According to recent studies by the USDA, the ideal temperature for cooking a medium-rare steak on a grill is around 410°F (210°C). To ensure food safety, it's crucial that the internal temperature of the steak reaches at least 135°F (57°C) during cooking. This temperature ensures that any potential bacteria present in the meat have been destroyed, making your meal safe to eat. It's essential to use a meat thermometer to verify the internal temperature before serving as visual cues can be misleading. By following these guidelines, you can enjoy a delicious and safe steak every time.