Hi Mandy - welcome to Ribena-World. I too turn a beautiful beetroot shade. Alas it happens regardless of how fit I get or when I'm taking it easier. It's genetic and nothing to worry about.
It's taken me a while and I still feel self-conscious sometimes around strangers and non runners at the end of races but now I just joke about it and my club mates have all said along the lines of "who cares what we look like - we're running and that's what matters".
Besides - take a look in the mirror a couple of hours later - all that lovely blood rushing to your face will leave you with a lovely, healthy complexion afterwards.
Derek - i'm no doctor but going pale is usually sign that the blood has all rushed to your internal organs to protect them in the absence of enough oxygen. If you don't feel like your working anaerobically and can keep going - you maybe have some sort of circulatory issue and as exercise increases the number of capillaries it may improve over time. If you're concerned, maybe have a chat with your GP. It may just be the way you are - just the same as us being the Ribena gang.
