Human Nutrition · Research Pitch
Your combo meal
is low key
salty as hell.
Same burger. Same fries. Three different kitchens: the drive thru, the freezer aisle, and your own stove. One of them is quietly loading your plate with way more sodium than the others.
nocapsodium.com
Nutrition Facts, America Edition
3,400mg
Avg. daily sodium,
U.S. adults
2,300mg
Recommended daily
limit (RDA)
That's 1,100 mg over the line, every single day, and it's not (just) the salt shaker.
Sources: FDA, "Sodium in Your Diet"; CDC, "About Sodium and Health"
Why 1,100 mg actually matters
Sodium is in practically all our foods. Although it tastes great, it is a ticking time bomb for our health. The CDC and FDA both point to excess sodium intake as a driver of hypertension. Hypertension is a leading risk factor for heart disease and stroke which are the top causes of death in the U.S. Most of that sodium doesn't come from the shaker on the table; it's already baked into the food before it reaches the plate.
That's the gap this project digs into. Not just how much sodium Americans eat, but where it's coming from and whether the answer changes depending on who cooked the food.
The Hypothesis
“Among U.S. adults, consuming restaurant-prepared sandwiches, hamburgers, fries, and pizza items will be associated with higher sodium intake compared to consuming store-bought versions of the same food categories and preparing food at home.”Full research question, sources & literature review →
The Receipts
See all 4 comparisons →Same food, three kitchens. Here's how the sodium stacks up when it's made at a chain, pulled from a package, or cooked from scratch.
Burger
2.0× more sodium, restaurant vs. homemade
Look closer: The patty is not what makes this salty. A BUBBA burger Original Beef patty carries 85 mg on its own, so almost the whole store bought total is the bun, the cheese slice and the ketchup around it.
Store BoughtBUBBA burger patty, bun, cheese slice and ketchup, assembled at home
712 mg
1 assembled burger
31% of a day's recommended sodium (2,300 mg)
Show the 4 parts that add up to 712 mg
Two of these four lines come from packaging that prints no gram weight. BUBBA lists the patty by the patty and Heinz lists ketchup by the serving, so both are quoted as the manufacturer states them rather than converted to grams.
HomemadeFresh ground beef patty, whole wheat roll, cheddar and mustard, cooked at home
525 mg
1 assembled burger
23% of a day's recommended sodium (2,300 mg)
Show the 4 parts that add up to 525 mg
The patty is USDA's own published portion: one patty yielded from a quarter pound of raw beef, which is 83 g once cooked. BUBBA prints no weight for its frozen patty, so the two are not matched by weight, and a heavier homemade patty would add sodium here. Nothing is salted during cooking, so every milligram below is what the ingredients already carry.
- 85% lean ground beef patty, pan broiled, no salt added (1 patty, 83 g cooked) [source]66 mg
- Whole wheat hamburger roll (1 roll, 56 g) [source]267 mg
- Cheddar cheese (1 slice, 21 g, matched to the Kraft slice) [source]137 mg
- Yellow mustard (1 tsp, 5 g) with fresh tomato and lettuce, which add under 10 mg [source]55 mg
- Total525 mg
Pizza
1.4× more sodium, store bought vs. homemade
Look closer: Pizza is the category where cooking it yourself barely helps. A from scratch slice still lands within about 45 mg of the same slice from a chain, because pizza dough is salted at around 2% of the flour weight and cheese and cured pepperoni are salty no matter who assembles them.
RestaurantDomino's Large Hand Tossed Pepperoni, 1 slice
640 mg
1 slice of a 14 inch pizza (about 116 g) [source]
28% of a day's recommended sodium (2,300 mg)
Show how this figure was worked out
Domino's publishes this pizza by the component rather than by the finished slice, so the figure is the sum of their own numbers for one slice: crust 170 mg, pizza sauce 90 mg, regular cheese 210 mg and pepperoni 170 mg. Their optional 25 mg garlic oil blend is left out, which is the choice that makes the restaurant number smaller rather than larger.
Store BoughtDiGiorno Rising Crust Pepperoni, frozen
830 mg
1/5 of a pizza (140 g) [source]
36% of a day's recommended sodium (2,300 mg)
HomemadeFrom scratch dough, unsalted tomato sauce, mozzarella and pepperoni
597 mg
1 slice, one eighth of a 14 inch pizza
26% of a day's recommended sodium (2,300 mg)
Show the 5 parts that add up to 597 mg
Built from one 14 inch pie divided into eight slices: 265 g of flour at 60% hydration, salted at 2% of flour weight, which is the standard range for pizza dough; 1 cup of unsalted tomato sauce; 2 cups of shredded mozzarella; and 6 pepperoni slices per slice of pizza. The flour and the sauce contribute almost nothing. The salt in the dough, the cheese and the cured pepperoni are the entire story.
- All purpose flour (265 g per pizza, so 33 g per slice) [source]1 mg
- Table salt kneaded into the dough at 2% of flour weight (5.3 g per pizza, so 0.66 g per slice) [source]256 mg
- Tomato sauce, no salt added (1 cup per pizza, so 31 g per slice) [source]3 mg
- Shredded low moisture part skim mozzarella (2 cups per pizza at 86 g per cup, so 21.5 g per slice) [source]147 mg
- Sliced pepperoni (6 slices, 12 g) [source]190 mg
- Total597 mg
The Study, at a Glance
Design
Observational, comparing self reported sodium intake across adults who typically eat restaurant, store bought, or homemade versions of the same food categories, rather than assigning people to a diet.
Measures
Dietary recall or food frequency survey data paired with nutrition label sodium values for the specific items reported, plus a tag for how the food was prepared: restaurant, store bought, or homemade.
Confounders to control
Overall diet quality, income, cooking frequency, age, and existing hypertension, all of which can independently shift both sodium intake and preparation method.
Why it's feasible
Nutrition data for named chains and packaged products is already public. The condition that is hardest to reach, true from scratch home cooking, is the one this project treats as the baseline.