Some of Karen Smith's earliest memories are of waiting for her mum while she gave blood.
'I still remember sitting in the tea area with my juice and biscuit, picking out the sticker I was going to take home to show my dad.'
'Then my mum stopped giving blood for a while, so I stopped going with her, and for years I never thought about the need for blood. Then one day when I was on my way home from college, and my bus passed the Town Hall in Kirriemuir and the Give Blood lorry was parked outside. I had a few hours to spare, and I remembered the times I'd been there with my mum, so I thought why not? I walked in, registered there and then and gave blood for the first time. Since then I've given 37 donations.'
'I'd encourage you if you have never given before. Don't be scared, it's not that bad - I don't like needles either, but you just don't look and you don't feel anything. The staff are so professional and welcoming, it's such a relaxed atmosphere, everyone is so friendly. That's why I come back time after time.'
Karen explains why being a blood donor is so important to her.
'I want to help people. I think that we just expect the blood to be there, and we really don't think about how it happens. We don't think about how a hospital runs, that blood is needed every day to allow surgery to take place, for babies to be born. I suppose most people just think you turn up and give, and then your donation goes to the patient. They don't think there has to be a regular supply. Blood doesn't come out of a tap.'
'The Scottish National Blood Transfusion Service (SNBTS) aim to stock six days supply of each blood type. I follow their social media page and I saw my type was needed this week, so I changed my appointment to come a little earlier (it had been more than 12 weeks since my last donation).
'I know my type and that my donations was needed so I was able to answer their call.'
If you'd like to become a lifesaver like Karen, you can register as a blood donor by calling 0345 90 90 999. You can also sign up online.