Green beans (Phaseolus vulgaris)

Botanical name

Phaseolus vulgarislegumes (Fabaceae); French bean: var. nanus

is used

The unripe podincluding the young kernels, always cooked

The taste

Grassy-green, slightly sweetcooked tender with a bite

Origin

Central and South Americasince the 16th century in Europe

Known for

Phasin - poisonous when rawplus folate, vitamin K and fiber

season

July to SeptemberEarly stock available from June, otherwise imports

On this page

Origin To use Ingredients Reinforced combinations & what clashes In the kitchen As a home remedy Ayurveda & TCM Warning notices Related to the topic Sources

In short

Green beans are the young pods of the common bean – the same plant whose mature beans are stored as dried beans. They are low in calories, provide fiber, folate, and vitamin K, and are a staple in every German kitchen in late summer. However, when raw, they contain the protein... Phasin, which can cause stomach aches and vomiting even in small amounts. Green beans are therefore always cooked thoroughly – with a sprig of savory, in the classic way.

OriginFrom the Andes to the kitchen garden

The common bean was domesticated twice independently – in Mexico and in the Andes.

Wild garden beans grow from Mexico to Argentina. As early as 8,000 years ago, people in Central America and the Andes began cultivating them, together with maize and squash, as the "three sisters": the maize serves as a trellis, the beans fix nitrogen, and the squash shades the soil. Beans arrived in Europe with Spanish ships in the 16th century and quickly displaced the old broad bean.

One distinguishes the low Bush bean (var. nanus) and the climbing Pole bean, which climbs up to three meters high. Commercially available varieties include snap beans, princess beans, cut beans, and yellow wax beans. The climbing scarlet runner bean, however, is a separate species (Phaseolus coccineus) - and also poisonous when raw.

To useWhat green beans can do for you

According to the USDA, 100g of raw green beans contain only about 31 kcal, but 2.7g of vitamin D. Dietary fiber, 1.8 g protein, approximately 33 µg Folate, 12 mg vitamin C and approximately 43 µg Vitamin K A 200g serving covers the estimated daily requirement of vitamin K. It also contains potassium, magnesium, and carotenoids.

The fiber in green beans is filling, promotes regular digestion, and makes them a satisfying food with low energy intake. Large observational studies link high consumption of vegetables and legumes with lower rates of cardiovascular disease—however, there is no specific evidence for green beans alone. They are simply a nutrient-rich, light summer vegetable.

The most important point is safety: Phasin Phasin is a lectin that binds to the intestinal lining. Even a few raw beans can cause nausea, abdominal cramps, vomiting, and diarrhea after two to three hours; children are particularly vulnerable due to their low weight. Heat destroys phasin, but according to the German Federal Institute for Risk Assessment (BfR), simply boiling, gently steaming, or braising is insufficient.

at least 10–15 minutes.Boil vigorously - never eat raw

approx. 43 µgVitamin K per 100 g

approx. 33 µgFolate per 100 g

31 kcalper 100 g

IngredientsThis is what's in green beans

Green beans contain carbohydrates (mainly sugars and starch), dietary fiber such as pectins and cellulose, protein including the lectin phasin, flavonoids such as quercetin and kaempferol glycosides, chlorophyll, beta-carotene, lutein as well as folate, vitamin K, vitamin C, potassium, magnesium, calcium and iron.

During cooking, some vitamin C and folate leach into the water. Discard the cooking water anyway, as it also contains traces of phasin. Vitamin K, carotenoids, and dietary fiber are heat-stable.

Enhanced combinationsWhat makes green beans stronger

Green beans need heat, some fat, and a spicy herb.

herb

with Savory

The classic combination - spicy and easily digestible.

Fat

with butter or olive oil

Vitamin K and carotenoids are fat-soluble.

acid

with vinegar or lemon

For the bean salad - but only after cooking.

nuts

with almonds

Haricots verts amandine.

Summer

with Tomatoes & garlic

Mediterranean style braised.

protein

with Potatoes & Egg

Rhenish or as Salade Niçoise.

What contradicts itselfIt's best to avoid these combinations.

