Capers

Capparis spinosa

What capers has been studied for

2 associations assessed — none with dependable human evidence behind them yet. Strongest first.

2 Insufficient

Healthy blood pressureHeart Health · no source yetInsufficient— jump to the detail and sources
Oxidative stress markersAntioxidant & Oxidative Stress · no source yetInsufficient— jump to the detail and sources

2 things to know first — allergies, interactions and intake limits

About capers

The unopened flower buds of a Mediterranean shrub, cured in brine, vinegar or dry salt — they are inedibly bitter fresh. The USDA entry is for the canned product, so most of what it describes is the curing medium as much as the bud.

Also known as capers, caper buds, nonpareille capers, câpres

Heart Health Antioxidant & Oxidative Stress

The evidence in depth

Best supported: Insufficient

What each association actually rests on, and the papers behind it. A rating describes the state of the research, not how impressive the food is. How we rate evidence.

Healthy blood pressure

Heart Health

Insufficient evidence

Capers are frequently cited as a top dietary source of quercetin, and quercetin supplement trials at around 500 mg a day report small blood pressure reductions. The arithmetic does not carry across: the tablespoon someone eats supplies a tiny fraction of that, and comes with a large amount of sodium that pushes the other way.

Insufficient evidence. Not enough human research to say anything useful yet.

No source is attached to this association yet, so it is rated insufficient by default. It is listed because people commonly ask about it — not because there is evidence for it.

Oxidative stress markers

Antioxidant & Oxidative Stress

Insufficient evidence

Caper extracts do well in laboratory antioxidant assays, as concentrated flavonoid sources tend to. Human trials measuring oxidative stress markers after eating capers do not exist.

Insufficient evidence. Not enough human research to say anything useful yet.

No source is attached to this association yet, so it is rated insufficient by default. It is listed because people commonly ask about it — not because there is evidence for it.

Ask about Capers

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
Nutrient	Amount	% DV
Macronutrients
Calories	23 kcal	1%
Protein	2.36 g	5%
Total fat	0.86 g	1%
Carbohydrate	4.89 g	2%
Fibre	3.2 g	11%
Total sugars	0.41 g	—
Water	83.8 g	—
Fats
Saturated fat	0.233 g	1%
Monounsaturated fat	0.063 g	—
Polyunsaturated fat	0.304 g	—
Cholesterol	0 mg	0%
EPA (omega-3)	0 g	—
DHA (omega-3)	0 g	—
DPA (omega-3)	0.0010 g	—
Linoleic acid (omega-6)	0.111 g	—
Vitamins
Vitamin A	7 µg	1%
Vitamin C	4.3 mg	5%
Vitamin D	0 µg	0%
Vitamin E	0.88 mg	6%
Vitamin K	24.6 µg	21%
Thiamin (B1)	0.018 mg	2%
Riboflavin (B2)	0.139 mg	11%
Niacin (B3)	0.652 mg	4%
Pantothenic acid (B5)	0.027 mg	1%
Vitamin B6	0.023 mg	1%
Folate	23 µg	6%
Vitamin B12	0 µg	0%
Choline	6.5 mg	1%
Minerals
Calcium	40 mg	3%
Iron	1.67 mg	9%
Magnesium	33 mg	8%
Phosphorus	10 mg	1%
Potassium	40 mg	1%
Sodium	2348 mg	102%
Zinc	0.32 mg	3%
Copper	0.374 mg	42%
Manganese	0.078 mg	3%
Selenium	1.2 µg	2%
Other measured compounds
Beta-carotene	83 µg	—
Alpha-carotene	0 µg	—
Lycopene	0 µg	—
Lutein + zeaxanthin	0 µg	—
Caffeine	0 mg	—
Ash	8.04 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: Capers, canned (USDA FoodData Central, FDC ID 172238).

% 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.

soakedReduces sodium content
Rinsing brined capers under running water, or soaking salt-packed ones for several changes of water, removes a substantial part of the surface salt without much affecting flavour.

Things to know

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

Worth knowing
Very high sodium as sold
Brined and salt-packed capers are among the saltiest things in a normal kitchen, and a tablespoon contributes a noticeable share of a day’s sodium. Anyone managing blood pressure or fluid retention should count them, and salt-packed capers need soaking rather than a quick rinse.
Worth knowing
Pickled foods and histamine sensitivity
Vinegar-cured foods are commonly listed as triggers by people who react to histamine or to fermented and pickled products, though the evidence base for histamine intolerance itself is thin.