Diabetes. If you are suffering from excessive thirst, tiredness and blurred vision, you could be among the estimated one million people in Britain with undiagnosed diabetes - a complicated condition which increases the risk of ill health and premature death from heart disease, stroke and kidneyfailure. If diabetes is affecting your life and you have a question you would like answered, contact Barbara Myers - who will be talking to experts on the condition. Producer AliAyres. E-MAIL: checkup@bbc.co.uk WEB SITE: www.bbc.co.uk/health/