The PSA Test Explained: What Your Results Actually Mean

Written by Stephen T. Hooper.

This PSA Test Results article is curated from official NHS and other professional resource

protocols to ensure accuracy for our readers.

The PSA Test Explained

If you are over 45, or have a family history of prostate issues, your GP will likely mention the PSA test. It is a simple blood test, but the results are rarely “simple.” Here is the no-jargon breakdown of what the test actually tells you.

What is PSA?

PSA is a protein produced by both normal and cancerous cells in the prostate gland. It is normal to have a small amount of PSA in your blood. However, if your prostate is irritated, inflamed, or contains cancerous cells, it “leaks” more PSA into your bloodstream.

The Problem: PSA is not a “Cancer Test”

This is the most important part to understand: A high PSA level does not mean you have cancer. Common things that can cause a “false positive” (a high reading without cancer) include:

• BPH (Enlarged Prostate): A natural part of ageing for many men.

• Prostatitis: An infection or inflammation of the gland.

• Recent Exercise: Vigorous exercise or cycling in the 48 hours before the test.

• Sexual Activity: Ejaculation within 48 hours of the test.

Conversely, it is possible (though less common) to have a “normal” PSA level and still have prostate cancer.

Should you have the test?

In the UK, there is no automatic screening programme for prostate cancer. Instead, men over 50 have the “informed choice” to request a test.

Pros:

• It can help spot fast-growing cancers before they spread.

• It provides a “baseline” to monitor changes over several years.

Cons:

• It can lead to “over-diagnosis”—treating slow-growing cancers that would never have caused you harm.

• The anxiety of a high reading often leads to invasive biopsies that may turn out to be unnecessary.

The 22PlusY Checklist: Before Your Test

If you decide to go ahead, follow these rules to ensure the most accurate reading:

1. Wait 48 Hours: No ejaculation or vigorous exercise (especially cycling) for two days before the blood draw.
2. Check for Infection: If you have symptoms of a urinary tract infection (stinging when you pee), wait until it’s cleared before testing.
3. Know Your Number: Ask your GP for the specific nanograms per millilitre ($ng/ml$) figure, not just “it’s fine.”

It’s not a simple ‘Yes’ or ‘No’

In the UK, the NHS uses age-specific “referral thresholds.” Because PSA naturally rises as the prostate grows with age, a “high” reading for a 50-year-old is perfectly “normal” for a 70-year-old.

PSA Levels by Age: What the Numbers Mean

If your results are back, you will see a figure measured in nanograms per millilitre (ng/ml). While every lab is slightly different, the following are the standard UK “Referral Thresholds” used by the NHS to decide if further investigation (like an MRI) is needed.

NHS PSA Referral Thresholds (The “Red Flag” Numbers):

• • • Aged below 40: Use clinical judgement

    • Aged 40–49: 2.5 ng/ml or higher

    • Aged 50–59: 3.5 ng/ml or higher

    • Aged 60–69: 4.5 ng/ml or higher

    • Aged 70–79: 6.5 ng/ml or higher

    • Aged 79 and up: Use clinical judgement

3 Critical Rules for Interpreting Your Result:

1. Velocity Matters More Than the Number: A single high reading is less important than how fast the number is rising. If your PSA was 1.5 last year and is 2.8 this year, that “jump” (called the ‘PSA Velocity’) is a bigger red flag than the number itself.
2. The “Grey Zone”: Most doctors consider the range between 4.0 and 10.0 ng/ml the “Grey Zone.” In this range, about 25% of men will have cancer, but 75% will have a benign condition like an enlarged prostate (BPH).
3. The “Free PSA” Ratio: If your total PSA is high, your doctor may look at “Free PSA.” A lower ratio of free-to-total PSA can sometimes indicate a higher risk of cancer.
4. If you are seeing your doctor, take along a copy of our FREE GP Consultation Aid below. This will help you to keep focused during your appointment.

PSA Spikes: What Can Cause a “False Positive”?

A high PSA reading is a “red flag,” but it isn’t always a sign of cancer. The prostate is a sensitive gland; any irritation or activity in the pelvic area can cause it to leak PSA into your bloodstream.

To ensure your test is as accurate as possible, you should avoid the following “PSA Interferences” for at least 48 hours before your blood draw:

• Vigorous Exercise: Specifically cycling. The pressure of a bike saddle against the perineum directly irritates the prostate. Heavy weightlifting or long-distance running can also cause a temporary spike.

• Sexual Activity: Ejaculation within 48 hours of the test can significantly raise PSA levels.

• Urinary Tract Infections (UTIs): Any infection in the bladder or urinary tract will cause inflammation in the prostate. If you’ve had stinging or frequent urination lately, wait until the infection is cleared before testing.

• Digital Rectal Examination (DRE): If a doctor has performed a physical exam of the prostate recently, you should wait a few days before having your blood taken.

• Recent Procedures: If you have recently had a catheter fitted or a bladder biopsy, your PSA will be artificially high for several weeks.

Related articles:

Article about Prostate Cancer – https://22plusy.com/prostate-cancer-better-safe-than-sorry/

Testicular cancer symptoms guide – 7 Vital FAQs About Testicular Cancer

Self examination guide – https://22plusy.com/22plusy-com-testicular-self-examination-guide/

Need Support or More Info?

If you have concerns about your results or symptoms, these UK organisations provide expert, confidential support.

• Prostate Cancer UK

  • Best for: Specialist nurse phonelines and a “Risk Checker” tool.

• Movember (UK)

  • Best for: General men’s health, mental health resources, and prostate research.

• Macmillan Cancer Support

  • Best for: Practical, financial, and emotional support following a diagnosis.

• NHS 111 Online

  • Best for: Immediate advice if you have symptoms and can’t reach your GP.