Espresso

Food · Drink · Food, Typed Supps

Reads as the most caffeinated coffee there is. Per cup, it usually isn’t.

Stage by stage

Concentration (Mouth): Roughly four times as concentrated as filter coffee, in roughly a quarter of the volume.
Absorption (Stomach & small intestine): Caffeine absorption is essentially complete, with almost none lost.
Adenosine block (Brain): Peak effect at 30–60 minutes; half the dose is still circulating five hours later.
Clearance (Liver (CYP1A2)): Smoking speeds clearance; pregnancy and oral contraceptives slow it markedly.

Timing

The five-hour half-life is the number that matters: a 4 pm double shot leaves roughly half its caffeine circulating at 9 pm. Food slows absorption slightly but does not change the total dose.

Time to effect

30–60 min: Peak plasma caffeine and peak alertness.
4–6 hrs: Half the dose remains — longer in pregnancy or on oral contraceptives.

Allergens

None of the fourteen major allergens. Derived from what this food is, not from a product label.

Eating patterns

Fits: Vegan, Vegetarian, Pescatarian, Halal, Kosher, Gluten-free. Depends on the product: Keto, Low-FODMAP.

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

28.5 kg CO2e and 1571 litres of freshwater per kg, matched to "Coffee" in Poore & Nemecek (2018), Science 360.

Cost band

Pricey — roughly £20 per kg, as a band midpoint rather than a price.

Key nutrients

Nutrition per 100g

Calories: 10
Protein: 1.7g
Fat: 0.3g
of which saturated: 0.1g
Sodium: 2mg

Food vs. supplement

Caffeine tablets and espresso are pharmacologically the same molecule, but the tablet arrives without the ritual, the volume, or the natural ceiling that having to drink another cup imposes. Overdose case reports cluster around powders and tablets, not around coffee.

Kitchen tip

If you are counting caffeine, count shots and not cups — a large flat white and a small one differ by a whole shot, while the milk volume between them changes nothing that matters.

Common myth

“Espresso has more caffeine than any other coffee.” In reality: Per millilitre, easily. Per cup, usually not. A double shot delivers around 170 mg; a 250 mL mug of filter coffee lands in much the same range, and a large takeaway filter coffee beats it outright. The confusion comes from reading a concentration figure as though it were a dose.