Fish Sauce
Food · Pantry & Condiment · Food, Typed Supps
Saltier than seawater by a wide margin, and a genuine iodine source.
Stage by stage
- Umami (Taste receptors): A year of enzymatic breakdown leaves free amino acids that read as savoury depth.
- Salt concentration (Stomach): 8,255 mg sodium per 100 g — the salt is what kept it safe for that year.
- Sodium load (Circulation): A 5 g teaspoon carries around 400 mg, a fifth of the daily target.
- Iodine (Thyroid): 33 mcg per 100 g from the anchovies — small per serve, but unusual for a condiment.
Timing
Into the pan rather than onto the plate. Heat drives off the volatile amines that make it smell strong raw.
Time to effect
- 2–4 weeks: Blood pressure response to a change in sodium intake.
- Per teaspoon: Around 400 mg of sodium — the number worth carrying.
Allergens
Contains: Fish. May contain: Sulphites. Derived from what this food is, not from a product label.
Eating patterns
Fits: Pescatarian, Kosher, Keto, Low-FODMAP, Gluten-free. Depends on the product: Halal.
Satiety
Not scored: the satiety index is measured on 240 kcal servings, and nobody eats a 240 kcal serving of this. The question does not apply rather than the answer being unknown.
Environmental footprint
13.6 kg CO2e and 3691 litres of freshwater per kg, matched to "Fish (farmed)" in Poore & Nemecek (2018), Science 360.
Cost band
Mid — roughly £5 per kg, as a band midpoint rather than a price.
Key nutrients
Nutrition per 100g
- Calories: 51
- Protein: 6.8g
- Carbohydrate: 4.4g
- of which sugars: 4.4g
- Fat: 0.3g
- Fibre: 1.2g
- Sodium: 8255mg
Food vs. supplement
Fish sauce and soy sauce look interchangeable and are not: swapping one for the other by volume changes the sodium load by nearly half. Recipes that call for both are usually balancing them deliberately.
Kitchen tip
Measure it into a spoon rather than pouring from the bottle. It is nearly 50% saltier than soy sauce, and the pour habit usually carries over unchanged.
Common myth
“Fish sauce is basically soy sauce for seafood dishes.” In reality: They are not interchangeable. Fish sauce carries 8,255 mg of sodium per 100 g against soy sauce’s 5,600 — nearly 50% more — so swapping by volume quietly raises the salt in the dish by half. It is also an anchovy product, which is the detail that catches out vegetarians following Thai and Vietnamese recipes.
Recipes that use it
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