Asparagus

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By the Nutriveda editorial team · Updated 5 November 2026

Asparagus (Asparagus officinalis) is a spring vegetable: the young shoots of a perennial plant, sold green, white or purple. 100 g of raw asparagus has only 20 kcal, 2.1 g of fibre, 52 µg of folate and 42 µg of vitamin K. Four boiled spears give about 89 µg of folate, around a fifth of the daily value, which makes asparagus a good vegetable source of this B vitamin. It also contains natural prebiotic fibres, and it is known for one side effect: the smell it gives to urine, which more than half of people in a large study could not detect.

Asparagus nutrition per 100 g and per portion

Nutrient	Raw, 100 g	Boiled, 100 g	Portion: 4 boiled spears (60 g)
Energy	20 kcal	22 kcal	13 kcal
Protein	2.2 g	2.4 g	1.4 g
Fat	0.1 g	0.2 g	0.1 g
Carbohydrate	3.9 g	4.1 g	2.5 g
of which sugars	1.9 g	1.3 g	0.8 g
Fibre	2.1 g	2.0 g	1.2 g
Folate	52 µg	149 µg	89 µg
Vitamin K	41.6 µg	50.6 µg	30.4 µg
Vitamin A (RAE)	38 µg	50 µg	30 µg
Beta-carotene	449 µg	604 µg	362 µg
Vitamin E	1.1 mg	1.5 mg	0.9 mg
Vitamin C	5.6 mg	7.7 mg	4.6 mg
Thiamin (B1)	0.14 mg	0.16 mg	0.10 mg
Potassium	202 mg	224 mg	134 mg
Iron	2.1 mg	0.9 mg	0.5 mg
Copper	0.19 mg	0.17 mg	0.10 mg

Source: USDA FoodData Central, SR Legacy: “Asparagus, raw” (FDC 168389) and “Asparagus, cooked, boiled, drained” (FDC 168390), checked 5 November 2026. The portion column is calculated from the boiled record’s measure “4 spears (1/2″ base)” = 60 g. Values rounded.

The raw and boiled figures are two separate USDA records, so they do not line up neatly: the boiled record shows almost three times more folate and less than half the iron of the raw one. Cooking does not create folate, so read this as variation between the analysed samples, not as an effect of boiling. NIH uses the boiled value in its folate table: 4 boiled spears, 89 µg, 22% of the Daily Value. Even the lower raw figure, 52 µg per 100 g, is 26% of the EU reference intake for folate (200 µg), and 41.6 µg of vitamin K is 55% of the EU reference intake (75 µg), both above the 15% level for a “source of” claim (Regulation 1169/2011, Annex XIII).

Glycemic index

Asparagus is not listed in the international GI tables (Atkinson 2008), so we do not give a number for it. With 3.9 g of carbohydrate per 100 g raw, 2.1 g of which is fibre, a normal portion adds very little digestible carbohydrate to a meal. For how GI works, see What is the glycemic index.

Health benefits: what the evidence says

• Folate. NIH sets the adult RDA at 400 µg DFE a day and 600 µg in pregnancy. For foods that are at least a source of folate, which asparagus is, the EU allows claims such as “folate contributes to maternal tissue growth during pregnancy” and “folate has a role in the process of cell division” (Regulation 432/2012). One thing food cannot replace: NIH advises women who could become pregnant to take 400 µg of folic acid a day from supplements, fortified foods or both, on top of the folate they get from food.
• Vitamin K. NIH explains that vitamin K is needed to make proteins for blood clotting and bone metabolism, and sets the adequate intake at 120 µg a day for men and 90 µg for women. Four boiled spears give about 30 µg, a third of a woman’s adequate intake. That is a moderate amount, far below leafy greens like kale.
• Natural prebiotic fibres. The International Scientific Association for Probiotics and Prebiotics (ISAPP) lists asparagus with leek and chicory among foods with naturally occurring prebiotics. ISAPP also notes that you would need to eat large amounts of such foods for a prebiotic effect, so see asparagus as one part of a fibre-rich diet. More in our prebiotic foods list.
• Few calories, real fibre. At 20 kcal per 100 g, raw asparagus meets the EU “low energy” threshold (no more than 40 kcal per 100 g). Its 2.1 g of fibre per 20 kcal is well above the “source of fibre” level of 1.5 g per 100 kcal (Regulation 1924/2006). EFSA considers 25 g of fibre a day adequate for normal bowel function in adults.

