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Coffee

Coffea arabica / Coffea canephora

Also known as coffee, brewed coffee, filter coffee, espresso

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The brewed infusion of roasted, ground Coffea seeds, and the largest single source of polyphenols in many national diets simply because of how much of it is drunk. The USDA entry is for coffee brewed with tap water and does not include milk or sugar.

Energy & MetabolismLiver HealthHeart HealthMuscle & Physical Performance

Potential health benefits

Best supported: Strong

Ordered by how well the human research supports them — strongest first. A rating describes the state of the evidence, not how impressive the food is. How we rate evidence.

Alertness and energy

Energy & Metabolism
Strong evidence

Caffeine effects on alertness, reaction time and perceived fatigue are among the best-replicated findings in nutrition, demonstrated across many randomised trials. Two caveats: tolerance develops within days, and in habitual drinkers much of the morning lift is the wearing off of overnight withdrawal rather than performance above an unexposed baseline.

What may be going on: Caffeine blocks adenosine receptors, opposing the accumulation of sleep pressure signalling during waking hours.

Strong evidence. Consistent findings across multiple good-quality human studies.

3 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Liver markers

Liver Health
Strong evidence

Cohort studies and meta-analyses consistently link regular coffee drinking with lower liver enzyme levels, less hepatic fibrosis and lower rates of chronic liver disease, with a dose-response pattern that holds across very different populations. The data are observational so residual confounding cannot be excluded, but the consistency is unusual for a food, and the association appears for decaffeinated coffee too, which points away from caffeine as the explanation.

Strong evidence. Consistent findings across multiple good-quality human studies.

2 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Blood lipid profile

Heart Health
Moderate evidence

Trials and meta-analyses show that unfiltered coffee raises LDL cholesterol, an effect attributed to the diterpenes cafestol and kahweol, while paper-filtered coffee does not. This is a claim in the unhelpful direction, and it is one of the clearest brewing-method effects in the food literature.

Moderate evidence. Several human studies point the same way, with real caveats.

4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Cardiovascular risk markers

Heart Health
Moderate evidence

Large cohort meta-analyses find moderate coffee intake associated with slightly lower all-cause and cardiovascular mortality, in a U-shaped pattern where very high intakes lose the association. This is observational, and people who tolerate coffee well differ systematically from those who avoid it.

Moderate evidence. Several human studies point the same way, with real caveats.

4 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Exercise performance

Muscle & Physical Performance
Moderate evidence

Meta-analyses report small but consistent improvements in endurance performance and, to a lesser degree, strength outcomes with caffeine taken about an hour before exercise. Doses studied are typically 3–6 mg per kilogram of body weight, responses vary between individuals, and habitual intake blunts the effect somewhat.

Moderate evidence. Several human studies point the same way, with real caveats.

2 sources

Deep research mode adds each paper’s own conclusion and stated limitations.

Ask about Coffee

Ask about Coffee

Answers are written only from the entries on this page — the same nutrients, compounds, claims and citations you can read above. Nothing is added from outside the database, and every answer lists what it was built from.

AI explanations are not switched on for this site, so there is nothing to ask here. Everything above is read straight from the database and does not need them.

Key nutrients

Nutrient content per 100 grams
NutrientAmount% DV
Macronutrients
Calories1 kcal0%
Protein0.12 g0%
Total fat0.02 g0%
Carbohydrate0 g0%
Fibre0 g0%
Total sugars0 g—
Water99.4 g—
Fats
Saturated fat0.0020 g0%
Monounsaturated fat0.015 g—
Polyunsaturated fat0.0010 g—
Cholesterol0 mg0%
ALA (omega-3)0 g—
EPA (omega-3)0 g—
DHA (omega-3)0 g—
DPA (omega-3)0 g—
Linoleic acid (omega-6)0.0010 g—
Vitamins
Vitamin A0 µg0%
Vitamin C0 mg0%
Vitamin D0 µg0%
Vitamin E0.01 mg0%
Vitamin K0.1 µg0%
Thiamin (B1)0.014 mg1%
Riboflavin (B2)0.076 mg6%
Niacin (B3)0.191 mg1%
Pantothenic acid (B5)0.254 mg5%
Vitamin B60.0010 mg0%
Folate2 µg1%
Vitamin B120 µg0%
Choline2.6 mg0%
Minerals
Calcium2 mg0%
Iron0.01 mg0%
Magnesium3 mg1%
Phosphorus3 mg0%
Potassium49 mg1%
Sodium2 mg0%
Zinc0.02 mg0%
Copper0.0020 mg0%
Manganese0.023 mg1%
Selenium0 µg0%
Other measured compounds
Beta-carotene0 µg—
Alpha-carotene0 µg—
Lycopene0 µg—
Lutein + zeaxanthin0 µg—
Caffeine40 mg—
Ash0.35 g—

Nutrient values are per 100 g of the USDA reference entry named on this page and vary with variety, growing conditions, storage and preparation.

Source record: Beverages, coffee, brewed, prepared with tap water (USDA FoodData Central, FDC ID 171890).

% DV uses the FDA Daily Values for adults and children aged 4 and over. A dash means no Daily Value has been established for that nutrient.

Bioactive compounds

Compounds present in meaningful amounts. Presence is banded rather than quantified, because whole-food levels vary enormously with variety, growing conditions, storage and preparation.

How preparation changes things

Only effects with real support are listed. If a preparation method is missing, it is because nothing dependable is documented — not because it makes no difference.

  • brewedReduces cafestol and kahweol (LDL-raising diterpenes)

    A paper filter retains most of the coffee diterpenes, which is why filtered coffee behaves differently from French press and boiled coffee in lipid trials. Metal mesh filters retain far less.

  • roastedReduces chlorogenic acid

    Roasting degrades a substantial share of the chlorogenic acids in green coffee beans, so darker roasts carry less. Caffeine, by contrast, is relatively heat-stable and changes little with roast level.

Things to know

Allergies, interactions and intake concerns. Every food gets this section — a reference where everything is uniformly good is not a reference.

  • Too much

    Caffeine: sleep, anxiety and palpitations

    Caffeine has a half-life of several hours, so afternoon coffee measurably degrades sleep quality even in people who fall asleep fine. High intakes cause anxiety, tremor and palpitations, and around 400 mg a day is the ceiling most food authorities cite for healthy adults. Stopping abruptly produces headache and fatigue for a few days.

  • Worth knowing

    Pregnancy caffeine limits

    Caffeine clearance slows substantially during pregnancy, and most authorities advise capping total caffeine at around 200 mg a day — roughly two modest cups of brewed coffee, less than some coffee-shop servings contain in one cup.

  • Interaction

    Large swings in caffeine clearance from other drugs

    Caffeine is metabolised by CYP1A2. Fluvoxamine, ciprofloxacin and oral contraceptives slow its clearance markedly, so a normal number of cups can behave like a much larger dose; smoking speeds clearance, so quitting effectively raises caffeine exposure overnight.

  • Worth knowing

    Unfiltered brewing raises LDL cholesterol

    Cafestol and kahweol, diterpenes present in coffee oils, raise LDL cholesterol. Paper filters retain them; French press, boiled and Scandinavian-style coffee do not, and espresso sits in between. Anyone managing cholesterol who drinks a lot of unfiltered coffee has an easy lever available.