Uric acid is produced when your body breaks down compounds called purines, which are found in your cells and in many foods. Your body generates roughly 300 to 400 mg of uric acid per day, most of it made in the liver. What determines your blood level isn’t just how much you produce, though. It’s the balance between production and elimination. When that balance tips in either direction, uric acid accumulates.
How Your Body Makes Uric Acid
Purines are building blocks of DNA and RNA, so every cell in your body contains them. When cells naturally turn over and die, those purines get recycled or broken down. The final step of that breakdown involves an enzyme called xanthine oxidase, which converts a substance called hypoxanthine into xanthine, and then xanthine into uric acid. That’s the end of the line for purine metabolism in humans.
Most other mammals have an additional enzyme that breaks uric acid down further into a more easily excreted compound. Humans lost the gene for that enzyme millions of years ago, which means uric acid is our final waste product. It dissolves in the blood, travels to the kidneys, and gets filtered out in urine. The kidneys handle about 60 to 70% of uric acid removal. The remaining 30 to 40% is eliminated through the intestines, where gut bacteria break it down further.
Normal Uric Acid Levels
For adult men, the typical reference range is 4.0 to 8.5 mg/dL. For adult women, it’s 2.7 to 7.3 mg/dL. Children generally fall between 2.5 and 5.5 mg/dL. Levels above 6 mg/dL cross the physiological saturation threshold, meaning uric acid starts to crystallize in body tissues. That’s why the treatment target for gout is below 6 mg/dL. Levels above 12 mg/dL are considered potentially dangerous. Older adults tend to run slightly higher than younger adults.
Foods That Raise Uric Acid
Purine-rich foods are the most direct dietary trigger. Organ meats like liver, kidney, and sweetbreads top the list. Red meat (beef, lamb, pork) is moderately high in purines. Among seafood, anchovies, sardines, shellfish, and codfish are the biggest contributors.
One important nuance: vegetables that contain purines, such as asparagus, spinach, and green peas, do not appear to raise gout risk. Studies consistently show that plant-based purines behave differently in the body than animal-based ones, so cutting vegetables to lower uric acid is unnecessary.
How Fructose Drives Up Uric Acid
Sugar-sweetened drinks and foods high in fructose raise uric acid through a completely different mechanism than purine-rich meats. When fructose enters the liver, an enzyme rapidly adds a phosphate group to it. That process burns through the cell’s energy reserves so quickly that it depletes a molecule called ATP. The leftover fragments of ATP then feed directly into the purine breakdown pathway, generating uric acid as a byproduct.
What makes fructose especially problematic is that this process has no built-in brakes. Glucose metabolism is self-regulating: when the cell has enough energy, the process slows down. Fructose metabolism keeps going regardless, producing uric acid and also raw materials for fat production. This is one reason high-fructose diets are linked to both elevated uric acid and high triglycerides.
Alcohol’s Double Effect
Alcohol raises uric acid through two simultaneous mechanisms: it increases production and reduces excretion. During alcohol metabolism, the liver produces lactic acid, which competes with uric acid for excretion through the kidneys. The result is that uric acid backs up in the bloodstream.
Beer is the worst offender among alcoholic drinks. It’s rich in purines and also contains D-amino acids that get converted into additional uric acid. So beer both floods the body with raw material for uric acid production and blocks the kidney’s ability to clear it. Spirits contain fewer purines but are high in ethanol, which still drives lactic acid production and inhibits uric acid excretion.
Wine occupies an interesting middle ground. It contains ethanol, but red wine in particular is also rich in polyphenols, plant compounds that may reduce oxidative stress and partially inhibit xanthine oxidase, the enzyme responsible for producing uric acid. This may explain why wine shows a weaker association with gout risk than beer or spirits.
When the Kidneys Don’t Clear Enough
Defective kidney handling of uric acid is one of the most common underlying causes of high levels. Even if your body produces a normal amount of uric acid, sluggish excretion can tip the balance. Several factors impair the kidney’s filtering ability.
Chronic kidney disease reduces the overall filtering rate, meaning less uric acid gets removed per hour. Dehydration concentrates the blood and reduces urine output, slowing clearance. Reduced intestinal excretion is also an underrecognized cause of high uric acid, since a meaningful share of elimination happens through the gut.
Genetics and Uric Acid Transport
Your genes play a significant role in determining baseline uric acid levels. Three genes have the strongest influence. The first, SLC2A9, codes for a transporter protein in the kidney that helps move uric acid across cell membranes. The second, SLC22A12, produces a transporter called URAT1 that sits on the inner surface of kidney tubule cells and reabsorbs uric acid back into the blood. The third, ABCG2, handles uric acid secretion, pushing it out of the body.
Variants in any of these genes can shift the balance. A version of URAT1 that reabsorbs too aggressively, or a version of ABCG2 that secretes too weakly, can leave you with chronically elevated levels regardless of diet. This is a major reason why some people develop gout while eating modestly, while others eat purine-heavy diets without issue.
Medications That Raise Uric Acid
Several common drug classes can push uric acid levels up as a side effect:
- Diuretics (water pills): Both loop and thiazide diuretics increase uric acid reabsorption in the kidneys and cause volume contraction, concentrating uric acid in the blood. These are among the most frequent medication-related causes of high uric acid.
- Low-dose aspirin: Daily aspirin in the 60 to 300 mg range reduces uric acid excretion by facilitating its reabsorption in the kidney. Interestingly, higher doses of aspirin have the opposite effect.
- Immunosuppressants: Cyclosporine, commonly used after organ transplants, increases uric acid reabsorption while also reducing the kidney’s filtering rate.
- Testosterone replacement therapy: Raises uric acid in a dose-dependent way and reduces kidney excretion.
- Chemotherapy drugs: Can cause a rapid surge in uric acid by destroying large numbers of cells at once, releasing their purine contents into the bloodstream.
Certain tuberculosis medications, particularly pyrazinamide, are also potent uric acid retention agents. If you’re taking any of these medications and notice joint pain or swelling, your uric acid levels may be worth checking.
Insulin Resistance and Uric Acid
Metabolic health has a strong, often overlooked connection to uric acid. When your body becomes resistant to insulin, meaning cells don’t respond well to the hormone and the pancreas compensates by producing more, the excess insulin directly affects the kidneys. High insulin levels ramp up the activity of the same URAT1 and GLUT9 transporters that reabsorb uric acid, essentially telling the kidneys to hold onto more of it. Insulin resistance also increases the activity of xanthine oxidase, boosting uric acid production at the source.
This creates a feedback loop. High uric acid itself appears to worsen insulin resistance, and insulin resistance drives uric acid higher. It’s one reason why elevated uric acid commonly clusters with obesity, high blood pressure, high triglycerides, and type 2 diabetes, a pattern known as metabolic syndrome. Addressing insulin resistance through weight loss, exercise, and reducing refined carbohydrates can lower uric acid levels even without specific uric acid medications.