transparent material that is configured to allow ultraviolet rays and infrared energy to pass through the material and penetrate the skin with minimal deflection or absorption by the material. The health suit may also include an anti-fog layer or other set of anti-fogging features, moisture absorbing material, and a heat retention feature to improve sweating and tanning in various weather conditions.

Disclosed is a thread combining multiple polymers. The thread consists of fibers of a first synthetic polymer of the Polyethylene terephthalate (PET) family and fibers of a second synthetic polymer of the Polyimide family, wherein the first fibers and the second fibers are combined together such that the resulting material, forming the thread, blocks photons with wavelengths falling within a first range of wavelengths and allows passage of photons with wavelengths falling within a second range of wavelengths. Photons whose wavelengths are within the second range of wavelengths, allowed to pass by the resulting material, may contribute to tanning of human skin.

A swimwear apparatus is provided. The swimwear apparatus may include an upper portion having an upper base layer and an upper bikini layer, and a lower portion having a lower base layer and a lower bikini layer. The upper bikini layer may be configured to be removably attached to the upper base layer, and the lower bikini layer may be configured to be removably attached to the lower base layer.

A health suit for improving sweating and tanning in various weather conditions includes a transparent material that is configured to allow ultraviolet rays and infrared energy to pass through the material and penetrate the skin with minimal deflection or absorption by the material. The health suit may also include an anti-fog layer or other set of anti-fogging features or other set of anti-fogging features, moisture absorbing material, and a heat retention feature to improve sweating and tanning in various weather conditions.

A multilayer fabric for selectively blocking or transmitting particular wavelengths in the electromagnetic spectrum, such solar radiation, and far infrared (FIR) radiation. The multilayer fabric may include a microporous water vapor permeable layer that selectively filters particular wavelengths depending on the size of its pores. In some embodiments, the multilayer fabric may include a nanostructured layer that selectively filters particular wavelengths.