Understanding results
What a “normal” blood result really means
Reference ranges are not a pass or fail line. Here is how they are built, why labs disagree, and why a result just outside the range is often fine.
Most lab reports print a range next to each result, and anything outside it gets a flag. It is natural to read that flag as a problem. In practice it is a prompt to look more closely, and knowing how ranges are made explains why.
Most ranges describe the middle 95% of people
For many markers, a lab tests a large group of healthy people and sets the range to cover the middle 95% of their results. That means 1 in 20 perfectly healthy people will fall outside the range on any single marker. On a panel with 50 markers, it is common for a healthy person to have one or two flags.
Some ranges are based on risk, not averages
Cholesterol, blood sugar and vitamin D are different. Their limits come from studies of what happens to people over years, so the cut-off marks where risk starts to climb. An average South African adult can have an LDL cholesterol above the target, which is exactly why the target is set where it is.
Why two labs can give different ranges
Labs use different machines, methods and reference groups, so the same blood can come back with slightly different numbers and ranges. This makes it hard to compare results over time if you switch labs. LifePrint uses published clinical guidelines for key markers, such as the Endocrine Society for testosterone and SEMDSA for HbA1c, so your verdict stays consistent whichever lab you use.
The grey zone
Some results sit just inside or just outside a limit. A fasting glucose of 6.3 mmol/L, a ferritin of 20 ug/L or a testosterone of 10 nmol/L are not clearly normal and not clearly abnormal. Your LifePrint report shows these as a separate grey zone, explains what they could mean, and usually suggests a repeat test rather than alarm.
When a flag does need action
Some results need a doctor soon regardless of how you feel, such as very high potassium, very low haemoglobin, or a blood sugar in the diabetic range. LifePrint marks these clearly and tells you how urgently to follow up. Your report is health information, not a diagnosis, so always discuss flagged results with a registered healthcare practitioner.
This article is general health information and education. It is not a medical diagnosis and does not replace advice from a registered healthcare practitioner who knows your history.
Ready to know your numbers?
Pick a panel, get tested at a lab near you, and receive a clear, personalised report.
Choose your panel