One Number the Label Never Prints, Calculated for Forty Cans
Credit: Daily Vitality
You are standing in front of forty red-and-white cans, and every one of them is telling you something. Hearty. Chunky. Rich. Reduced sodium. Twenty-four grams of protein. The front of the label is a sales pitch, and the back of the label is an accounting document, and the two are not always describing the same product.
Here is the thing about soup: nobody buys it for one nutrient. You buy it because it is eleven o'clock at night, or because it is the only thing in the cupboard, or because it is cold and you want something warm that takes ninety seconds. Soup is a convenience purchase, and convenience purchases are the ones we never audit.
So we audited them. Not on sodium alone, which tells you very little by itself, and not on protein alone, which tells you almost as little. We divided one by the other. The result is a single number — milligrams of sodium per gram of protein — that answers the question you were actually asking when you picked the can up: what am I getting for the salt?
That number is not printed on any can in America. It is not on the panel, not on the shelf tag, not in the marketing copy. We built it from the manufacturers' own filed labels, for forty cans spanning the aisle, and what came back was a 215-fold spread between the best row and the worst.
What follows is the countdown, from the can that gives you the most protein per milligram of sodium all the way down to number one, which gives you the least. The numbers behind every row are printed alongside it, so you can check our arithmetic against the can in your hand.
Every figure in this piece traces back to one place: the Branded Foods release of USDA FoodData Central, dated April 30, 2026. That database holds the Nutrition Facts panels that manufacturers themselves have filed, which means we are not estimating anything. We are reading the label, at scale.
The raw file is large enough to be unwieldy — twenty-six million nutrient rows — so the first job was narrowing. Filtering to the database's own canned-soup categories returned 15,083 branded records. Of those, 1,866 carried no usable sodium-and-protein panel and were set aside. Another 4,922 were broths, stocks, bouillons and consommés, which we excluded on purpose: a product with essentially no protein sends the ratio toward infinity and tells you nothing at all. A further 5,649 had no net weight we could read with confidence. That left 2,646 complete records to draw the final forty from.
One more screen matters, and it is worth understanding. Protein is rounded to the nearest whole gram on a Nutrition Facts panel. A can declaring one gram could really hold anywhere from half a gram to a gram and a half, which means its ratio carries roughly fifty percent uncertainty in either direction. We required at least two grams of declared protein per labeled serving, which removed 315 more records. Without that floor, the worst places on this list would have gone to rounding noise rather than to measured differences — several store-brand cream soups threw off index values between 650 and 860 that rested entirely on a single rounded digit.
We also dropped two records outright for contradicting themselves. One national store brand filed the same cream of mushroom twice in 2023 with protein differing two-fold between filings, and one organic lentil record appeared to carry its no-salt-added sibling's panel. Both are exactly what a stale or mis-filed record looks like, and neither belongs in a ranking.
If you have ever felt that the numbers on a soup can seem small for something you eat in one sitting, you were reading the label correctly. The reason sits in a table of federal reference amounts.
The Food and Drug Administration sets a reference amount customarily consumed for every food category, and for soups that amount is 245 grams — roughly one cup. It appears in the table at 21 CFR 101.12, where the label statement is given as "___ cup (___ g); ___ cup (___ mL)". That 245 grams is not a recommendation about how much soup to eat. It is a measuring stick, drawn from national food consumption surveys, and every container rule in the aisle is computed against it.
Once you know the number, the arithmetic of the aisle opens up. A standard 15-ounce ready-to-serve can is 425 grams, or 174 percent of the reference amount. A 19-ounce can is 538 grams, or 220 percent. Those percentages are not trivia — they decide how the can is allowed to be labeled.
Two provisions do the work here, and both are worth knowing before you read another soup label.
The first is the single-serving rule. A product packaged and sold individually that contains less than 200 percent of its reference amount "must be considered to be a single-serving container, and the entire content of the product must be labeled as one serving," in the words of 21 CFR 101.9. For soup, 200 percent of 245 grams is 490 grams. That means a 15-ounce can is a one-serving container by rule, full stop.
