Walnuts are one of the safest nuts you can eat if you have gout. They contain roughly 20 mg of purines per 100 grams, which is low enough that even gout-conscious diets can include them comfortably. Beyond just being low-risk, walnuts contain compounds that may actively work against uric acid buildup, though the human evidence for a direct protective effect is still tentative rather than settled.
Why Walnuts Rank So Low on the Purine Scale
Purines are the compounds your body breaks down into uric acid. When uric acid accumulates faster than your kidneys can clear it, crystals form in your joints and trigger the searing pain of a gout flare. Foods vary wildly in how many purines they deliver, and walnuts land near the bottom of the scale. A 2024 review found that walnuts contain about 19.6 mg of purines per 100 grams. For context, almonds come in at 31 mg per 100 g and peanuts at 49.1 mg. A standard handful of walnuts, roughly 30 grams, delivers under 6 mg of purines, which is negligible by any dietary standard.1PubMed Central. Do Nuts Contain a Lot of Uric Acid, and Are Safe for a Low-Purine Diet?
To put that in perspective, a serving of organ meat like liver can contain several hundred milligrams of purines, and even a moderate portion of beef or sardines can exceed 100 mg. A handful of walnuts contributes so little to your daily purine load that it barely registers. If you’re tracking purines to manage gout, walnuts are one of the easiest foods to fit in without concern.
What Eating Walnuts Actually Does to Uric Acid Levels
Low purine content is reassuring, but people with gout care about what happens to their uric acid after eating. A controlled feeding trial compared a high-walnut diet to a control diet in adults and found no significant change in serum uric acid levels between the groups. Blood pressure, cholesterol markers, and inflammatory markers were also unaffected.2British Journal of Nutrition. Effects of a high walnut and high cashew nut diet on selected markers of the metabolic syndrome: a controlled feeding trial A separate study measuring uric acid after a walnut-based test meal found that uric acid levels held steady over a five-hour window, though markers of oxidative stress improved modestly, with antioxidant capacity rising and lipid oxidation dropping.3PubMed Central. Effect of a walnut meal on postprandial oxidative stress and antioxidants in healthy individuals
The fact that walnuts don’t raise uric acid is itself good news, because some foods that seem harmless can still spike levels. But there’s also a hint they may push things in the right direction. A study of young adults found that those with the highest walnut intake had about a 22% lower odds of having high uric acid compared to those who ate the fewest walnuts, though this result didn’t quite reach the threshold researchers set for statistical confidence.4PubMed Central. Nut intake and hyperuricemia risk in young adults In the same study, pine nuts showed a clearer 29% reduction in risk that did reach significance. So walnuts appear safe and may be mildly protective, though the evidence isn’t strong enough to call them a treatment.
Compounds in Walnuts That Work Against Uric Acid
Uric acid is produced in your body by an enzyme called xanthine oxidase, and this is the same enzyme that gout medications like allopurinol target. It turns out that walnut extracts, from the fruit, stems, and leaves, can inhibit this enzyme in lab settings. Researchers found that most walnut extracts achieved greater than 50% inhibition of xanthine oxidase activity at the concentrations tested.5International Journal of Food Science & Technology. The antioxidant activities and the xanthine oxidase inhibition effects of walnut (Juglans regia L.) fruit, stem and leaf That’s a promising signal, even though lab concentrations don’t translate directly to what happens when you eat a handful of walnuts.
One specific compound driving this effect is ellagic acid, a polyphenol found in walnuts, pomegranates, and berries. Research confirmed that ellagic acid acts as a reversible inhibitor of xanthine oxidase, entering the enzyme’s active site and slowing its ability to convert purines into uric acid. Animal studies verified that ellagic acid has a real anti-hyperuricemia effect in living organisms, not just in a test tube, though its potency is weaker than allopurinol.6PubMed Central. Xanthine oxidase inhibitory kinetics and mechanism of ellagic acid: In vitro, in silico and in vivo studies Walnuts are among the richest dietary sources of ellagic acid, which makes this finding particularly relevant. Nobody is suggesting that eating walnuts replaces gout medication, but the compounds in walnuts at least push in the right metabolic direction.
