Lime

Food · Fruit · Food, Typed Supps

A lime won't make your body "alkaline" or flush out toxins — but it is a real, small source of vitamin C.

Stage by stage

Squeeze & Taste (Mouth): Lime's citric acid and aromatic oils activate sour-taste receptors on the tongue, stimulating saliva and setting digestion in motion.
Acid-Stable Transit (Stomach): In the stomach's acidic environment, lime's ascorbic acid stays chemically stable rather than breaking down.
Vitamin C Uptake (Small intestine): The small intestine absorbs vitamin C via active sodium-dependent transporters, along with citrus flavonoids like hesperidin and naringin.
Collagen & Defense (Connective tissue): Absorbed vitamin C acts as a cofactor for building collagen in skin, blood vessels, and bone, and as an antioxidant that helps neutralize free radicals.

Timing

Lime's vitamin C absorbs well with or without food, but its acidity (pH roughly 2.0-2.4) can erode tooth enamel with frequent isolated sipping, so it's better paired with a meal or followed by a water rinse.

Time to effect

Days to weeks: Ascorbic acid from lime raises plasma vitamin C levels within hours, but the benefits tied to vitamin C status — wound healing, collagen synthesis, antioxidant capacity — reflect intake patterns sustained over days to weeks rather than a single serving.

Allergens

None of the fourteen major allergens. Derived from what this food is, not from a product label.

Eating patterns

Fits: Vegan, Vegetarian, Pescatarian, Halal, Kosher, Keto, Low-FODMAP, Gluten-free.

In season

September to December in the northern hemisphere, March to June in the southern.

Satiety

The satiety index is measured on 240 kcal servings. At 28 kcal per 100 g that is 857 g of this, which is not a serving anyone eats — so the index has nothing to say about it.

Environmental footprint

0.4 kg CO2e and 83 litres of freshwater per kg, matched to "Citrus fruit" in Poore & Nemecek (2018), Science 360.

Cost band

Cheap — roughly £3 per kg, as a band midpoint rather than a price.

Key nutrients

Vitamin C
Citric acid
Flavonoids (hesperidin, naringin)
Potassium
Fiber (in pith and peel)

Nutrition per 100g

Calories: 28
Protein: 0.8g
Carbohydrate: 1.2g
of which sugars: 1.2g
Fat: 0.1g
of which saturated: 0g
Fibre: 3.6g
Sodium: 2mg

Food vs. supplement

One lime provides about 20 mg of vitamin C — a real but modest contribution toward the roughly 75-90 mg daily target — plus fiber and citrus flavonoids that isolated 500-1000 mg supplement doses don't include.

Kitchen tip

Roll the lime under your palm before cutting to release more juice, zest it before juicing to capture the aromatic peel oils, and add lime juice near the end of cooking since its vitamin C degrades with prolonged heat.

Common myth

"Drinking lime water first thing in the morning alkalizes your body and flushes out toxins." In reality: Blood pH is tightly regulated by the lungs and kidneys within a narrow range (about 7.35-7.45) regardless of diet; lime juice itself is acidic (pH roughly 2.0-2.4), and there is no clinical evidence that citrus water changes body pH or removes "toxins" beyond what the liver and kidneys already handle. A separate, well-documented risk is real, though: lime juice on skin followed by sun exposure can cause phytophotodermatitis ("margarita burn"), a chemical burn from the peel's furanocoumarins reacting with UV light.