Nutrition per ~140 g · 2–3 lemons
41kcal
Protein1.5 g
Carbs13.0 g
Fat0.4 g
Fiber3.9 g
9.1 g net carbs after fiber.
Vitamins
Vitamin C74.2 mg82%
Vitamin B60.11 mg7%
Pantothenic Acid0.27 mg5%
Thiamin56.0 mcg5%
Folate15.4 mcg4%
Riboflavin28.0 mcg2%
Vitamin E0.21 mg1%
Niacin0.14 mg1%
Vitamin A30.8 iu1%
Vitamin A1.4 mcg0%
Minerals & other
Copper51.8 mcg6%
Iron0.84 mg5%
Potassium193 mg4%
Calcium36.4 mg3%
Magnesium11.2 mg3%
Manganese42.0 mcg2%
Phosphorus22.4 mg2%
Choline7.1 mg1%
Selenium0.56 mcg1%
Zinc84.0 mcg1%
Sodium2.8 mg0%
Saturated Fat0.055 g—
Monounsaturated Fat0.015 g—
Polyunsaturated Fat0.12 g—
Bioactives estimated
Polyphenols~210 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 density32.8/35Vitamins and minerals relative to calories — the single biggest driver.
Protein quality8.4/15How much protein it delivers, by absolute grams and per calorie.
Bioactives13.1/15Polyphenols, flavonoids and other beneficial plant compounds.
Fiber10.0/10Dietary fiber for gut health, satiety and steadier blood sugar.
Healthy fats5.0/10Fat quality — unsaturated against saturated, and trans-fat free.
Glycemic impact10.0/10Low 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 95.
What it feeds primary sources only
Systems
ImmuneBrainSleepCardioGutEnergyMuscleBonesHormonesSkinStressLiverKidneyEyesReproductiveJoints
Pathways
MethylationAntioxidantATP / MitoBoneThyroidCollagenNeurotransmitterDetoxGlucoseHematopoiesisLipidsGut MicrobiomeMembranesClottingHPA AxisGlycolysisβ-OxidationKetogenesisNAD⁺mTORAMPKUrea CycleDopamineSerotoninSteroidogenesisVitamin D ActivationInsulin Signaling
Overview
Native to South Asia, lemons have been cultivated for over 2,500 years and are now a staple in Mediterranean and global cuisines. Despite their sour taste, lemons are alkalinizing post-digestion and deliver exceptional nutrient density relative to caloric content. The primary longevity-relevant compounds are vitamin C (53mg per 100g—over half the daily value), flavonoid polyphenols (particularly hesperidin and diosmin), and citric acid. Lemon's low glycemic impact (9g carbs, mostly fiber) makes it compatible with various dietary approaches. The peel contains significantly higher polyphenol concentrations than the flesh, including d-limonene, a compound studied for metabolic and immune support. Lemons' high vitamin C content supports collagen synthesis, immune function, and iron absorption, while their polyphenols exhibit anti-inflammatory properties associated with reduced chronic disease risk. The citric acid may enhance calcium solubility and support kidney health through citrate metabolism.
Health benefits 5
Enhanced iron absorption from plant-based sourcesstrong
Vitamin C reduces ferric iron to ferrous form, significantly increasing non-heme iron bioavailability from plant foods
Antioxidant and anti-inflammatory supportstrong
Flavonoids (hesperidin, diosmin) and vitamin C neutralize reactive oxygen species and modulate inflammatory pathways
Collagen synthesis and connective tissue healthstrong
Vitamin C is an essential cofactor for prolyl and lysyl hydroxylases, enzymes required for collagen cross-linking and stability
Kidney stone risk reductionmoderate
Citric acid increases urinary citrate, which inhibits calcium oxalate crystallization
Metabolic and weight management supportemerging
D-limonene in peel and polyphenols may enhance fat oxidation and improve insulin sensitivity
Pairs with
- Pair with spinach or kale because vitamin C dramatically increases absorption of non-heme iron in leafy greens (up to 3-fold enhancement)
- Combine with fatty fish or olive oil because fat-soluble polyphenols and fat-soluble vitamin absorption may be enhanced together
- Mix with legumes (beans, lentils) because lemon's citric acid and vitamin C increase mineral bioavailability from plant-based proteins
- Add to turmeric because citrus polyphenols may enhance curcumin absorption and anti-inflammatory synergy
In the kitchen
- Use lemon zest in meals to access concentrated polyphenol content (2-3x higher in peel than flesh); wash thoroughly first to remove pesticides
- Consume fresh lemon juice immediately after squeezing to preserve vitamin C, which degrades rapidly upon exposure to air and light
- Add lemon juice to cooked vegetables or legumes to enhance mineral absorption post-meal rather than relying solely on supplement timing
- Store whole lemons at room temperature for up to 2 weeks, or refrigerate in airtight containers for up to 4 weeks to slow vitamin degradation
When to eat it anytime
Lemon's low caloric density and lack of glycemic impact make it suitable throughout the day. Consuming with meals maximizes iron and mineral absorption benefits.
Fasting-compatible
Lemon water during fasting is popular, though the citric acid may increase gastric acid production in sensitive individuals. Time lemon with plant-based meals to optimize iron bioavailability.