What It Measures
This test measures the amount of PSA in your blood that is not bound to serum proteins (free-floating). PSA is a protein produced by the prostate gland. A higher proportion of free PSA relative to total PSA generally suggests benign conditions, while a lower proportion raises concern for prostate cancer.
Free PSA measures the percentage of prostate-specific antigen circulating unbound to proteins in the blood. It is used alongside total PSA to help distinguish between prostate cancer and benign prostate conditions like BPH, improving diagnostic specificity and reducing unnecessary biopsies.
Current Value
What High Means
A high free PSA percentage (>25%) is generally reassuring and suggests benign prostatic hyperplasia (BPH) or prostatitis rather than cancer. Elevated free PSA ratios indicate that most PSA is unbound, which is more typical of non-cancerous prostate tissue proliferation. Very high total PSA with high free percentage may still warrant monitoring.
Possible Symptoms
High free PSA percentage itself does not cause symptoms. The underlying BPH may cause urinary frequency, urgency, weak stream, nocturia, incomplete bladder emptying, and difficulty starting urination.
What Low Means
A low free PSA percentage (<10-15%) is associated with increased risk of prostate cancer. Cancer cells tend to produce PSA that binds more readily to blood proteins, leaving less in the free form. A low free-to-total PSA ratio in the context of a borderline total PSA (4-10 ng/mL) significantly increases the probability of malignancy and typically prompts biopsy recommendation.
Possible Symptoms
Low free PSA percentage itself does not cause symptoms. If associated with prostate cancer, symptoms may include difficulty urinating, blood in urine or semen, pelvic pain, bone pain (advanced disease), erectile dysfunction, and unexplained weight loss. Early prostate cancer is often asymptomatic.
Risk Factors
Prostate cancer, benign prostatic hyperplasia (BPH), prostatitis, family history of prostate cancer, age over 50, African American descent, obesity, high-fat diet, exposure to Agent Orange or other environmental toxins.
Actionable Advice
Supplements
- •Saw Palmetto
- •Lycopene
- •Zinc
- •Green Tea Extract (EGCG)
- •Pygeum
- •Beta-Sitosterol
- •Vitamin D3
- •Selenium
- •Stinging Nettle Root
- •Pomegranate Extract
Diet & Lifestyle
- •Eat a diet rich in cruciferous vegetables, tomatoes (cooked for lycopene), and fatty fish
- •Maintain a healthy body weight — obesity is associated with more aggressive prostate cancer
- •Exercise regularly (150+ min/week moderate intensity) — associated with lower prostate cancer risk
- •Limit red and processed meat consumption
- •Reduce dairy intake — high calcium intake may be associated with increased prostate cancer risk
- •Manage stress and get adequate sleep (7-9 hours)
- •Avoid excessive alcohol consumption
- •Discuss screening frequency with your urologist based on personal risk factors
- •Consider annual PSA monitoring starting at age 45-50 (or 40 if high-risk)
Ask AI
Ask questions about your PSA Free results, trends, and what you can do to optimize.
Historical Trend
Related Biomarkers
Resources & Studies
All Readings
| Date | Value | Change |
|---|---|---|
| 2026-01-28 | 0.3 ng/mL | 0.0 |
| 2025-08-25 | 0.3 ng/mL | — |