The second is the dual-column rule. Containers holding between 200 and 300 percent of the reference amount — 490 to 735 grams for soup — must print a second column showing the whole package alongside the per-serving one. The 18.5- and 19-ounce cans that most hearty lines use land squarely in that band, which is why those cans already show you the per-can number.
Here is what we found when we checked our forty against those thresholds. Twenty-seven of the forty cans are under 490 grams, making them single-serving containers by rule. Thirteen sit in the dual-column band. Among the ready-to-serve cans specifically, fifteen are under 490 grams — and eight of those still carried a multi-serving declaration on their filed record, usually somewhere between 1.7 and 1.9 servings.
FoodData Central holds the label a manufacturer filed at the time of filing, not necessarily the label on the shelf this week. Records in this index carry dates between 2017 and 2023, and package sizes have moved in that window — several brands have shifted between 18.5, 18.6 and 19-ounce cans. Treat a mismatch between a row here and a can in your hand as a prompt to run the arithmetic yourself, not as an error in either.
Condensed soup looks like the thing that should break a ranking like this one. You are comparing a can of concentrate against a can of finished soup, and those are not the same object.
Start with how condensed cans are labeled, because this is commonly misunderstood. The panel on a condensed can is declared as packaged, not as prepared. Campbell's condensed chicken noodle, for example, declares its serving as "1/2 cup condensed soup (120g)" and prints its figures against that condensed half-cup — a detail confirmed by the FoodData Central record for that product. Some cans also print an as-prepared column, which federal labeling rules allow, requiring that equal prominence be given to both sets of values.
And then the problem dissolves, for a reason that is almost too simple. The can of water a condensed soup asks you to add contains no sodium and no protein. Adding it changes both the volume and the concentration, but it cannot change the ratio between two things that are not in the water. A condensed can scores identically whether you measure it condensed or measure it prepared.
The same algebra carries further. Because sodium per can and protein per can are both the per-100-gram figure multiplied by the same net weight, that net weight cancels out of the division entirely. No rank on this list depends on how we read a package weight. We still print sodium per can and protein per can in every row, because those are the numbers that let you audit us — but the ranking itself rests on the ratio alone, which is the most stable thing on the label.
Screenshot that table and you have the whole aisle in your pocket. The narrative for each row follows.
Two milligrams of sodium per gram of protein. Nothing else in the field comes within a factor of six of it, and the reason is not subtle: the can holds 34 milligrams of sodium and 15.9 grams of protein. The published panel for the 15-ounce can, listed by Whole Foods Market, gives 20 milligrams of sodium and 9 grams of protein per cup.
What makes this row interesting is not the salt that was left out. It is that the can still carries more protein than most of the hearty, meat-forward cans further down this list. Lentils did that, not the seasoning decision.
At 14 milligrams per gram, this is the second-lowest row, built on 55 milligrams of sodium across the whole 425-gram can. Protein is modest at 4 grams, which is what chicken-and-rice formulations tend to deliver.
That modest protein is why it scores behind its lentil sibling despite both being low-sodium products. The ratio rewards the denominator, and rice is not a protein.
This is where the list gets useful, because nothing about this can is unusual. It is a normal supermarket soup, seasoned normally, and it scores 39 — the best ratio of any conventionally salted can we measured. The math is 799 milligrams of sodium against 20.4 grams of protein in a 425-gram can.
Split peas and ham are both dense in protein, and the can is compact. Those two facts together are the entire explanation.
At 41 milligrams per gram, this row sits a whisker behind the split pea. It is also one of the cleaner labels in the set: the 425-gram can declares itself a single serving, which matches what the federal threshold requires of a container that size.
There is no translation to do here. What the panel says is what the can holds — 408 milligrams of sodium, 10 grams of protein.
Sixty milligrams per gram, and the best-scoring mainstream national-brand can on the list. It carries 1,447 milligrams of sodium — genuinely a lot — and 24.2 grams of protein, the most protein of any can in the index.
Progresso is unusual in saying so out loud. The product page for this soup advertises "24g of protein per can," which is the number this index needs and the number almost nobody else prints. Our computed figure came back at 24.2 grams, which is about as close as label rounding permits.
