What a Restriction Filter Can and Cannot Decide
The finder sorts meals against twelve restriction tags — vegetarian, vegan,
gluten-free, dairy-free, nut-free, low-carb, keto, paleo, pescatarian, low-sodium,
Whole30 and low-FODMAP. A filter answers one question: does this recipe contain an
ingredient that breaks the tag? It cannot answer the harder question, which is whether
a particular package on your shelf is safe. That decision happens at the label, and the
label has its own rules.
The nine allergens U.S. law requires the label to name
Federal law names nine major food allergens. When a packaged food contains one of them,
or an ingredient that contains one, the label has to say so in plain language. The list
below is the FDA’s own, with the places each allergen most often hides in a meal
plan.
The nine major food allergens named by U.S. law (FDA).
| Allergen | What the label covers | Where it hides in a pairing plan |
| Milk | Milk and ingredients derived from it | Butter, ghee, cheese, cream, whey, casein, milk powder |
| Eggs | Egg white and yolk | Mayonnaise, egg wash, some dried pasta, baked goods |
| Fish | Fish such as bass, flounder and cod | Fish sauce, anchovy in Worcestershire sauce, Caesar dressing |
| Crustacean shellfish | Crab, lobster and shrimp | Shrimp paste, some stocks and bisques |
| Tree nuts | Almonds, walnuts, pecans and other tree nuts | Almond flour, cashew cream, nut butters, praline |
| Peanuts | Peanuts, listed separately from tree nuts | Satay, some chilli sauces, peanut oil, baked goods |
| Wheat | Wheat and any ingredient that contains it | Soy sauce, breadcrumbs, some stocks and spice blends |
| Soybeans | Soybeans and soy-derived ingredients | Tofu, tempeh, edamame, soy sauce, some marinades |
| Sesame | Sesame seed and sesame-derived ingredients | Tahini, hummus, sesame oil, some breads and crackers |
Sesame is the newest entry. The FASTER Act named it the ninth major allergen, and the
labeling rules applied to sesame from 1 January 2023. The FDA also notes that products
already on retail shelves before that date did not have to be relabelled, so older
stock can still be missing the declaration. One practical consequence for this tool:
peanuts are a legume and the FDA lists them separately from tree nuts, so a
“nut-free” tag covers both classes here but the label is what settles it.
“Gluten-free” is a defined claim, not a style of eating
For celiac disease the phrase on the box has a legal meaning. The FDA set the limit at
less than 20 parts per million for the unavoidable presence of gluten, and a food may
carry the claim only if it contains no wheat, rye, barley or crossbreed ingredient, no
derivative of those grains that has not been processed to remove gluten, and no
derivative that still leaves 20 ppm or more. Gluten itself is a mixture of proteins
that occur naturally in wheat, rye and barley. That matters when you pick a side dish:
a rice pilaf is not automatically gluten-free if the stock or the soy sauce in it brings
wheat back in. Use the
substitution
finder for the swap, then read the label on the replacement.
Where restricted eating patterns run short
A restriction removes foods, and removal is where nutrient gaps start. The amounts below
are the published recommended daily intakes for adults from the NIH Office of Dietary
Supplements, with the reason each one matters for a plant-based or allergen-avoiding
pattern.
Recommended daily intakes for adults and why a restricted pattern changes them (NIH ODS).
| Nutrient | Published daily amount | Who that number is for | Why the pattern changes it |
| Vitamin B12 | 2.4 mcg | Adults | Plant foods contain no B12 unless they are fortified |
| Iron | 8 mg for men 19–50; 18 mg for women 19–50 | Adults by sex | Vegetarians need almost twice as much because nonheme iron is absorbed less well |
| Calcium | 1,000 mg at 19–50; 1,200 mg for women 51–70 and everyone 71 and older | Adults by age and sex | A dairy-free plate has to reach it through fortified drinks, tofu or greens such as kale and bok choi |
| Zinc | 11 mg for men; 8 mg for women | Adults | Beans, nuts and whole grains carry zinc, so legume and nut exclusions remove sources |
The finder is a starting point for the meal, not a nutrition audit. Once you have three
meals that clear your tags, run the
nutrition
calculator over the day to see whether the totals land near those figures, use the
macro
calculator when protein and fat split matter, and keep the
meal prep
planner for the week so a restriction does not turn into a single repeated dish.
Sources:
U.S. Food and Drug Administration, “Food Allergies”;
FDA, “‘Gluten-Free’ Means What It Says”;
NIH Office of Dietary Supplements, Vitamin B12;
Iron;
Calcium;
Zinc.