Understanding Your Uric Acid Levels

What is uric acid?

Uric acid is a natural waste product that your body creates when it breaks down substances called purines. Purines come from two sources: your own cells (as they turn over naturally) and certain foods you eat. Your kidneys are responsible for filtering uric acid out of your blood and excreting it in your urine.

In most people, this system works smoothly. But when your body produces too much uric acid — or your kidneys don’t clear enough of it — levels build up in the blood. This is called hyperuricemia. Over time, elevated uric acid can lead to the formation of monosodium urate crystals in your joints and soft tissues, which is the underlying cause of gout.

What’s the target?

For patients with gout, the goal of treatment is to keep your uric acid level below 6 mg/dL — consistently, over time. This threshold is important because it’s below the level at which urate crystals can form. At sustained levels below 6, existing crystals gradually dissolve, and new ones stop forming.

• For patients with tophaceous gout — visible or palpable deposits of urate crystals under the skin — the target is even lower: below 5 mg/dL. This accelerates the process of crystal dissolution.
• A single reading below 6 doesn’t mean you’re done. The goal is to stay below this threshold long-term, which is why we check levels periodically even when things are going well.

Reaching your target uric acid level is the single most important factor in preventing future gout flares and joint damage. Medication is the most reliable way to get there for most patients.

Why uric acid levels fluctuate

Your uric acid level is not a fixed number — it moves up and down based on a variety of factors:

• Hydration: Dehydration concentrates uric acid in the blood. Staying well-hydrated helps your kidneys clear it more efficiently.
• Diet: Certain foods and drinks can raise uric acid acutely. More on this below.
• Medications: Diuretics (water pills) — especially hydrochlorothiazide — are a common cause of elevated uric acid. Low-dose aspirin can also raise levels modestly.
• Kidney function: As kidney function declines, uric acid clearance decreases. This is why gout becomes more common with age and in patients with chronic kidney disease.
• Illness and surgery: Physiologic stress — including hospitalization, surgery, and acute illness — can cause uric acid levels to swing in either direction.
• Weight changes: Rapid weight loss, including crash diets and bariatric surgery, can temporarily spike uric acid levels due to increased cell turnover.

The treatment paradox

Here is something that catches many patients off guard: when you start a urate-lowering medication like allopurinol or febuxostat, your uric acid level may temporarily rise or fluctuate — and you may get a gout flare.

This is expected and does not mean the medication isn’t working. When uric acid levels shift — even in the right direction — existing crystals in your joints can become destabilized, triggering inflammation. This is why your doctor prescribes prophylactic anti-inflammatory medication (usually colchicine or an NSAID) for the first several months of urate-lowering therapy.

Do not stop your urate-lowering medication because of a flare. Stopping and restarting creates the very uric acid fluctuations that provoke flares. Stay the course.

The flare-day misconception

One of the most common misconceptions about gout: a normal uric acid level during an active flare does not rule out gout.

During a flare, your body’s inflammatory response can actually pull uric acid levels down temporarily. This means that if we check your uric acid while your toe is red, hot, and swollen, the number may come back in the normal range — and that can be misleading. We know to interpret this carefully. The best time to assess your baseline uric acid level is between flares, when inflammation is quiet.

What about diet?

Diet plays a role in uric acid levels, but it’s a smaller role than most patients expect. Dietary changes alone typically lower uric acid by only about 1 mg/dL — which is meaningful, but usually not enough on its own for patients who need treatment.

That said, some dietary modifications are evidence-based and worth adopting:

• Limit alcohol — beer is the worst offender because it contains purines and impairs uric acid excretion. Liquor has a moderate effect. Wine appears to have the least impact, though moderation still applies.
• Limit sugary beverages — drinks sweetened with high-fructose corn syrup (sodas, fruit juices with added sugar) raise uric acid through fructose metabolism. This is an underappreciated contributor.
• Moderate high-purine foods — organ meats (liver, kidney), certain shellfish, and red meat are the highest-purine foods. You don’t need to eliminate them entirely, but reducing intake is reasonable.
• Dairy may help — low-fat dairy products have been associated with modestly lower uric acid levels and may have a mild protective effect.
• Cherries — tart cherries and cherry extract have evidence supporting a modest uric acid–lowering effect and may reduce flare frequency. Fresh, frozen, dried, or as juice concentrate — all forms appear beneficial. This is one of the few “home remedies” with actual clinical data behind it.
• Hydration matters — drinking adequate water helps your kidneys do their job. There’s no magic number, but aim for enough that your urine is light-colored.

For most patients with gout, medication is the primary driver of reaching your uric acid target. Diet is a supporting player, not the star. Don’t let guilt about what you eat replace a conversation with your doctor about treatment.

When do we check uric acid?

• At diagnosis — to establish your baseline level (ideally between flares)
• Every 2–4 weeks while adjusting urate-lowering therapy — this is how we titrate your dose to reach the target
• Every 6–12 months once you’re at goal — to make sure levels remain in range
• If you have a breakthrough flare — though we interpret the result with the caveat above

Your uric acid level is one of the few numbers in rheumatology where we have a clear, evidence-based target. Reaching and maintaining that target is the most important thing you can do to take control of your gout.

This handout is provided for educational purposes and does not replace individualized medical advice. Always follow the specific instructions given by your rheumatologist.