This row is the clearest demonstration of what the index measures. A high-sodium can can still rank near the top, because the question is not how much salt is in there — it is what the salt is buying.
Sixty-one milligrams per gram, from 1,433 milligrams of sodium and 23.6 grams of protein in a 445-gram can. That is the second-highest protein load in the whole field, and it comes from a line priced well above the standard condensed shelf.
The premium bought real chicken here, and the ratio registers it.
At 68, this is one of the few cans that is moderate on sodium and solid on protein at the same time: 1,001 milligrams and 14.6 grams across 524 grams of soup.
Most cans on this list are good at one of those two things. Being unremarkable at both, in the right direction, turns out to be an effective strategy.
Seventy-six milligrams per gram. The 425-gram can declares itself a single serving, so the panel figures and the per-can figures are the same thing — 1,293 milligrams of sodium and 17 grams of protein.
If you have ever wanted a soup label that requires no arithmetic at all, this is what one looks like.
Seventy-seven milligrams per gram, from 1,470 milligrams of sodium and 19 grams of protein. Like the Cento, this 19-ounce can declares the whole container as its serving.
Put it beside the Healthy Choice split pea at 39 and you can see the pattern and its limit in one comparison. Both are split pea, both are protein-dense, and the gap between them is almost entirely a seasoning decision.
For a broader look at which foods deliver protein most efficiently, our ranking of the best protein per dollar across 25 foods runs the same style of arithmetic on the grocery budget.
At 78, this store-brand reduced-sodium chicken noodle outperforms several national hearty lines. The can holds 1,012 milligrams of sodium and 12.9 grams of protein across 527 grams.
Reduced-sodium claims are hit and miss on this index, as you will see further down. This one landed, because the formulation had protein to divide by in the first place.
Ninety-seven milligrams per gram, from 1,514 milligrams of sodium and 15.6 grams of protein in a 539-gram can. Hold onto this number — it becomes the reference point for the condensed chicken noodles near the bottom of the list.
A 19-ounce can sits in the dual-column band, so this is one of the labels that already prints the whole-can figures for you.
The same trade-off between convenience and what you get for the sodium shows up outside the soup aisle — we ran it on batch-cooked chicken against deli meat using cost, protein and sodium together.
Ninety-eight milligrams per gram, essentially tied with the Progresso. The 456-gram can carries 1,470 milligrams of sodium and 14.9 grams of protein.
The comparison that matters is not against Progresso. It is against Campbell's own condensed chicken noodle, which scores 297 — three times worse. Same brand, same flavor concept, three-fold difference in what the salt buys you.
Also 98, from 1,604 milligrams of sodium and 16.3 grams of protein in a 498-gram can. This is Target's hearty line, and on this measure it is indistinguishable from the national brands it sits next to.
Store brand does not predict position on this list in either direction, which is worth remembering when you reach number one.
We found something similar when we asked which grocery stores offer the best nutrition per dollar — the banner on the door explains less than people expect.
At 103, with 720 milligrams of sodium and 7 grams of protein in a 400-gram can that declares itself one serving. It is the lowest-sodium can in this stretch of the list by a wide margin.
The protein is where it gives ground. Seven grams is respectable for a vegetarian can and modest against the meat-based soups scoring similarly.
One hundred and six milligrams per gram, which sounds unremarkable until you notice it is a cream-based chowder. Every other chowder here scores worse, and most score much worse. The can holds 918 milligrams of sodium and 8.7 grams of protein.
Clams carry protein. Cream and potato do not. Chowders live or die on which of those three ingredients the brand was generous with.
One hundred and thirteen, from 1,488 milligrams of sodium and 13.2 grams of protein in a 462-gram can. That is a solid protein load paired with a sodium figure that is solidly high.
At 462 grams the can is under the 490-gram threshold, making it a single-serving container by rule — though its filed record still declares about 1.9 servings.
One hundred and twenty. At 854 milligrams of sodium in a 425-gram can, this is among the least salty rows in the middle of the table, but 7.1 grams of protein is not much to divide into.
It is a clean illustration of why sodium alone is a poor guide: two cans with very different salt loads can land within a few points of each other here.