Walnut Peptides and Purine Absorption
A newer line of research has zeroed in on specific peptides, short chains of amino acids, that form when walnut protein is broken down during digestion. Lab experiments showed that certain walnut-derived peptides significantly reduced both the production and excretion of uric acid in intestinal tissue. One peptide in particular reduced the transport efficiency of hypoxanthine, a precursor to uric acid, in cell models. Molecular analysis suggested these peptides may physically bind to hypoxanthine in a way that interferes with its absorption.7Food Bioscience. Walnut peptide reduce uric acid production by non-covalent binding to hypoxanthine in vitro
This is early-stage science, conducted in lab dishes and mouse intestinal models rather than in people with gout. But it’s interesting because it suggests a second mechanism by which walnuts could influence uric acid beyond just being low in purines. If these peptides have similar effects in the human gut, walnuts might subtly limit how much purine precursor makes it into your bloodstream in the first place. Whether eating a realistic amount of walnuts produces enough of these peptides to matter is a question that hasn’t been answered yet.
Why Plant Purines Don’t Cause Gout the Way Meat Does
One of the most persistent misunderstandings about gout is that all purines are equally dangerous. They aren’t. A study tracking gout patients through recurrent attacks found that higher purine intake from animal sources increased the odds of a flare in a clear dose-response pattern, with those eating the most animal purines facing more than twice the risk compared to those eating the least. Purines from plant sources showed a much weaker and less consistent association with flares.8PubMed. Purine-rich foods intake and recurrent gout attacks
This finding has held up well across multiple studies and is reflected in modern dietary guidance for gout. The likely explanation involves differences in how the body processes purines depending on their food matrix. Animal-source purines come packaged with saturated fat, high protein loads, and other compounds that independently affect kidney function and uric acid handling. Plant-source purines arrive alongside fiber, antioxidants, and minerals that may buffer or counteract their purine contribution. Walnuts are a good example of this principle: they deliver almost no purines, but even if they delivered more, the overall package of healthy fats, polyphenols, and fiber would likely blunt any negative effect.
This matters for practical decisions. If you’ve been told to “avoid purines” and interpreted that as avoiding all plant foods with any purine content, you’re probably over-restricting your diet for minimal benefit. The evidence consistently shows that cutting back on red meat, organ meats, shellfish, and certain oily fish matters far more than worrying about the trace purines in nuts, legumes, or vegetables.
Where Walnuts Fit in a Gout-Friendly Eating Pattern
Gout management is increasingly understood as a whole-diet question, not a matter of policing individual foods. The DASH diet, originally designed for blood pressure control, has shown genuine promise for lowering uric acid. In a controlled trial, people assigned to the DASH pattern who started with elevated uric acid levels saw a reduction of about 1 mg/dL over 90 days. Among those who began the trial with levels at or above 6 mg/dL, three-quarters had dropped below that clinical target by the end of the study.9PubMed Central. DASH Diet and Change in Serum Uric Acid over Time
The DASH diet emphasizes fruits, vegetables, whole grains, lean protein, and nuts while limiting red meat, added sugars, and processed food. Walnuts slot naturally into this pattern as a snack, a salad topping, or a replacement for less gout-friendly protein sources. A comprehensive review of diet and gout management reinforced this whole-pattern approach, arguing that dietary modification for gout should focus on reducing metabolic syndrome risk factors, supplementing beneficial nutrients that affect uric acid metabolism and inflammation, and combining nutritional strategies with medication when needed.10PubMed Central. Gout and Diet: A Comprehensive Review of Mechanisms and Management
The practical takeaway is that you get more mileage from improving your overall eating pattern than from micro-managing individual foods. Walnuts are a useful part of that shift because they replace less favorable snack options, contribute anti-inflammatory compounds, and provide healthy fats without adding meaningful amounts of purines.
