How to Read and Understand Your Blood Test Results

You’ve had your blood drawn, waited a few days, and now your results are back. But when you open that pathology report, it can feel like reading a foreign language — a sea of abbreviations, numbers, and reference ranges. Understanding your blood test results doesn’t require a medical degree, but it does require a bit of guidance. This article will walk you through the fundamentals so you can engage meaningfully with your health data.

Understanding the Structure of a Pathology Report

In Australia, pathology results are typically generated by laboratories such as Laverty, QML, or Melbourne Pathology and sent to your referring doctor. Most reports follow a standard structure: the test name, your result, the unit of measurement, and a reference range. Some laboratories also flag results as "High" (H), "Low" (L), or "Abnormal" (A) to draw attention to values outside the expected range.

It’s important to understand that a flagged result does not automatically mean something is wrong. Reference ranges represent the values seen in 95% of a healthy population — meaning 5% of perfectly healthy people will naturally fall outside these ranges. Context is everything.

Key Blood Test Markers and What They Mean

Full Blood Count (FBC)

Your FBC report will include haemoglobin (Hb), white cell count (WCC), and platelets, among other values. Haemoglobin carries oxygen throughout your body — low levels may indicate anaemia, while elevated levels can be seen in dehydration or certain blood disorders. White cell counts reflect immune activity; elevated levels often suggest infection or inflammation, while very low levels may warrant further investigation. Platelets are essential for blood clotting — both high and low counts deserve attention.

Lipid Profile

Your lipid panel will typically show total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides. In Australia, the desirable total cholesterol level is generally below 5.5 mmol/L, with LDL ideally below 2.0 mmol/L for those at high cardiovascular risk. HDL above 1.0 mmol/L for men and 1.3 mmol/L for women is considered protective. Triglycerides should ideally be below 1.7 mmol/L. However, your individual targets may differ based on your overall cardiovascular risk profile.

Blood Glucose and HbA1c

Fasting blood glucose between 3.9 and 5.4 mmol/L is generally considered normal. Levels between 5.5 and 6.9 mmol/L suggest impaired fasting glucose (prediabetes), while 7.0 mmol/L or above on two separate occasions is diagnostic of diabetes. HbA1c provides a longer-term view — a result below 42 mmol/mol (6.0%) is considered normal, 42–47 mmol/mol (6.0–6.4%) suggests prediabetes, and 48 mmol/mol (6.5%) or above indicates diabetes.

Liver Function Tests

The key liver enzymes are ALT, AST, and GGT. Elevated ALT is often the most specific marker for liver cell damage. GGT is particularly sensitive to alcohol consumption and can also be elevated in fatty liver disease and bile duct conditions. ALP (alkaline phosphatase) is less specific to the liver and can be elevated in bone disorders as well. Bilirubin, the yellow pigment in bile, may be elevated in liver disease or conditions such as Gilbert’s syndrome — a common and benign genetic condition.

Kidney Function

Creatinine is a waste product filtered by the kidneys, and your laboratory will use it to calculate your eGFR (estimated glomerular filtration rate). An eGFR above 90 mL/min/1.73m² is considered normal. Values between 60 and 89 may indicate mildly reduced kidney function, while below 60 warrants closer monitoring and further investigation. Urea is another marker of kidney function, though it’s less specific than creatinine.

Thyroid Function

TSH (thyroid-stimulating hormone) is the primary screening test. In most Australian laboratories, the normal range is approximately 0.4–4.0 mIU/L. An elevated TSH suggests your thyroid is underactive (hypothyroidism), while a low TSH suggests overactivity (hyperthyroidism). If TSH is abnormal, your doctor will likely order free T4 and free T3 to further assess thyroid function.

What Reference Ranges Really Mean

Reference ranges are not the same as "optimal" ranges. They are derived statistically from large populations and represent where 95% of healthy individuals fall. This means a result within the reference range is not necessarily optimal for you, and a result slightly outside the range is not necessarily pathological. For example, a ferritin level of 25 µg/L may be within the reference range at some laboratories, but many practitioners consider this suboptimal, particularly for women experiencing fatigue.

This is precisely why tracking your results over time is so valuable. A steady decline in kidney function, even within the normal range, is far more clinically significant than a single snapshot. Platforms like Yearly help you visualise these trends and understand your results in context.

When to Worry — and When Not To

Not every abnormal result requires alarm. Mild elevations in liver enzymes can follow a weekend of heavy eating or drinking. A slightly low white cell count may simply be your normal baseline. Conversely, results that are well within the reference range but trending in the wrong direction deserve attention.

As a general rule, you should follow up with your doctor if any result is flagged as significantly outside the reference range, if multiple markers in the same system are abnormal (for example, both ALT and GGT are elevated), or if you have symptoms that correlate with your results. Never ignore results or assume "no news is good news" — always review your results with your healthcare provider.

Empowering Yourself With Knowledge

Understanding your blood test results puts you in the driver’s seat of your own health. It allows you to ask better questions during medical appointments, make more informed lifestyle choices, and catch potential issues early. In an era of personalised medicine, health literacy is one of the most valuable skills you can develop.

At Yearly, we believe that every Australian deserves to understand their own health data. Our AI-powered platform analyses your blood test results, explains what each marker means, and tracks your trends over time — making the complex simple and the invisible visible.

References

1. Royal College of Pathologists of Australasia (RCPA). "RCPA Manual: Reference intervals." https://www.rcpa.edu.au/Library/Practising-Pathology/RCPA-Manual
2. National Heart Foundation of Australia. "Lipid management guidelines." 2023.
3. The Royal Australian College of General Practitioners (RACGP). "Guidelines for preventive activities in general practice." 10th Edition, 2025.
4. Diabetes Australia. "Diagnosis and monitoring of diabetes." 2024. https://www.diabetesaustralia.com.au
5. Kidney Health Australia. "Understanding your eGFR." https://kidney.org.au/your-kidneys/understand-your-kidneys/egfr