Gout happens when uric acid builds up in your blood and forms crystals in your joints
Gout is caused by monosodium urate crystals—needle-shaped deposits that form when uric acid levels in your blood get too high. Your body produces uric acid when it breaks down purines, which are compounds found in certain foods and also made naturally by your cells. When uric acid accumulates faster than your kidneys can filter it out, crystals settle in joints and surrounding tissue, triggering the sudden, severe inflammation that feels like gout.
The big toe is the most common target, though gout can strike the ankle, knee, wrist, or other joints. The attack happens because your immune system recognizes the crystals as foreign and sends white blood cells to fight them, causing pain, redness, and swelling that can last days or weeks if untreated.
Key Takeaways
- Uric acid builds up when your body produces more than your kidneys can remove, or when your kidneys cannot filter efficiently.
- Purines in red meat, organ meats, certain seafood, and alcohol—especially beer—raise uric acid levels and can trigger attacks.
- Some people have a genetic tendency to develop gout, meaning family members are more likely to have high uric acid.
- Kidney disease, high blood pressure, obesity, and certain medications like diuretics can all increase your gout risk.
- Fructose in sugary drinks and foods can raise uric acid independent of purines, making diet changes important for prevention.
How your kidneys and uric acid production create the problem
Your body makes uric acid as the end product of purine metabolism. Purines come from two sources: the foods you eat and the natural breakdown of your own cells. Normally, your kidneys filter uric acid from your blood and excrete it in urine. But when one of two things happens—your body makes too much uric acid, or your kidneys cannot clear it efficiently—levels rise and crystals form.
About 90 percent of gout cases involve underexcretion, meaning the kidneys are not removing uric acid fast enough, even though production is normal. The remaining 10 percent involve overproduction—your body is making more uric acid than typical. Most people with high uric acid never develop gout; the crystals form only when levels stay elevated long enough and conditions in the joint (like temperature and pH) favor crystal formation.
Foods and drinks that raise uric acid
Purines are concentrated in certain animal products. Red meat, organ meats like liver and kidney, and seafood—especially anchovies, sardines, mussels, and scallops—contain high purine levels. Poultry has moderate amounts, while plant-based proteins like beans and lentils have purines but are less likely to trigger attacks. Dairy products and eggs are low in purines.
Alcohol, particularly beer, raises uric acid in two ways: it slows kidney excretion and beer itself contains purines. Spirits and wine have less impact than beer. Sugary drinks and foods with high-fructose corn syrup increase uric acid independent of purines—fructose metabolism in your liver produces uric acid as a byproduct. This means gout risk rises with sugary beverages even when purines are not involved.
Genetic and medical factors that increase your risk
Gout runs in families. If a parent or sibling has gout, your risk is higher because you may have inherited genes that affect how your kidneys handle uric acid or how much your body produces. Men are more likely to develop gout than women, and the risk rises with age. Women's risk increases after menopause, when estrogen levels drop—estrogen helps kidneys excrete uric acid.
Chronic kidney disease is a major risk factor because damaged kidneys cannot filter uric acid effectively. High blood pressure, obesity, and metabolic syndrome all increase gout risk. Certain medications—particularly diuretics (water pills) used for high blood pressure and heart conditions—reduce uric acid excretion. Chemotherapy can cause a sudden spike in uric acid when cancer cells die and release their contents into the bloodstream.
Why some people develop gout and others with high uric acid do not
Having high uric acid in your blood does not automatically mean you will develop gout. Many people have elevated levels without ever experiencing an attack. The difference lies in whether crystals actually form and trigger inflammation. This depends on joint temperature (cooler joints favor crystal formation, which is why the big toe is vulnerable), the pH of joint fluid, the presence of other proteins that can seed crystal growth, and possibly your individual immune response.
Dehydration, sudden temperature changes, injury to a joint, surgery, and even sudden dietary changes can tip the balance and cause an attack in someone with high uric acid. This is why two people with identical uric acid levels may have very different experiences with gout.
How uric acid levels are measured and what numbers mean
A simple blood test measures your serum uric acid level, reported in milligrams per deciliter (mg/dL). The normal range is typically below 6.8 mg/dL, though labs vary slightly. Levels above 6.8 mg/dL mean uric acid is supersaturated—crystals can form, though they may not. A single high reading does not diagnose gout; your doctor looks at your symptoms, imaging, and sometimes fluid from the affected joint under a microscope to confirm monosodium urate crystals.
Uric acid levels fluctuate day to day based on diet, hydration, and activity. Testing during an acute attack can give a falsely low reading because the attack itself temporarily lowers blood uric acid. For this reason, doctors usually test weeks after an attack has resolved to get an accurate picture of your baseline level.
The difference between acute attacks and chronic gout
A single gout attack does not mean you have chronic gout. One attack can happen to anyone with a temporary spike in uric acid—perhaps from a heavy meal, dehydration, or an illness. Chronic gout means repeated attacks, usually because uric acid stays elevated over time. Without treatment to lower uric acid, attacks tend to become more frequent, last longer, and eventually damage joints permanently.
Long-term high uric acid can also cause tophi—deposits of uric acid crystals that form lumps under the skin, usually on the ears or fingers. These are a sign of poorly controlled chronic gout. Preventing chronic gout requires both managing acute attacks when they happen and, for people with recurrent episodes, taking medication to lower uric acid levels long-term.
Frequently Asked Questions
Can you have gout without high uric acid?
Gout requires uric acid crystals in the joint, so your blood uric acid must be high enough for crystals to form. However, a blood test during an acute attack may show a normal or low level because the attack itself temporarily reduces serum uric acid. If you have gout symptoms, your doctor may diagnose based on the attack itself rather than waiting for a uric acid test.
Does eating purine-rich food always cause a gout attack?
Not always. A purine-rich meal can trigger an attack in someone with high baseline uric acid, but someone with normal uric acid levels can eat the same food without problems. The risk depends on your current uric acid level, kidney function, and how much you eat. Moderation and staying hydrated help reduce attack risk.
Is gout hereditary?
Gout has a strong genetic component. If your parents or siblings have gout, your risk is higher because genes influence how your kidneys handle uric acid and how much your body produces. However, genetics is not destiny—lifestyle factors like diet, weight, and alcohol use also play a major role in whether you develop gout.
Can you get gout from drinking too much water?
No. Drinking more water actually helps prevent gout by diluting urine and helping your kidneys excrete uric acid. Dehydration increases gout risk. The only exception is if you drink large amounts of sugary beverages, which raise uric acid through fructose metabolism.
Do all medications that cause gout work the same way?
No. Diuretics reduce uric acid excretion by the kidneys. Some cancer drugs and immunosuppressants cause gout by increasing cell breakdown, which releases purines. Aspirin at low doses (for heart protection) can also reduce uric acid excretion. Your doctor can discuss whether a medication you take affects gout risk.