The Blood Test Questions Australians Ask Us Most

We have arranged blood tests for more than 5,000 Australians. Do that long enough and you hear the same questions over and over, at the collection centre, in our inbox, and in the searches that bring people to us. So we wrote them down and answered them properly. No jargon, no upsell, just what we would tell a mate who asked.

Getting tested

How long will my results take?

Usually 24 to 48 hours from the moment your blood is drawn. A few specialised tests take longer, and we will tell you if yours is one of them, but for the vast majority you will have a full report in your inbox within two days, checked by an AHPRA-registered doctor. This is the question we get more than any other, and the honest answer is that it is faster than most people expect.

Do I really need to fast?

Only for some tests. If your panel includes a fasting glucose or a cholesterol profile, fast for 8 to 12 hours first, water is fine, and the morning is easiest. Thyroid, a full blood count, most hormones and plenty of other markers do not need it at all. People often over-fast just in case and only make the morning harder than it had to be. If any part of your test needs it, we flag it when you order.

Do I need a referral from my GP?

No, and that is the whole point of what we do. You order online, we email you the pathology form, and you walk into any of 3,300+ collection centres around the country. No appointment, no referral, no sitting in a waiting room to be told you can have the test you already knew you wanted. Take the results to your GP afterwards if you like. Plenty of people do.

How often should I test?

For a general check-in, once a year suits most people. Test more often if you are chasing something specific, tracking a change you have made to your training or diet, or keeping an eye on a treatment like thyroid or hormone therapy. There is no prize for testing constantly, but there is real value in a yearly baseline you can measure yourself against as you get older.

Making sense of your results

What can a blood test actually tell me?

More than most people realise. From one draw we can see how your liver, kidneys and thyroid are working, whether you are low in iron, B12 or vitamin D, how your blood sugar and cholesterol are tracking, where your hormones sit, and whether inflammation is brewing. What shows up comes down to the panel you pick. A broad health check sweeps across all of it, a targeted test goes deep on one thing.

How do I read my own results?

Every marker on your report sits next to a reference range, the band considered normal. Inside the range is generally reassuring. Outside it is a nudge to look closer, not a verdict. Two things trip people up: ranges differ slightly between labs, and some markers only make sense in relation to others, so a normal-looking number can still be part of an off pattern. If something is flagged, or it does not match how you feel, that is the moment to talk to a doctor rather than a search engine.

The markers people ask us about most

This is where most of the questions land. These are the ones that come up again and again.

Cholesterol, and the markers beyond it

Cholesterol is the one everyone knows. In Australia the usual reference point for total cholesterol is under 5.5 mmol/L, with a lower LDL (the "bad" one) and a higher HDL (the "good" one) being the shape you want, though your real targets depend on your overall risk. The lifestyle levers are the familiar ones: less saturated fat, more movement, a healthy weight, no smoking.

But cholesterol is also where we get our most interesting questions, because people are starting to look past the standard panel. Two markers come up a lot now.

Lipoprotein(a), or Lp(a). A cholesterol-carrying particle you inherit. It is largely set by your genes, it barely moves with diet, and a standard cholesterol test does not measure it. For some people it is the single biggest piece of their heart-risk picture and they have no idea, because nobody ever checked. Because it is roughly 80 to 90 percent genetic, you usually only need to test it once in your life.

ApoB. Where LDL estimates how much cholesterol you are carrying, ApoB counts the actual number of harmful particles doing the damage. Around 1 in 6 people have normal LDL but raised ApoB, so a standard test can wave them through while the risk is real. A lot of clinicians now treat ApoB as the sharper single number. If you have a family history of heart disease and a normal cholesterol result that never quite reassured you, these are the two markers worth knowing about.

Blood sugar: HbA1c and glucose

Two ways of looking at the same thing. A fasting glucose is a snapshot of your blood sugar right now, normally somewhere around 4.0 to 5.4 mmol/L. HbA1c is the bigger picture, your average blood sugar over the last three months or so, which is why it is the go-to for spotting prediabetes and diabetes. It does not need fasting, and it does not care that you were good the day before the test, which is exactly what makes it useful.

