The primary difference between the Gildan 5000 and Gildan 8000 lies in their fabric composition and the benefits each offers. The Gildan 5000 is made from 100% cotton, providing a classic, soft, and breathable feel, making it ideal for everyday wear. On the other hand, the Gildan 8000 is a blend of cotton and polyester, which introduces moisture-wicking capabilities, making it suitable for active use and warmer climates.