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100% cotton, wool and linen are the only breathable fabrics that are natural. Any synthetic material is hot and attracts heat and makes you sweat. A nice shirt that is not tucked in (If they allow you to leave your shirts out). Some schools make you tuck-in all shirts. Leather belts are less hot than the synthetic belts or plastic belts. The only other material that is not too bad for heat purposes is rayon but it depends on the quality of the fabric. It could be hot as well. Polyester is very hot and should not be worn that much as it is not good for the skin to breathe. Silk is a very natural fabric as long as it is 100% but it will make you hot unfortunately. Silk is an nice winter fabric.
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