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.
Keeping Foods Warm While Other Foods Get Done. If you're preparing several foods that get done at different times, you often can successfully hold most hot foods for about 15 to 20 minutes in a preheated oven set to 200 to 250 degrees F.