Raw

not snacking on raw

Phasin - also keep an eye on children in the garden.

Dampening

not only steam or braise

Not enough heat for phasin.

Blanching

not Eat only blanched

Three minutes are not enough for detoxification.

Cooking water

not reuse

Always throw it away.

Low temperature

not in the slow cooker

Below 100 °C, lectin remains active.

Baking soda

not into the cooking water

It remains green, but vitamins are lost.

In the kitchenWhere they belong

Beans with savoryTossed in butter.
Bean saladWith onions and vinegar.
Green bean stewWith potatoes and carrots.
Bacon beansCooked in a bundle.
Salade niçoiseWith potatoes, egg and olives.
Haricots vertsWith roasted almonds.
Pears, beans and baconA classic from Northern Germany.
Braised beansWith tomatoes and garlic.
curryWith coconut milk and lentils.
Wok beansFirst boiled, then seared.

Rule of thumb: Trim the ends and cook the beans in plenty of rapidly boiling salted water for at least 10 to 15 minutes, until tender – thicker, older beans will take longer. The German Federal Institute for Risk Assessment (BfR) even recommends up to 30 minutes for fresh beans in its lectin statement. Cook frozen beans just as thoroughly.

As a home remedyBean salad with savory for light summer cuisine

Here's how it works

Bean salad

Clean 500g of green beans and cook them with a sprig of savory in boiling salted water for 12 to 15 minutes until soft.
Drain, discard cooking water, briefly rinse beans with cold water.
Mix a finely diced shallot with 2 tablespoons of wine vinegar, 3 tablespoons of oil, salt and pepper.
Mix in the still lukewarm beans and let them soak for at least 30 minutes.

For what

A light, fiber-rich side dish for summer. Savory is traditionally added to legumes to prevent bloating – an anecdotal practice not supported by studies, but it tastes good.

Crowd

Serve 150 to 200 g per person as a side dish. The salad will keep for two days in the refrigerator.

Ayurveda & TCMWhat the old systems say

Ayurveda

In Ayurveda, green beans are considered sweet and astringent, cooling and light – balancing Pitta and Kapha. For those with a Vata constitution, they should be thoroughly cooked and eaten with warming spices such as cumin or ginger.

Traditional Chinese Medicine

Western Traditional Chinese Medicine (TCM) classifies green beans as sweet and neutral. They are said to strengthen the digestive system (spleen and stomach) and eliminate dampness – especially when cooked and with a flavorful herb like savory.

Warning noticesWhen you should be careful

Please note

Never raw: Even small amounts of phasin cause nausea, vomiting, abdominal cramps, and diarrhea; in severe cases, bloody diarrhea and circulatory problems. If raw beans are ingested—especially by children—call poison control immediately.
Ferment: Boil vigorously, not just steam, simmer or cook at a low temperature; discard the cooking water.
Blood thinners: When taking vitamin K antagonists like Marcumar, eat regular amounts instead of suddenly eating large quantities.
Flatulence: For those with a sensitive digestive system, smaller portions are recommended, cooked thoroughly and with savory or caraway.
Allergy: Cross-reactions with other legumes such as peas, peanuts or soy are rare and possible.

This page provides information and does not replace medical advice. If symptoms persist, please consult a doctor.

SourcesWhat is this based on?

USDA FoodData Central: Beans, snap, green, raw.
Federal Institute for Risk Assessment (BfR): Lectins in plant-based foods: Is there a health risk? Statement 03/2024 dated January 23, 2024.
Federal Institute for Risk Assessment (BfR): Beans should only be enjoyed cooked. Press release dated July 19, 2021.
Rodhouse JC, Haugh CA, Roberts D, Gilbert RJ. Red kidney bean poisoning in the UK: an analysis of 50 suspected incidents between 1976 and 1989. Epidemiology and Infection 1990; 105(3): 485–491.
Consumer Advice Center Bremen: Green beans - when prepared correctly, a nutrient-rich legume. Press release from July 25, 2023.
Federal Centre for Nutrition (BZfE): Pulses: From shopping to the kitchen.