CRP and inflammation

CRP (C-reactive protein) measures inflammation. A high reading means something is inflamed somewhere, which might be as harmless as a cold you are shaking off or as meaningful as a long-running condition. A more sensitive version, hs-CRP, gets used when working out heart-disease risk. On its own CRP will not tell you the cause, but it is a useful flag that something deserves a closer look.

Iron and ferritin

If you are tired all the time, this is often where the answer is hiding. Ferritin measures your iron stores, the reserve tank, and it can run low well before a standard test would call you anaemic. It is one of the most common things we see behind persistent fatigue, particularly in women. Iron is a good example of why one number is not enough: your full blood count can look fine while your ferritin quietly tells the real story.

Testosterone

One of the most asked-about markers we handle, and one of the most misunderstood. The short version is that for adult men a total testosterone of roughly 8 to 30 nmol/L is the usual range, but the total on its own can mislead you, because how you feel depends on your free testosterone, the active part your body can actually use. We have written the full picture in how to check your testosterone levels and free vs total testosterone. If you want it measured properly, the testosterone test covers total, free, SHBG and the free androgen index, and the male hormone profile adds oestradiol, LH and FSH for the full context.

Thyroid and TSH

The other hormone we field endless questions about, usually from people dealing with fatigue, weight changes or feeling the cold. The first-line test is TSH, and it is famously back-to-front: a high TSH points to an underactive thyroid, a low TSH to an overactive one. TSH on its own is a solid screen, but if it comes back off, or your symptoms are loud, a full thyroid test adding Free T4, Free T3 and antibodies is what actually explains why.

The other hormones people ask about

Testosterone and thyroid get the most attention, but they are not the whole hormone story, and people increasingly ask about the rest. Oestradiol, the main oestrogen, matters for women and men. Cortisol, your stress hormone, comes up constantly with anyone dealing with burnout, broken sleep or stubborn weight. Prolactin is worth checking when testosterone is low or cycles are irregular. And two calculated values round out the picture, free testosterone and the free androgen index, which estimate how much of your testosterone is actually active. You can check any of these on their own or together with our Create Your Own test, or as part of the male hormone profile. The full range sits under hormone blood tests.

The full blood count

The workhorse. A full blood count looks at your red cells (and the haemoglobin that carries your oxygen), your white cells (your immune system) and your platelets (which handle clotting). It is common, inexpensive and genuinely useful, a broad snapshot that can flag anaemia, infection and more in a single test. If you only ever ran two tests, this and a metabolic panel would tell you a great deal.

At-home testing kits

Here is a shift we did not fully see coming: a steady move toward at-home testing. It is not huge yet, but it is growing, and the reasons people give are consistent. Convenience is the obvious one. But more than that, people want the kind of in-depth, functional testing a standard GP visit rarely covers, the advanced markers that let them build a baseline, understand where their health actually sits, and work out what to change next. This is data you generally cannot get through the usual channels, and once people have it, they tend to come back for more.

The one we get asked about most is gut health. Our Complete Microbiome Mapping uses DNA-based testing to map the bacteria in your gut and flag imbalances linked to digestion, immunity and inflammation. For a lot of people it is the doorway into this whole style of testing. From there the interest spreads into the markers you genuinely cannot get from a normal visit:

• Genetic methylation testing, a systems-level look at how your genes influence energy, detoxification, hormone metabolism and focus, from a simple saliva sample. See our genetic tests.
• Biological age, which measures how your cells are actually ageing compared to your birthday, and lets you track it year over year.
• Sleep and stress, mapping your cortisol and melatonin patterns to explain why your energy and recovery feel off.
• Vaginal microbiome, a detailed profile for women wanting to understand recurrent issues and their reproductive health.

What ties these together is the same thing running through this whole article: people want the full picture of their own health, in depth and on their own terms, and they want it to actually change what they do next. At-home kits are simply the most convenient way we have found to put that level of insight in someone's hands. You can see the full range under at-home testing kits.

How we think about all this

If there is one thread running through these questions, it is that people want to understand their own bodies, and for a long time that was made harder than it needed to be. A number on a page stops being scary the moment someone explains it. That is the job we have taken on: get you the test without the gatekeeping, then help you make sense of what comes back. All of this is general information rather than personal medical advice, and anything that looks off is worth a proper conversation with your doctor. But the questions themselves, keep asking them. They are how you get to know the one body you have.