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Asparagus

Asparagus officinalis

Also known as Sparrow grass, Green asparagus, White asparagus

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The young shoots of a perennial lily relative, harvested in spring. White asparagus is the same plant grown covered so the spears never develop chlorophyll.

Gut & Digestive HealthKidney & Urinary Health

Potential health benefits

Best supported: Limited

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.

Gut microbiome

Gut & Digestive Health
Limited evidence

Research suggests the inulin-type fructans in asparagus act as substrate for colonic bacteria, consistent with the broader prebiotic fibre literature. Trials using asparagus itself are few.

Limited evidence. Early human work, or mostly lab and animal research.

4 sources

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

Bowel regularity

Gut & Digestive Health
Insufficient evidence

Asparagus contributes both fermentable and insoluble fibre, and fibre intake as a category has reasonable support for stool frequency. There is essentially no research on asparagus specifically.

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.

Kidney and urinary function

Kidney & Urinary Health
Insufficient evidence

Asparagus has a long reputation as a kidney-cleansing and diuretic food. There is no dependable human research showing it changes kidney function or urinary outcomes, and the healthy kidney does not require dietary assistance to filter blood.

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

1 source

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

Ask about Asparagus

Ask about Asparagus

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
Calories20 kcal1%
Protein2.2 g4%
Total fat0.12 g0%
Carbohydrate3.88 g1%
Fibre2.1 g8%
Total sugars1.88 g—
Water93.2 g—
Fats
Saturated fat0.04 g0%
Monounsaturated fat0 g—
Polyunsaturated fat0.05 g—
Cholesterol0 mg0%
EPA (omega-3)0 g—
DHA (omega-3)0 g—
DPA (omega-3)0 g—
Linoleic acid (omega-6)0.04 g—
Vitamins
Vitamin A38 µg4%
Vitamin C5.6 mg6%
Vitamin D0 µg0%
Vitamin E1.13 mg8%
Vitamin K41.6 µg35%
Thiamin (B1)0.143 mg12%
Riboflavin (B2)0.141 mg11%
Niacin (B3)0.978 mg6%
Pantothenic acid (B5)0.274 mg5%
Vitamin B60.091 mg5%
Folate52 µg13%
Vitamin B120 µg0%
Choline16 mg3%
Minerals
Calcium24 mg2%
Iron2.14 mg12%
Magnesium14 mg3%
Phosphorus52 mg4%
Potassium202 mg4%
Sodium2 mg0%
Zinc0.54 mg5%
Copper0.189 mg21%
Manganese0.158 mg7%
Selenium2.3 µg4%
Other measured compounds
Beta-carotene449 µg—
Alpha-carotene9 µg—
Lycopene0 µg—
Lutein + zeaxanthin710 µg—
Caffeine0 mg—
Ash0.58 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: Asparagus, raw (USDA FoodData Central, FDC ID 168389).

% 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.

  • steamedPreserves folate and vitamin C

    Asparagus is a good folate source, and folate is both water-soluble and heat-sensitive. Steaming or brief roasting retains considerably more of it than boiling.

  • boiledReduces folate and fructans

    Boiling leaches folate into the water, though it also removes some of the fructans that cause digestive symptoms in sensitive people.

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

    High FODMAP content

    Asparagus is high in fructans and excess fructose and is commonly restricted on a low-FODMAP plan for irritable bowel syndrome, where even a few spears can provoke symptoms.

  • Worth knowing

    Odorous urine

    Asparagusic acid is broken down into volatile sulphur compounds that give urine a distinctive smell within half an hour. Whether you notice it depends on genetic variation in both production and the ability to detect it, and it is entirely harmless.

  • Worth knowing

    The purine question

    Asparagus appears on older gout avoidance lists because of its purine content. Large cohort studies found no increase in gout risk from purine-rich vegetables, so that restriction is generally no longer recommended.

  • Allergy

    Contact dermatitis in handlers

    Asparagus is a documented cause of occupational contact dermatitis and, less commonly, of food allergy, most often in growers and kitchen workers handling raw spears.