Uric Acid
Also known as: UA
What Does Uric Acid Measure?
Uric acid is a natural waste product produced when the body breaks down purines — chemical compounds found in many foods and also naturally present in human cells. When cells die and are recycled, purines are metabolized into uric acid, which then travels through the bloodstream to the kidneys, where it is filtered and excreted in urine. A blood uric acid test measures the concentration of this compound in the bloodstream, reflecting the balance between how much is being produced and how effectively the kidneys are eliminating it.
Why Does Uric Acid Matter?
Maintaining healthy uric acid levels is important because when levels rise too high (a condition called hyperuricemia), uric acid can form sharp, needle-like crystals that deposit in joints, causing the intensely painful condition known as gout. Chronically elevated uric acid is also associated with kidney stones, chronic kidney disease, high blood pressure, cardiovascular disease, and metabolic syndrome. Conversely, very low uric acid levels (hypouricemia) can signal rare genetic disorders or conditions affecting purine metabolism. Monitoring uric acid helps clinicians diagnose and manage gout, kidney function, and certain metabolic conditions, and it may serve as an early warning marker for cardiometabolic risk.
Normal Ranges
Males
3.4 – 7.0 mg/dL (202 – 416 µmol/L)
Females
2.4 – 6.0 mg/dL (143 – 357 µmol/L)
Children
2.0 – 5.5 mg/dL (119 – 327 µmol/L); varies by age and sex
Causes of High Levels
- Gout or hyperuricemia — overproduction or underexcretion of uric acid leading to crystal deposits in joints
- High-purine diet — excessive consumption of red meat, organ meats, shellfish, and sardines
- Excessive alcohol consumption — especially beer, which is high in purines and impairs renal uric acid excretion
- Chronic kidney disease — reduced kidney filtration capacity leads to uric acid accumulation in the blood
- Obesity and metabolic syndrome — insulin resistance impairs renal uric acid clearance
- Certain medications — diuretics (thiazides, loop diuretics), low-dose aspirin, and some immunosuppressants raise uric acid levels
- Rapid cell turnover — conditions like psoriasis, hemolytic anemia, or chemotherapy-related tumor lysis syndrome release large amounts of purines
Causes of Low Levels
- Xanthinuria — a rare genetic disorder where the enzyme xanthine oxidase is deficient, preventing normal uric acid production
How to Improve Your Uric Acid
Diet
- Reduce purine-rich foods: limit red meat, organ meats (liver, kidneys), and shellfish (shrimp, lobster, anchovies) to lower uric acid production
- Increase water intake to at least 8–10 glasses (2–2.5 liters) per day to support urinary uric acid excretion and reduce kidney stone risk
- Eat more cherries and tart cherry products — anthocyanins in cherries have been shown in studies to reduce uric acid levels and lower gout attack frequency
- Choose low-fat dairy products — low-fat milk, yogurt, and cheese have been shown to lower uric acid and reduce gout risk
- Limit high-fructose corn syrup and sugary beverages — fructose accelerates purine metabolism and raises uric acid levels
- Increase intake of vitamin C-rich foods (citrus fruits, bell peppers, kiwi) — vitamin C promotes renal uric acid excretion
Supplements
- Vitamin C: 500–1500 mg/day — shown in clinical trials to modestly reduce serum uric acid by enhancing renal excretion
- Tart cherry extract: 480 mg/day or 8 oz tart cherry juice twice daily — may reduce uric acid levels and frequency of gout flares
- Quercetin: 500 mg/day — a flavonoid that inhibits xanthine oxidase, the enzyme responsible for uric acid production
Related Biomarkers
Frequently Asked Questions
What uric acid level is considered dangerous or requires treatment?
A uric acid level above 7.0 mg/dL in men or 6.0 mg/dL in women is considered elevated (hyperuricemia). Levels consistently above 8.0 mg/dL significantly increase the risk of gout attacks and kidney stones. Most doctors consider initiating urate-lowering therapy when levels exceed 9.0 mg/dL or when a person has had two or more gout attacks per year, even at lower levels. Always discuss treatment thresholds with your physician, as individual context matters.
Can I eat a normal diet before a uric acid blood test?
Uric acid tests are often performed fasting, but some labs allow non-fasting testing. A recent meal high in purines (red meat, shellfish) can temporarily raise uric acid levels, potentially affecting results. For the most accurate reading, many clinicians recommend fasting for 4–8 hours before the test and avoiding alcohol for 24 hours beforehand. Check with your doctor or lab for specific instructions.
Is high uric acid always gout?
No — high uric acid (hyperuricemia) does not always mean you have gout. In fact, about two-thirds of people with elevated uric acid levels never develop gout. Uric acid must reach a high enough concentration for long enough to form crystals in joints. However, persistent hyperuricemia does increase your lifetime risk of gout, kidney stones, and potentially cardiovascular disease, so it's still worth monitoring and managing even without symptoms.
Why do women generally have lower uric acid levels than men?
Estrogen plays a key role in keeping uric acid levels lower in women of reproductive age. Estrogen promotes the excretion of uric acid by the kidneys (it acts as a uricosuric agent). This is why premenopausal women have significantly lower uric acid levels and much lower rates of gout than men. After menopause, estrogen levels drop and women's uric acid levels rise, leading to increased gout risk — which is why gout in women most commonly appears after age 50.