Jalapeño
Food · Vegetable · Food, Typed Supps
A jalapeño's fire is a trick your nerves fall for, not an injury — and it definitely won't give you an ulcer.
Stage by stage
- Burn signal (Mouth & nerves): Capsaicin binds to TRPV1 receptors on sensory nerves in the mouth, triggering the same pain pathway as physical heat, without any actual tissue damage.
- Passes through (Stomach): Contrary to popular belief, capsaicin does not erode the stomach lining; evidence suggests it can increase protective mucus and blood flow instead.
- Nutrient absorption (Small intestine): Vitamin C, vitamin B6, and other water-soluble nutrients are absorbed across the small intestine while capsaicin is absorbed more slowly and metabolized.
- Circulation & effect (Bloodstream): Absorbed capsaicin circulates and can transiently raise energy expenditure and catecholamine levels before being metabolized and cleared.
Timing
Eating jalapeños alongside a meal, especially one with some fat or dairy, can ease the burning sensation and is generally easier on the stomach than eating them alone on an empty stomach.
Time to effect
- Minutes: The characteristic burning sensation begins within seconds to about a minute after eating and generally resolves within 10 to 20 minutes as the activated pain receptors desensitize.
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, Gluten-free. Depends on the product: Low-FODMAP.
Satiety
The satiety index is measured on 240 kcal servings. At 29 kcal per 100 g that is 828 g of this, which is not a serving anyone eats — so the index has nothing to say about it.
Environmental footprint
0.5 kg CO2e and 108 litres of freshwater per kg, matched to "Other vegetables" in Poore & Nemecek (2018), Science 360.
Cost band
Cheap — roughly £2.5 per kg, as a band midpoint rather than a price.
Key nutrients
Nutrition per 100g
- Calories: 29
- Protein: 0.9g
- Carbohydrate: 6.5g
- of which sugars: 4.1g
- Fat: 0.4g
- of which saturated: 0g
- Fibre: 2.8g
- Sodium: 3mg
Food vs. supplement
A whole jalapeño provides a modest, self-limiting dose of capsaicin along with genuine vitamin C and other nutrients; capsaicin supplements and high-concentration topical patches deliver much larger, standardized doses used for specific medical purposes, not general nutrition.
Kitchen tip
Remove the pale inner ribs (the placenta), not just the seeds, to cut most of the heat while keeping the flavor, and wear gloves or wash hands with soap immediately after handling.
Common myth
"Eating jalapeños and other spicy peppers causes stomach ulcers." In reality: Peptic ulcers are caused primarily by Helicobacter pylori infection or chronic NSAID use, not spice. Research indicates capsaicin can stimulate gastric mucus production and inhibit acid secretion, and it has even been studied as a protective agent against NSAID-induced ulcers rather than a cause of them.
Recipes that use it
More in Vegetable
In the glossary
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