Green Beans
Food · Vegetable · Food, Typed Supps
Green beans are a crunchy veggie that gives you fiber, vitamin C, and a bone-friendly vitamin called K — just make sure they're cooked, not raw.
Stage by stage
- Chewing & Swallowing (Mouth): Chewing breaks down the fibrous pods, beginning to release their vitamin C, vitamin K, and folate for digestion.
- Stomach Breakdown (Stomach): Stomach acid and enzymes further break down the bean's plant fibres and proteins, freeing bound nutrients for absorption downstream.
- Nutrient Absorption (Small Intestine): In the small intestine, fat-soluble vitamin K and water-soluble vitamin C, folate, and manganese are absorbed into the bloodstream, with vitamin K uptake enhanced by any fat eaten alongside the beans.
- Bone & Clotting Support (Bone & Blood): Absorbed vitamin K travels to the liver and bones, where it activates proteins essential for normal blood clotting and bone mineralisation.
Timing
Because vitamin K is fat-soluble, eating green beans with a source of fat, such as olive oil or nuts, improves its absorption.
Time to effect
- Hours to weeks: Water-soluble nutrients like vitamin C and folate are absorbed within a few hours of eating, while vitamin K's contribution to blood clotting and bone health depends on consistent intake over 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, Gluten-free.
In season
June to September in the northern hemisphere, December to March in the southern.
Satiety
The satiety index is measured on 240 kcal servings. At 30 kcal per 100 g that is 803 g of this, which is not a serving anyone eats — so the index has nothing to say about it.
Environmental footprint
1 kg CO2e and 397 litres of freshwater per kg, matched to "Peas" in Poore & Nemecek (2018), Science 360.
Cost band
Cheap — roughly £2.2 per kg, as a band midpoint rather than a price.
Key nutrients
Nutrition per 100g
- Calories: 29.9
- Protein: 2.1g
- Carbohydrate: 3.9g
- of which sugars: 3g
- Fat: 0g
- of which saturated: 0g
- Fibre: 3.2g
- Sodium: 0mg
Food vs. supplement
Green beans provide vitamin K, C, manganese, and folate together with fiber and plant compounds, a package no single-nutrient supplement replicates.
Kitchen tip
Steam or stir-fry green beans until just tender-crisp rather than boiling them for a long time; this preserves more vitamin C and ensures they're cooked enough to neutralize their natural lectin.
Common myth
"Raw green beans are healthier than cooked ones because cooking destroys nutrients." In reality: Raw or undercooked green beans contain phytohaemagglutinin, a lectin that can cause nausea, vomiting, and diarrhea from as few as four or five raw pods; adequate cooking inactivates this toxin and makes the beans safe, while only modestly reducing their heat-sensitive vitamin C content.
Recipes that use it
More in Vegetable
In the glossary
Sources