Leeks are mild-flavored allium vegetables rich in prebiotic fiber and organosulfur compounds that support digestive and cardiovascular health. They provide essential micronutrients including vitamin K, folate, and potassium with minimal caloric density.
GutHeartInflammationBoneLiverLongevity
Nutrition per ~85 g · 1 leek
Form
52kcal
Protein1.3 g
Carbs12.0 g
Fat0.3 g
Fiber1.5 g
10.5 g net carbs after fiber.
Vitamins
Vitamin K39.9 mcg33%
Vitamin A1417 iu28%
Folate54.4 mcg14%
Vitamin B60.20 mg12%
Vitamin C10.2 mg11%
Vitamin A70.5 mcg8%
Vitamin E0.78 mg5%
Thiamin51 mcg4%
Pantothenic Acid0.12 mg2%
Niacin0.34 mg2%
Riboflavin25.5 mcg2%
Minerals & other
Manganese0.41 mg18%
Copper0.10 mg11%
Iron1.8 mg10%
Magnesium23.8 mg6%
Calcium50.1 mg4%
Potassium153 mg3%
Phosphorus29.8 mg2%
Selenium0.85 mcg2%
Choline8.1 mg1%
Zinc0.10 mg1%
Sodium17 mg1%
Monounsaturated Fat0.0034 g—
Polyunsaturated Fat0.14 g—
Saturated Fat0.034 g—
Bioactives estimated
Organosulfur (Allicin)~51 mg
Inulin / Prebiotic fibre~2.5 g
Glutathione~13 mg
Polyphenols~128 mg
Representative amounts for this food, not measured for this item. Real content varies widely by variety, ripeness and storage.
What drives the score weighted inputs
Nutrient density33.0/35Vitamins and minerals relative to calories — the single biggest driver.
Protein quality6.6/15How much protein it delivers, by absolute grams and per calorie.
Bioactives12.1/15Polyphenols, flavonoids and other beneficial plant compounds.
Fiber6.9/10Dietary fiber for gut health, satiety and steadier blood sugar.
Healthy fats5.0/10Fat quality — unsaturated against saturated, and trans-fat free.
Glycemic impact9.0/10Low sugar with a high fiber-to-carb ratio scores best.
These are the scored components, not a sum: the published score also reflects normalisation across the catalog, so the parts above will not add to 86.
MethylationAntioxidantATP / MitoBoneThyroidCollagenNeurotransmitterDetoxGlucoseHematopoiesisLipidsGut MicrobiomeMembranesClottingHPA AxisGlycolysisβ-OxidationKetogenesisNAD⁺mTORAMPKUrea CycleDopamineSerotoninSteroidogenesisVitamin D ActivationInsulin Signaling
Overview
Leeks (Allium ampeloprasum var. porrum) belong to the allium family alongside onions and garlic, originating in the Mediterranean region. They are distinguished by their mild, sweet flavor profile compared to sharper onion relatives. The white and light-green portions contain inulin, a soluble prebiotic fiber that feeds beneficial gut bacteria and supports metabolic health. Leeks are particularly rich in kaempferol and other flavonoids—polyphenolic compounds with demonstrated anti-inflammatory and antioxidant properties in human studies. The organosulfur compounds (including thiosulfides) released when leeks are chopped or cooked contribute to their cardiovascular and detoxification benefits. With 47 mcg of vitamin K per 100g, leeks support bone metabolism and vascular health. The prebiotic fiber content makes leeks especially valuable for longevity-focused nutrition: a healthy gut microbiome is now recognized as foundational for immune function, metabolic regulation, and even cognitive health. Leeks' low glycemic load (14.15g carbs with 1.8g fiber) makes them suitable for varied dietary approaches. Their nutrient density relative to caloric content, combined with emerging evidence linking allium vegetables to reduced cardiovascular mortality, positions leeks as an underrated staple for extended healthspan.
Health benefits 5
Prebiotic fiber support for gut microbiome diversity and short-chain fatty acid productionstrong
Inulin and fructooligosaccharides in leeks pass undigested to the colon, where beneficial bacteria ferment them into butyrate and other short-chain fatty acids that strengthen the intestinal barrier and reduce systemic inflammation
Cardiovascular protection through organosulfur compounds and potassiummoderate
Thiosulfides in leeks modulate platelet aggregation and endothelial function, while 180mg potassium per 100g supports healthy blood pressure regulation independent of sodium
Anti-inflammatory and antioxidant effects via kaempferol flavonoidsmoderate
Kaempferol suppresses NF-κB signaling pathways and reduces TNF-α production, lowering chronic systemic inflammation linked to aging and chronic disease
Bone health support through vitamin K-dependent protein activationmoderate
47 mcg of vitamin K per 100g activates osteocalcin and matrix Gla-protein, which direct calcium to bone matrix rather than soft tissue calcification
Detoxification support through enhanced Phase I and Phase II enzyme activityemerging
Organosulfur compounds upregulate glutathione S-transferase and other detoxification enzymes, improving clearance of xenobiotics and metabolic waste
Pairs with
Pair leeks with fermented foods (sauerkraut, kefir, tempeh) because the prebiotic inulin in leeks feeds the beneficial bacteria and enzymes already present in fermented foods, amplifying probiotic colonization
Combine leeks with leafy greens (spinach, kale) because both provide complementary fat-soluble vitamins (K, A); prepare together with olive oil to enhance absorption of these fat-soluble compounds
Pair leeks with turmeric and black pepper in soups or broths because curcumin's anti-inflammatory effects synergize with leek flavonoids, and piperine increases curcumin bioavailability
Combine leeks with sulfur-rich cruciferous vegetables (broccoli, cauliflower) because both activate detoxification pathways and provide complementary glucosinolates for Phase II enzyme support
In the kitchen
Store leeks upright in a jar with 1 inch of water in the refrigerator; they will keep for 2-3 weeks and continue to develop flavor complexity
Slice leeks lengthwise and rinse thoroughly between layers to remove soil and sand; white and light-green portions are tender enough for raw salads or light sautéing, while darker green tops are ideal for stocks and braises
Consume leeks with their skin on or in broths to maximize inulin and prebiotic fiber retention; cooking leeks slowly over low heat (rather than high-heat searing) preserves heat-sensitive organosulfur compounds
Prepare leek broth by simmering cleaned leek trimmed ends and green tops with water for 20-30 minutes to extract prebiotic fiber and minerals; refrigerate and use as a base for soups and grains
Pair leek consumption with adequate hydration; the prebiotic fiber requires sufficient water to support healthy fermentation in the colon and prevent digestive distress
When to eat it anytime
Leeks contain no stimulating compounds and their prebiotic benefits accrue throughout the day as fiber reaches the colon. They are equally beneficial at lunch or dinner. Morning consumption supports stable blood sugar and satiety; evening consumption is well-tolerated given low FODMAP content once properly cooked.
Breaks a fast
Leeks are not compatible with strict water fasting due to caloric and carbohydrate content (61 kcal, 14g carbs per 100g), but fit well within time-restricted feeding windows. Those with sensitive IBS or FODMAP intolerance should introduce leeks gradually and ensure thorough cooking to reduce oligosaccharide content.