One hundred and twenty-three, from 1,584 milligrams of sodium and 12.8 grams of protein. The protein is genuinely good for a cream-based soup; the sodium is what moves the number. This is the first row where the creamy formulations begin their long slide toward the bottom of the list.
One hundred and thirty-six. Same 524-gram can and a similar sodium figure at 1,458 milligrams, but protein falls to 10.7 grams.
Potato-forward soups consistently place lower than their meat content suggests, because the potato adds weight and flavor without adding much to the bottom of the fraction.
One hundred and forty-five, from 1,640 milligrams of sodium and 11.3 grams of protein in a 462-gram can. Among the Chunky soups we measured, this is the least efficient.
Steak in the name, potato in the can. The ratio notices the difference.
One hundred and fifty-two — against 106 for the Bar Harbor chowder measured on the same basis. Both are New England-style clam chowders; one is 43 percent worse per gram of protein than the other. The can carries 1,663 milligrams of sodium and 10.9 grams of protein.
Within-category spread like this is the strongest argument for reading the panel rather than the category name.
One hundred and sixty. This matters more than its position suggests, because it is one half of the cleanest paired comparison in the whole index.
Target's standard condensed chicken noodle prints 920 milligrams of sodium and 2 grams of protein per half-cup. This reduced-sodium version, from the same brand and the same shelf, prints 480 milligrams and 3 grams. Sodium nearly halves and protein goes up. The ratio improves by a factor of 2.9 — from 459 to 160.
That is what a reduced-sodium line looks like when it is a genuine reformulation rather than a smaller number in a smaller portion.
One hundred and seventy-two, from 688 milligrams of sodium and 4 grams of protein in a 400-gram single-serving can.
The sodium here is among the lowest in the bottom half of the table. Four grams of protein is simply not enough to carry it.
One hundred and seventy-three, essentially tied with the Amy's despite holding more than twice the sodium — 1,517 milligrams against 688. The difference is 8.8 grams of protein against 4.
Two very different cans arriving at the same number is a good reminder that this index is a ratio, not a scoreboard for either ingredient on its own.
One hundred and seventy-eight. The 298-gram condensed can holds 2,155 milligrams of sodium and 12.1 grams of protein — a serious protein figure that still cannot rescue the ratio.
From here down, condensed cans increasingly dominate the list, and that is not a coincidence.
Also 178, from 1,935 milligrams of sodium and 10.9 grams of protein in a 533-gram can. Against the Bar Harbor chowder at 106, that is a 68 percent difference between two products with nearly identical names.
If you take one shelf-level lesson from this index, let it be that "New England clam chowder" describes a flavor, not a formulation.
One hundred and eighty-five, from 738 milligrams of sodium and 4 grams of protein across a 408-gram can that declares itself a single serving.
Quinoa, kale and red lentil is a list of ingredients people associate with protein density. At 4 grams in the whole can, the association does not survive contact with the panel.
Two hundred and five. At 1,019 milligrams of sodium, this is by some distance the least salty condensed can in the index. It also holds only 5 grams of protein.
Cutting the sodium roughly in half against its condensed neighbors moved it up the table without changing what kind of soup it is.
Two hundred and eight, from 1,040 milligrams of sodium and 5 grams of protein in a 539-gram can that declares the whole container as its serving.
Put this beside the Market Pantry pair at number 19 and you have the honest answer to whether reduced-sodium lines improve this index: sometimes substantially, sometimes barely. A tomato-and-cream base has very little protein to divide by, so cutting the salt moves the number but cannot move it far.
Working to a specific sodium figure is a different exercise from this ratio, and one we handle separately in our guide to staying under 1,500 mg a day while still eating normal food.
Two hundred and thirteen, from 2,190 milligrams of sodium and 10.3 grams of protein in a 340-gram condensed can. The protein is good — better than most condensed cans manage.
The sodium is the highest per gram of any can this size in the index. Neither the organic certification nor the premium price predicted this position.
Two hundred and seventeen, from 1,613 milligrams of sodium and 7.4 grams of protein in a 298-gram condensed can.
The pasta shapes are the product. Nutritionally it is a standard condensed chicken soup, and it scores like one.
