1 Having high or low cholesterol does not exclude a person from donating blood. 2  Potential blood donors may be temporarily prevented from donating if they have a low level of iron (hematocrit) in their blood.
Headline Clickable. To keep food warm without overcooking, set your oven to the lowest temperature (which is probably 200 degrees F) and cover the food with foil.eadline Clickable. To keep food warm without overcooking, set your oven to the lowest temperature (which is probably 200 degrees F) and cover the food with foil.
Checking the Temperature. Put an oven thermometer at the center of the oven and set the oven to 350 degrees F. Check the temperature indicated on the thermometer after 20 minutes. If it's not within 5 degrees of 350, you'll need to adjust the oven's temperature control.