Are Clams and Mussels Bad for Gout? Purines and Portions
Clams have about 135 mg of purines per 100 g. Mussels have no lab data in the USDA database and are likely higher. Portions, flares and better swaps.
TL;DR
- Clams have about 135 mg of purines per 100 g, in the high band. A 3-ounce (85 g) portion of clam meat is roughly 115 mg.
- Mussels have never been measured for the USDA purine database. Figures elsewhere, including ones Urica has used, run from about 170 to 310 mg per 100 g; we use 310 and treat mussels as very high until better data exist.
- Between flares, a modest portion of either is fine now and then. Skip both during a flare, and don’t pair a big pot of mussels with beer.
Clams and mussels aren’t off-limits with gout, but both belong in the “once in a while” group. Clams measure about 135 mg of purines per 100 g, and mussels are probably higher, although nobody has measured them for the USDA database.
That gap in the data matters, so this article is upfront about what’s measured and what isn’t.
How Many Purines Are in Clams and Mussels?
| Raw meat | Per 100 g | Per 3 oz (85 g) | Per 4 oz (113 g) | Band |
|---|---|---|---|---|
| Clams | ~135 mg | ~115 mg | ~153 mg | High |
| Mussels* | ~310 mg | ~264 mg | ~350 mg | Very high |
*Not in the USDA and ODS-NIH purine database. See the next section.
Our bands are: low (under 50 mg per 100 g), moderate (50–100), high (100–200) and very high (over 200). The clam figure is the median of three lab analyses in the USDA and ODS-NIH Database for the Purine Content of Foods (Release 2, 2025): a US sample from 1976, a Japanese one from 2014 and a Chinese one from 2017. They came in at about 136, 145 and 110 mg per 100 g. For purine data that’s a fairly tight spread, so the clam number is one you can lean on.
All figures are for raw meat, not shells. Cooking drives off water, so cooked meat reads higher per 100 g, but a given clam doesn’t gain purines in the pot.
Why Are the Mussel Numbers All Over the Place?
Mussels aren’t in the USDA database at all. The numbers we’ve seen in older tables and online run from roughly 170 to 310 mg per 100 g, and Urica’s own pages have used 172, 268 and 310 at different times. None of them trace to an analysis the database accepted. Its authors note that gout websites typically “do not give data on purine bases, nor do they cite their data sources.” Mussels are a good example.
We now use one figure everywhere: about 310 mg per 100 g, in the very high band. It’s the cautious choice. If mussels turn out to be lower, you’ve lost little by being careful. If they really are near the top, a lower figure would have misled you.
Either way, the practical point holds. Every mussel figure we’ve found is above the clam measurements, so mussels deserve at least as much care as clams, and probably more. At the low end of that range, a 3-ounce portion of mussel meat would be about 145 mg; at ours, about 264 mg.
How Do Clams and Mussels Compare With Other Shellfish?
| Shellfish (raw) | Purines per 100 g | Band |
|---|---|---|
| Mussels* | ~310 mg | Very high |
| Shrimp | ~180 mg | High |
| Squid | ~145 mg | High |
| Clams | ~135 mg | High |
| Oysters | ~120 mg | High |
| Crab | ~120 mg | High |
| Lobster | ~100 mg | High |
| Imitation crab* | ~25 mg | Low |
*Not in the USDA database; Urica’s reference value.
Clams sit in the middle of the pack, close to oysters and crab, and below shrimp. For a full list, see our purine content in seafood chart.
Why Shellfish Gets Extra Caution
The Arthritis Foundation says mussels, scallops, squid, shrimp, oysters, crab and lobsters “should only be eaten once in a while.” Clams aren’t named, but they measure in the same range.
Two findings support that advice:
- Short-term purine load. In a 2012 study of 633 people with gout, those in the highest fifth of purine intake over two days had about 4.8 times the odds of a recurrent attack compared with the lowest fifth. Purines from animal foods carried more risk than purines from plants.
- No omega-3 offset. A 2023 analysis of 12,505 US adults classed clams and mussels as omega-3-poor seafood. Each extra daily ounce of that group was linked to 8.7% higher odds of gout, while omega-3-rich fish showed no link. It was a cross-sectional survey, so it can’t prove cause.
How Much Clam or Mussel Is Reasonable?
- Clams: 3 to 4 ounces of meat, about 115–153 mg of purines, as an occasional main.
- Mussels: think starter, not main. Given the uncertainty, a small bowl shared at the table is a better fit than a big pot to yourself.
- Shells hide portions. A heaped bowl looks like a lot of food but is mostly shell, and it’s easy to keep going. Decide how many you’ll eat before the pot arrives.
- One shellfish per meal. Paella, cioppino, bouillabaisse and seafood pasta often stack clams, mussels and shrimp. Pick one.
- Go easy on the broth. Purines dissolve into cooking liquid, so mopping up a whole bowl of mussel broth adds to the total.
- Mind the drink. Moules-frites is often served with beer. The American College of Rheumatology’s 2020 guideline conditionally recommends limiting alcohol and purines for people with gout, whatever their disease activity. More in is beer bad for gout.