Two hundred and twenty-three on the ratio, and a distinction of its own: at 2,316 milligrams in a 425-gram can, this carries more sodium than any other can we measured. Because it is condensed, that figure describes the contents before the water goes in.
Worst ratio and most sodium are different questions with different answers, and this row is where they separate. Number one on this list does not hold the most sodium. This one does.
If tracking where sodium accumulates across a whole grocery cart interests you, we have also mapped 12 sneaky sources of sodium that tend to go unexamined.
Two hundred and thirty-nine, from 1,189 milligrams of sodium and 5 grams of protein in a 305-gram condensed can.
Cheese is a protein-dense food. Broccoli cheese soup, on this evidence, contains the idea of cheese rather than a useful quantity of it.
Two hundred and forty, from 1,220 milligrams of sodium and 5.1 grams of protein in a 305-gram condensed can. On sodium alone it is one of the more restrained condensed soups on the shelf.
Tomato soup was never a protein food and has never claimed to be. The index simply prices that honestly: you are buying tomato, and the salt that makes tomato taste like soup.
Two hundred and ninety, from 2,158 milligrams of sodium and 7.4 grams of protein in a 298-gram can.
It sits within a few points of the standard condensed chicken noodle below it, which tells you the cream did not meaningfully change the accounting in either direction.
Two hundred and ninety-seven. The 10.75-ounce can holds 2,261 milligrams of sodium and 7.6 grams of protein, working out to 890 milligrams and 3 grams per declared half-cup of condensed soup.
Now put it beside Campbell's Chunky Classic Chicken Noodle at 98, and Progresso's ready-to-serve chicken noodle at 97. Three cans, one flavor, and the condensed version is three times less efficient than either ready-to-serve competitor. That single comparison is the best summary of the condensed pattern this index found.
Three hundred and thirty-five, and an unusual row: at 669 milligrams, it holds less sodium than almost anything else down here. It also holds 2 grams of protein in the entire 391-gram can.
One caution belongs on this row. Two grams is right at our rounding floor, so the true ratio could plausibly sit anywhere from roughly 270 to 450. The position is sound; the precision is not.
Three hundred and sixty-eight, from 1,584 milligrams of sodium and 4.3 grams of protein in a 524-gram can.
Nearly all of this end of the table is condensed. This one is not, which makes it the outlier worth knowing about — a full-size ready-to-serve can carrying condensed-level inefficiency.
Four hundred and twenty-nine milligrams of sodium per gram of protein. The panel reads 860 milligrams of sodium and 2 grams of protein per half-cup of condensed soup, as the filed record shows, which comes to 2,137 milligrams and 5 grams across the 298-gram can.
There is a fair defense of this row, and it is worth stating. Most cream of mushroom is bought as an ingredient — a binder for a casserole, not a bowl of lunch. But it goes into the dish whole, and when it does, it brings this ratio with it.
Here is where the countdown ends. Target's store-brand condensed chicken noodle prints 920 milligrams of sodium and 2 grams of protein against a half-cup serving, confirmed against the filed panel. Across the 298-gram can that is 2,227 milligrams of sodium and 4.9 grams of protein.
What makes this the last row is not the salt. Campbell's condensed chicken noodle prints 890 milligrams against the same half-cup — a difference of thirty milligrams, which is nothing. The gap is entirely on the other side of the fraction. Campbell's declares 3 grams of protein where this declares 2, and that single gram, one third of the total, moves the index 54 percent.
That is the finding this whole index was built to surface. The salt in the soup aisle is broadly similar from can to can. What varies enormously — by a factor of 215 from the top of this list to the bottom — is what you get in exchange for it.
Three patterns held across the whole field, and each one survives brand changes and reformulations in a way that a list of product names does not.
Condensed cans score worse, consistently. The condensed median is 231 milligrams of sodium per gram of protein against 104 for ready-to-serve. Because the index is unaffected by dilution, that gap is real and not an artifact of comparing a concentrate against a finished soup — condensed formulations are simply built on more starch, cream and broth and less meat or legume.
