Gout develops when uric acid builds up in your blood and forms sharp crystals inside a joint, triggering intense inflammation and pain. About 5.2% of adult men and 2.7% of adult women in the United States have it, with rates climbing to 7% or higher in older men. The buildup happens through a combination of what your body produces, what your kidneys can clear, what you eat and drink, and the genes you inherited.
How Uric Acid Builds Up
Your body constantly breaks down compounds called purines, which come from two sources: your own cells as they turn over, and the food you eat. The final step of purine breakdown in humans produces uric acid. Most mammals have an enzyme that breaks uric acid down further into a harmless substance, but humans lost that enzyme through evolution. That means uric acid is the end of the line for us, and the only way to get rid of it is through the kidneys and, to a lesser extent, the gut.
Your kidneys filter uric acid from the blood, but they reabsorb roughly 90% of it back into the bloodstream. Only about 10% actually leaves in your urine. This reabsorption is tightly controlled by a set of transporters in the kidney’s filtering tubes. When the balance tips toward too much reabsorption or too little secretion, uric acid accumulates in the blood. Once blood levels stay elevated long enough (a condition called hyperuricemia), the stage is set for crystals to form.
Why Crystals Form in Specific Joints
Uric acid doesn’t crystallize everywhere in the body at the same rate. It tends to form crystals in cooler, peripheral joints like the big toe, ankles, and fingers. Lower temperatures reduce uric acid’s solubility, making it easier for crystals to precipitate out of the fluid surrounding the joint. The sodium naturally present in joint fluid also lowers solubility at physiologically relevant concentrations, and the slightly alkaline pH of joint fluid (around 7 to 7.5) further favors crystal formation.
This is why the classic first gout attack hits the base of the big toe. It’s one of the coolest spots in the body, far from the core, and the combination of temperature, sodium concentration, and pH creates ideal conditions for crystals to settle.
Foods That Raise Uric Acid
Purine-rich foods directly increase the amount of uric acid your body produces. The highest concentrations are found in organ meats and certain seafood. Anchovies, for example, contain about 321 mg of purines per 100 grams. Liver can reach 220 mg per 100 grams. The finfish and shellfish category spans an enormous range, from under 8 mg to as high as 1,400 mg per 100 grams depending on the species. Pork products range from 141 to 448 mg per 100 grams depending on the cut and preparation. Regular beef cuts fall between 77 and 123 mg per 100 grams.
Fructose deserves special attention because it’s the only carbohydrate that generates uric acid during its own metabolism. When your liver processes fructose, it rapidly burns through the cell’s energy stores. This triggers a cascade that breaks down the cell’s own energy molecules into purines, which then convert to uric acid. Unlike glucose metabolism, this process has no built-in brake, so large doses of fructose (from sugary drinks, fruit juice concentrates, or foods sweetened with high-fructose corn syrup) can spike uric acid levels independently of any purine content in the food itself.
How Alcohol Increases Risk
All types of alcohol raise gout risk, but not equally. Beer carries the highest risk because it contains both ethanol and high levels of guanosine, a purine that the body absorbs easily. Drinking more than two to four beers in a 24-hour period raises the risk of a gout flare by about 75%. Hard liquor at similar quantities increases the risk by roughly 67%. Wine was once thought to be safer, but consuming just one to two servings over a 24-hour period more than doubles the risk of a recurrent attack.
Alcohol raises uric acid through multiple routes. Ethanol itself accelerates purine breakdown in the body, and it also impairs the kidneys’ ability to excrete uric acid. Beer adds a direct purine load on top of that.
Genetics and Uric Acid Clearance
Your genes play a substantial role in determining how efficiently your kidneys handle uric acid. Large genetic studies have identified two genes with particularly strong links to gout risk. One gene controls a transporter responsible for moving uric acid out of kidney cells and back into the blood. Certain variants of this gene are dramatically more common in people with gout. In one study, a specific high-risk variant appeared in 29% of gout patients compared to just 5% of controls, more than tripling the odds of developing the disease.
A second gene controls a transporter that secretes uric acid out of the body through both the kidneys and the gut. Dysfunctional versions of this transporter inhibit uric acid secretion from both routes, effectively trapping more uric acid in the bloodstream. If you have a family history of gout, there’s a reasonable chance you’ve inherited variants that make your kidneys less efficient at clearing uric acid, even if your diet is moderate.
Medications That Raise Uric Acid
Several common medications can push uric acid levels into the danger zone. Diuretics (water pills) are the most widely prescribed culprits. They increase uric acid reabsorption in the kidneys, and current hypertension guidelines list gout as a reason to avoid them when possible. Loop diuretics, the more powerful type often prescribed for heart failure, carry a higher gout risk than the milder thiazide diuretics used for blood pressure.
Low-dose aspirin also reduces the kidneys’ ability to excrete uric acid. Cyclosporine, an immune-suppressing drug used after organ transplants and for certain autoimmune conditions, is another known trigger. If you’ve started a new medication and notice joint pain or swelling, the drug itself could be contributing to rising uric acid levels.
Insulin Resistance and Related Conditions
Gout doesn’t exist in isolation. It clusters with metabolic syndrome, type 2 diabetes, high blood pressure, and obesity. The link isn’t coincidental. Insulin resistance, the core feature of metabolic syndrome, directly impairs the kidneys’ ability to clear uric acid. Studies show that as insulin resistance increases, uric acid clearance decreases proportionally. High insulin levels also cause the kidneys to hold onto more sodium, and sodium retention further reduces uric acid excretion.
This helps explain why gout rates have climbed alongside obesity rates. Carrying excess weight increases insulin resistance, which reduces uric acid clearance, which raises blood levels, which eventually leads to crystal deposits in the joints. Losing weight can improve insulin sensitivity and, over time, lower uric acid levels.
Who Gets Gout
Men develop gout far more often than women, largely because estrogen helps the kidneys excrete uric acid. Women’s risk rises after menopause as estrogen levels drop. Gout prevalence reaches about 7% in older men and roughly 5% in older women. The typical first attack occurs in middle age for men and somewhat later for women.
Beyond sex and age, the strongest risk factors are a combination of genetic predisposition, high body weight, regular alcohol use (especially beer), a diet heavy in red meat and seafood, fructose-sweetened beverages, and medications like diuretics. Most people who develop gout have more than one of these factors working simultaneously. Uric acid creeps upward over years before the first crystal deposits cause a noticeable flare, which is why gout often seems to appear suddenly even though the underlying buildup has been progressing for a long time.