If you log meals, an app like Urica can estimate the purines in a seafood pasta or paella from a photo, which helps when several shellfish share one plate.
Clams and Mussels During a Flare vs. Between Flares
During a flare, skip clams, mussels and other shellfish until it settles. Start the treatment your doctor prescribed; the ACR guideline strongly recommends colchicine, NSAIDs or glucocorticoids as first-line options. The Arthritis Foundation suggests at least 8 glasses of nonalcoholic fluids a day, and 16 during a flare, with plain water as the best choice, unless you’ve been told to limit fluids. Our guide on how to stop a gout flare fast has the full checklist.
Between flares, a modest portion of clams now and then is reasonable for most people, as the only high-purine food of the meal. Keep mussels smaller and less frequent.
If you take a urate-lowering medicine, the ACR guideline strongly recommends keeping serum urate below 6 mg/dL, and it still suggests limiting purines alongside the medicine.
Chowder, Linguine and Other Clam and Mussel Dishes
- New England clam chowder: potatoes (about 5 mg per 100 g) and milk (close to zero) make up most of the bowl, so the clam amount is what counts. A cup is a moderate starter.
- Linguine with clams: pasta is low in purines. Load up on pasta and greens, and keep the clams to a normal portion.
- Moules-frites: fries are low in purines. The mussels are the load, so share the pot.
- Stuffed clams and clams casino: often topped with bacon, which is itself in the high band (about 100 mg per 100 g, 60–140 across analyses). Keep it to a couple.
- Canned clams: one 1976 analysis measured about 62 mg per 100 g. That’s a single sample, so treat canned clams like fresh until more data exist.
- Clam juice and seafood stock: not measured, but purines dissolve into cooking liquid, so use them as a flavoring, not a soup base you drink by the bowl.
Better Swaps for Clams and Mussels
| Instead of | Try | Why it helps |
|---|---|---|
| A big pot of mussels as a main | Clams, or mussels as a shared starter | Clams ~135 mg vs. up to ~310 mg per 100 g |
| Seafood pasta with clams, mussels and shrimp | Linguine with clams only, extra pasta and greens | One shellfish instead of three |
| Chowder in a bread bowl, then fried clams | A cup of chowder and a salad | Keeps the clam total modest |
| Shellfish salad | A salad made with imitation crab | ~25 mg per 100 g, though salty and lower in protein |
| Moules-frites with beer | The same meal with water or sparkling water | Cuts the alcohol |
The Bottom Line
Clams are a mid-range shellfish for gout: about 135 mg of purines per 100 g, backed by three lab analyses. A 3- to 4-ounce portion now and then is reasonable between flares. Mussels have no lab data in the USDA database, and the published figures suggest they’re higher, so we treat them as very high: keep them to a starter-sized portion, share the pot, and go easy on the broth and the beer. Skip both during a flare.
Sources
- USDA Agricultural Research Service. USDA and ODS-NIH Database for the Purine Content of Foods. Release 2, 2025.
- Arthritis Foundation. Gout Diet Dos and Don’ts.
- FitzGerald JD, et al. 2020 American College of Rheumatology Guideline for the Management of Gout. Arthritis Care & Research, 2020.
- Zhang Y, et al. Purine-rich foods intake and recurrent gout attacks. Annals of the Rheumatic Diseases, 2012.
- Zeng G, et al. n-3 PUFA poor seafood consumption is associated with higher risk of gout, whereas n-3 PUFA rich seafood is not: NHANES 2007–2016. Frontiers in Nutrition, 2023.
This article is for informational purposes only and is not medical advice. Talk to your rheumatologist or healthcare provider about your specific situation.
Track Your Personal Response
Everyone responds differently to foods. Urica helps you track how specific foods affect YOUR flare patterns by analyzing purines, fructose, and glycemic load together — not just purines alone.
Frequently Asked Questions
Are mussels worse than clams for gout?
Probably. Clams have been measured three times for the USDA and ODS-NIH purine database, at about 110 to 145 mg per 100 g. Mussels haven't been measured for it at all. The mussel figures we've found run from about 170 to 310 mg per 100 g, all above the clam results. If you're choosing between the two, clams are the safer bet.
Is clam chowder OK for gout?
A cup is usually fine between flares. Chowder is mostly potatoes, milk or cream and broth, all low in purines, with a modest amount of clam. The broth carries some purines too, because they dissolve into cooking liquid. Keep it to a cup rather than a bread bowl, and don't follow it with another shellfish course. Tomato-based Manhattan chowder works the same way.
Can I eat mussels during a gout flare?
It's best not to. Shellfish of any kind is worth skipping until a flare settles, and mussels are likely among the higher ones. Focus on the treatment your doctor prescribed, plenty of water, and low-purine meals built on eggs, dairy, grains and vegetables. Mussels can come back between flares as an occasional starter-sized portion.
Are canned clams lower in purines?
Possibly, but don't count on it. A single 1976 analysis found canned clams at about 62 mg per 100 g, roughly half the raw figure. But that's one sample from one decades-old study, not enough to call canned clams a low-purine food. Smoked clams and mussels haven't been analyzed at all. Treat canned and smoked shellfish like fresh: a modest portion, now and then.