Legumes dominate the good end. Six of the eight best rows are lentil or split pea soups, which arrive with 15 to 24 grams of protein per can before the brand makes a single seasoning decision. Cream, cheese and chowder formulations occupy seven of the worst twelve, across organic and conventional lines and across price tiers alike.
And the hearty lines earn their premium. Campbell's Chunky Classic Chicken Noodle at 98 against Campbell's condensed chicken noodle at 297, and Progresso's chicken noodle at 97 against the same 297, are threefold improvements delivered by more meat rather than less salt.
The same logic we used here applies in other aisles too — our ranking of canned fish on omega-3s per dollar and mercury per serving takes a similar per-unit approach to a shelf where the label leaves the useful number out.
About the Author
Angela Nightingale is a Senior Editor at Daily Vitality with over two decades of experience in digital publishing and health and wellness content. She specializes in turning complex, often-confusing health topics into clear, calm, and practical guidance that respects the reader's intelligence. Her work focuses on helping people feel informed and confident — never overwhelmed or alarmed — as they make everyday decisions about how they eat, move, rest, and age.
It is the sodium in the can, in milligrams, divided by the protein in the can, in grams. A soup scoring 100 delivers 100 milligrams of sodium for every gram of protein it gives you. It is a purchasing ratio — a way of asking what the salt in a can is buying — not a measure of how much sodium is in a serving and not a statement about the food's overall quality.
Because sodium alone answers the wrong question. Two cans in this index — one at 854 milligrams of sodium and one at 1,584 — land within a few points of each other on the ratio, because the second carries nearly twice the protein. Ranking on sodium alone would have put those cans in completely different places and told you nothing about what you get for the difference.
No, and this is the reason condensed and ready-to-serve cans can appear on one list. The water a condensed can calls for contains neither sodium nor protein, so it changes the volume and the concentration but not the ratio between them. A condensed can scores identically whether measured as packaged or as prepared.
The panel is declared as packaged. A condensed can's serving is typically stated as half a cup of the condensed product, and the figures printed beside it describe that concentrate, not the finished bowl. Some cans add a second as-prepared column, which labeling rules permit provided both sets of values get equal prominence.
They have essentially no protein, which sends the ratio toward infinity and produces a meaningless number. We excluded 4,922 broth, stock, bouillon and consommé records for that reason. The index is designed for soups you eat as food, not liquids you cook with.
By federal rule, a can holding less than 200 percent of the 245-gram reference amount — that is, under 490 grams — is a single-serving container, and the whole can must be labeled as one serving. A standard 15-ounce can is 425 grams, so it qualifies. Twenty-seven of the forty cans in this index are under that threshold.
Two reasons. Condensed cans legitimately declare more than one serving, because the reference amount applies to the prepared soup and every condensed can here prepares to well over 490 grams. Among ready-to-serve cans, eight of the fifteen under-490-gram cans in our field still carried a multi-serving declaration on their filed record — and a filed record can predate the label currently on the shelf.
Bumble Bee New England Condensed Clam Chowder, at 2,316 milligrams in a 425-gram can. It is not number one on the ratio, which sits at 223. Most sodium and worst ratio are genuinely different questions.
Progresso Mediterranean-Style Lentil, at 24.2 grams per 19-ounce can, narrowly ahead of Campbell's Slow Kettle Southwest-Style Chicken at 23.6 grams. Progresso is also the only brand in the field that advertises the per-can protein figure rather than the per-serving one.
Both happen, and we found one of each. Target's reduced-sodium condensed noodle soup cuts sodium from 920 to 480 milligrams per serving while raising protein from 2 grams to 3, improving the ratio by a factor of 2.9. Progresso's reduced-sodium creamy tomato improves too, but only to 208, because a tomato-and-cream base has very little protein to divide by.
Not systematically. A store brand takes the number one position, but store brands also appear at 78, 98 and 173, mixed in among the national labels throughout the table. Brand tier did not predict position in either direction.
They come from the FoodData Central Branded Foods release dated April 30, 2026, which holds labels as manufacturers filed them. Individual records in this index carry filing dates between 2017 and 2023, and formulations and can sizes do change. We validated four anchor products against currently published panels and all four reproduced our figures to within label rounding.