How Many Walnuts Are Reasonable
Most dietary guidelines suggest about 30 grams of nuts per day, which works out to roughly 14 walnut halves or a small palm-sized handful. At that serving size, you’re looking at under 6 mg of purines, well within any reasonable limit.1PubMed Central. Do Nuts Contain a Lot of Uric Acid, and Are Safe for a Low-Purine Diet? Even eating substantially more than that wouldn’t push your purine intake into concerning territory from walnuts alone.
The more realistic limit on walnut intake is calories. Walnuts are calorie-dense, around 185 calories per ounce, and excess weight is one of the strongest and most modifiable risk factors for gout. Gaining weight raises uric acid levels, and losing weight tends to lower them. So while walnuts are a nutritious choice, eating large quantities on top of an already calorie-heavy diet could work against you indirectly by contributing to weight gain. Keeping to a handful a day gives you the benefits without the caloric trade-off becoming an issue.
If you prefer other nuts, almonds and pine nuts are similarly low-purine options. Pine nuts showed even stronger evidence of reducing hyperuricemia risk in the observational study mentioned earlier.4PubMed Central. Nut intake and hyperuricemia risk in young adults Peanuts, while technically legumes, still fall in the low-purine range and are likely fine in moderation. There’s no strong evidence that any common nut or nut-like food triggers gout attacks.
What Walnuts Can and Cannot Do for an Active Flare
If you’re in the middle of a gout attack, eating walnuts won’t make it stop. Gout flares are driven by the immune system’s inflammatory response to urate crystals that have already deposited in your joint, and no food resolves that process quickly. Anti-inflammatory medications, colchicine, and corticosteroids are the tools for acute flares, and dietary changes are a long-game strategy for reducing the frequency and severity of future attacks.
That said, the anti-inflammatory properties of walnuts may contribute to a less reactive baseline over time. The oxidative stress reduction seen in post-walnut-meal studies, including that roughly 7% drop in a lipid oxidation marker, isn’t dramatic, but chronic low-grade inflammation is one of the factors that keeps gout patients cycling between attacks.3PubMed Central. Effect of a walnut meal on postprandial oxidative stress and antioxidants in healthy individuals Walnuts are rich in alpha-linolenic acid, a plant-based omega-3 fat that the body can partially convert into longer-chain omega-3s with anti-inflammatory properties. Incorporating them into your regular diet likely contributes to a less inflammatory internal environment, even if the effect from walnuts alone is modest.
Walnuts, Kidney Health, and Oxalates
People with gout have a higher-than-average risk of kidney stones, partly because uric acid itself can crystallize in the kidneys and partly because the metabolic conditions that produce gout also favor stone formation. Walnuts contain oxalates, compounds that can contribute to calcium oxalate kidney stones in susceptible people. This doesn’t mean walnuts are dangerous, but if you have a history of kidney stones alongside gout, it’s worth being aware of.
The amount of oxalate in a 30-gram serving of walnuts is moderate compared to high-oxalate foods like spinach or rhubarb. Staying well hydrated, keeping to reasonable serving sizes, and eating walnuts alongside calcium-containing foods (which binds oxalate in the gut before it reaches the kidneys) are simple strategies that largely neutralize the concern. For the vast majority of gout patients without a separate kidney stone history, walnut oxalates are not a practical worry.
What does connect to kidney health more directly is the emerging peptide research. The walnut-derived peptides that reduced uric acid production in intestinal tissue also reduced uric acid excretion, suggesting they may alter how much uric acid the gut passes along to the kidneys in the first place.7Food Bioscience. Walnut peptide reduce uric acid production by non-covalent binding to hypoxanthine in vitro If future research confirms this in humans, walnuts could turn out to be helpful for the kidney side of gout management as well, not just the joint side. For now, that remains a promising but unproven possibility.