How to eat asparagus

• Prepare: bend each spear near the bottom and it snaps where the woody part starts, or cut off the last 2-3 cm. Thin green asparagus needs no peeling. White asparagus has a fibrous skin: peel the whole stem from just below the tip downwards.
• Steamed or boiled: 3-5 minutes for medium spears, until a knife goes in with little resistance. Dress with lemon and olive oil.
• Roasted or grilled: toss with a little olive oil and salt and roast at about 200-220 °C for 10-15 minutes, or grill until lightly charred. Finish with grated Parmesan.
• With eggs: spears dipped into a soft-boiled egg, asparagus with a poached egg, or cut into an omelette or frittata with eggs and herbs.
• Raw: shave young spears into thin ribbons with a vegetable peeler and dress them like a salad.
• Soups, risotto and pasta: cut into short pieces and add in the last few minutes; simmer the trimmed ends in water for a light stock.
• Buying and storage: choose firm, straight spears with tight, closed tips. Stand them upright in a glass with a little water in the fridge, or wrap the ends in a damp towel, and cook within 2-3 days.

Who should be careful

• Warfarin (Coumadin). NIH warns that sudden changes in vitamin K intake can increase or decrease the effect of warfarin. Asparagus has a moderate amount, about 30 µg in four boiled spears, but in spring some people eat it every day in large portions. Keep your vitamin K intake steady and talk to your doctor before big changes.
• IBS and the low-FODMAP diet. In the FODMAP guide by the Monash University team (Yao, Biesiekierski, Shepherd and Gibson, published by IFFGD), asparagus is listed among high-FODMAP vegetables. If you follow a low-FODMAP plan, test small portions, ideally with a dietitian.

Traditional view (Ayurveda)

In Usha and Vasant Lad’s food guidelines asparagus is favourable for all three doshas: Vata, Pitta and Kapha. This is a traditional view, not a clinical finding.

Related entries and articles

• Broccoli and green beans – other green vegetables that cook in minutes
• Artichokes and leeks – other vegetables with natural prebiotic fibres
• Eggs – the classic partner for asparagus
• Kale – much richer in vitamin K, worth knowing if you take warfarin
• Prebiotic foods list: what they are and where to find them
• Plant-based meals for weight loss

FAQ

Why does asparagus make your urine smell?

Your body breaks down compounds in asparagus into metabolites that give urine a strong, typical odour. Not everyone notices it: in a BMJ study of 6,909 US adults, 58% of men and 61.5% of women could not smell it, and this was linked to genetic variation near several smell receptor genes.

Is asparagus good to eat in pregnancy?

Yes, it is a useful food: four boiled spears give about 89 µg of folate (NIH), and the RDA in pregnancy is 600 µg DFE a day. Food alone is not the recommendation, though: NIH advises women who could become pregnant to take 400 µg of folic acid a day from supplements, fortified foods or both. Ask your doctor or midwife which supplement fits you.

Can you eat asparagus raw?

Yes. Young, thin spears are tender raw: shave them into ribbons and dress them with lemon and olive oil. Raw asparagus has 20 kcal and 52 µg of folate per 100 g (USDA).

Sources

1. USDA FoodData Central, SR Legacy: Asparagus, raw (FDC 168389). fdc.nal.usda.gov
2. USDA FoodData Central, SR Legacy: Asparagus, cooked, boiled, drained (FDC 168390). fdc.nal.usda.gov
3. NIH Office of Dietary Supplements: Folate, Fact Sheet for Health Professionals. ods.od.nih.gov
4. NIH Office of Dietary Supplements: Vitamin K, Fact Sheet for Health Professionals. ods.od.nih.gov
5. Commission Regulation (EU) No 432/2012, Annex (authorised health claims). legislation.gov.uk
6. Regulation (EC) No 1924/2006 on nutrition and health claims made on foods, Annex (nutrition claims and conditions). legislation.gov.uk
7. Regulation (EU) No 1169/2011, Annex XIII (reference intakes). legislation.gov.uk
8. International Scientific Association for Probiotics and Prebiotics (ISAPP). Prebiotics: A Consumer Guide for Making Smart Choices. isappscience.org
9. Markt SC, Nuttall E, Turman C, et al. Sniffing out significant “Pee values”: genome wide association study of asparagus anosmia. BMJ 2016;355:i6071. Europe PMC
10. Yao CK, Biesiekierski J, Shepherd S, Gibson P. What Are FODMAPs? With a Menu Guide. International Foundation for Gastrointestinal Disorders (IFFGD). iffgd.org
11. EFSA NDA Panel (2010). Scientific Opinion on Dietary Reference Values for carbohydrates and dietary fibre. EFSA Journal 8(3):1462. efsa.europa.eu
12. Atkinson FS, Foster-Powell K, Brand-Miller JC. International Tables of Glycemic Index and Glycemic Load Values: 2008. Diabetes Care 2008;31(12):2281-2283. PMC
13. Lad U, Lad V. Food Guidelines for Basic Constitutional Types, from Ayurvedic Cooking for Self-Healing, 2nd ed. The Ayurvedic Institute. ayurveda.com

This page is for information only and is not medical or dietary advice.