What your blood test says about you (and what it doesn’t)
Cholesterol, blood sugar, testosterone, PSA and inflammation: what a routine blood test can tell a man in midlife, what it can’t, and how to get one in the UK.
Reviewed, edited and approved by Editor-in-chief Daniel Sköld · Updated 24 October 2026
Contents
Most of us have a fair idea of what’s going on outside the body. The belt has gone up a notch, the knees have opinions and getting off the sofa now comes with a noise. What’s happening inside is harder to see, and that’s where a small tube of blood comes in.
A routine blood test won’t tell your fortune. It can, though, spot several of the problems that creep up on men between 45 and 64, often years before you feel anything. Here’s what the main results mean, which ones are worth having, and how to get them without spending a fortune.
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What can a blood test actually tell you?
More than you’d think, but not everything. A standard set of tests checks how well some of your organs are working and picks up a few risk factors that cause no symptoms at all until they cause a lot.
The ones that matter most in midlife are pretty ordinary. A cholesterol or lipid profile measures the fats in your blood that help fur up your arteries. HbA1c gives your average blood sugar over the last two to three months, which is how type 2 diabetes and prediabetes are diagnosed. Kidney function is usually reported as eGFR. Liver function tests include enzymes such as ALT and GGT, which can rise with heavy drinking, a fatty liver or some medicines.
A full blood count checks your red cells, white cells and platelets. That’s how anaemia gets picked up, and it matters more for men than many realise. Men don’t lose blood every month, so unexplained anaemia in a middle-aged man is something your GP will want to look into, because it can be a sign of slow bleeding in the gut.
HbA1c is one of the few results worth knowing the numbers for. Under NHS criteria, 42 to 47 mmol/mol counts as prediabetes and 48 or above points to diabetes. Prediabetes isn’t a diagnosis to shrug off, but it is very often reversible with weight loss and more activity. That’s the good news buried in a slightly alarming result.
Can a blood test check your testosterone?
Yes. But this is the test where timing matters most, and plenty of men get it wrong.
Testosterone peaks in the morning and falls through the day, so a sample taken at 4pm can make a perfectly normal man look low. GPs usually ask for an early morning test and, if the result is low, a repeat on another day before reaching any conclusion. Being ill, short of sleep or carrying a lot of extra weight can all push the reading down too.
A low number on its own doesn’t mean much either. Doctors look at it alongside symptoms such as low sex drive, erection problems, fatigue and loss of muscle. If that sounds familiar, talk to your GP before ordering a testosterone kit online. Do the same before you buy anything promising to fix the result.
A blood test is a snapshot, not a verdict. The number matters far less than what you and your GP do with it.
Should men over 50 have a PSA test?
PSA, or prostate-specific antigen, is the test most men have heard of and the least understood. The UK has no national prostate screening programme. Instead, if you’re over 50 you can ask your GP for a PSA test, even with no symptoms. Prostate Cancer UK advises Black men and men with a family history of prostate or breast cancer to start thinking about it from 45, because their risk is higher.
The catch is that PSA is a blunt tool. It can go up because of an infection, an enlarged prostate, recent ejaculation or a long bike ride. A raised level doesn’t mean cancer, and a normal one doesn’t fully rule it out. Your GP should talk through the pros and cons with you before the test, and you’re entitled to that conversation. If you notice changes in how you pee, don’t wait for a test result. Book an appointment.
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Inflammation, vitamin D and the rest
C-reactive protein, or CRP, is the inflammation marker that wellness companies love. It rises when there’s inflammation somewhere in the body: an infection, an injury, an inflammatory condition. It’s useful to doctors chasing a specific problem. But it doesn’t tell you where the inflammation is or why, so a mildly raised CRP on a home kit is more likely to cause worry than give you an answer.
Vitamin D gets tested a lot privately. The NHS doesn’t routinely test it in healthy adults. It simply advises everyone in the UK to consider a daily 10 microgram supplement in autumn and winter, which is cheaper than a test and covers most of us. Ferritin, a measure of stored iron, deserves a mention too. Haemochromatosis, an inherited condition where iron builds up, is relatively common in people of Celtic descent. It’s often found in men in midlife when tiredness, joint pain or odd liver results lead to a blood test.
Thyroid tests (usually TSH) come up when someone is tired, gaining weight or feeling the cold. In other words, half of Britain in February. That’s why GPs order them so often.
How do you get a blood test in the UK?
In England, the free NHS Health Check is the obvious place to start. It’s offered every five years to adults aged 40 to 74 who don’t already have heart disease, diabetes, kidney disease or a few other conditions. It includes a cholesterol test, your blood pressure, height and weight. Blood sugar is checked if your results suggest you’re at risk. You can be invited by your GP surgery or local council, or ask whether you’re eligible.
Scotland, Wales and Northern Ireland have no direct equivalent of the NHS Health Check. If you live there and are worried about your heart or diabetes risk, speak to your GP practice. Your local pharmacy may also offer blood pressure checks.
Beyond that, the NHS will test your blood when there’s a clinical reason. That means symptoms, a family history, or monitoring a medicine. It won’t run a broad panel because you’re curious.
That’s the gap private companies fill, with finger-prick kits you post off and clinic tests that cover anything from cholesterol to a ‘full MOT’. Prices vary a lot, so compare what’s actually included. Bear three things in mind. Finger-prick samples can go wrong if the blood is squeezed out or clots. The more markers you test, the more likely at least one will land just outside the normal range by chance. And your GP may want to repeat a test rather than take a private result at face value.
If anything comes back abnormal, take it to your GP or pharmacist rather than Google. For new or worrying symptoms, use NHS 111. Chest pain, sudden breathlessness or signs of a stroke mean calling 999, not waiting for lab results.
In short
A routine blood test can pick up raised cholesterol, prediabetes and diabetes, kidney and liver problems, anaemia, iron overload and low testosterone, often before you notice any symptoms. In England, the free NHS Health Check for 40 to 74-year-olds covers the most important basics. Men over 50 can ask their GP about a PSA test. Private kits can add more, but the results are only useful if you go through them with your GP and actually act on them.
Adrian Irving writes about health for men 45 and over who would rather do something than worry. Training, weight loss, sleep, cholesterol and blood tests, heart health, testosterone, the prostate, mental health and your sex life – what the evidence says, what's worth trying, and when it's time to see your GP.
One of Midcent's writers. Spotted something? Write to adrian@midcent.uk.
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