How do I read lab results?

Every lab report has the same skeleton, and reading it is a skill you can learn in five minutes. Per line you get: the marker's name (and its abbreviation - learn yours once), your value with its units, the reference range - the span the lab considers typical - and a flag (H or L, or an asterisk) when your value falls outside it. Then the rules that keep you sane, from MedlinePlus's lab-results guidance. First, ranges are not verdicts: they are statistical spans built from healthy populations, labs use different methods and different ranges (compare your value to the range printed on YOUR report, not one from the internet), and a result barely outside the line can be perfectly normal for you. Second, one flagged value is not a diagnosis: hydration, recent meals, exercise, illness, time of day, and medications all move numbers - abnormal results usually earn a repeat or a follow-up test before they earn a name. Third, the trend is the truth: a value creeping year over year says more than any single reading, which is why keeping your old results pays. Fourth, ask the three questions that turn numbers into a plan: what does this marker measure, how far out am I, and what happens next - and get the answers in writing. Pymander is a free AI doctor, 24/7 by text, that can walk any result with you line by line.