Horse beans are a variety of fava bean, one of the oldest cultivated legumes in the world. They belong to the species Vicia faba and are distinguished from other fava beans by their smaller seeds and more numerous pods. While the term “horse bean” sometimes gets used loosely as a synonym for any fava bean, it technically refers to a specific botanical variety with a long history in both human nutrition and animal feed.
How Horse Beans Differ From Broad Beans
The fava bean species has three recognized varieties, and understanding these clears up most of the naming confusion. The large-seeded type most people picture when they hear “fava bean” or “broad bean” is Vicia faba var. faba (also called the Windsor bean). It produces one or two large pods with big, flat seeds. Horse beans, classified as Vicia faba var. equina, are the medium-seeded variety. They grow more pods per plant, but each pod contains smaller seeds than the broad bean. The third variety, the tick bean or bell bean (var. minuta), has the smallest seeds of all, with the most pods clustered along the stem.
In practice, these names overlap constantly. Farmers in the UK and parts of Europe often call the smaller-seeded types “field beans” because they’re grown as a field crop rather than a garden vegetable. Grocery stores in North America tend to label everything “fava beans.” If you see dried beans sold as horse beans, expect seeds that are rounder and smaller than the broad, flat favas you might find fresh at a farmers’ market.
Nutritional Profile
Horse beans pack a serious nutritional punch, especially for a plant food. Dried horse beans contain roughly 26 to 29% protein by weight, which puts them in the same league as lentils and chickpeas. They also provide 4 to 7% crude fiber along with meaningful amounts of iron, folate, and B vitamins. That protein content is built primarily on two types: globulins make up about 61% of the total protein, with albumins contributing another 20%. This combination gives horse beans a well-rounded amino acid profile, though like most legumes, they’re relatively low in the sulfur-containing amino acids found in grains and animal products.
Pairing horse beans with rice, bread, or another grain fills in those amino acid gaps, making the combination a complete protein source. This is exactly what traditional cuisines in the Middle East, North Africa, and Ethiopia have done for centuries.
A Natural Source of L-Dopa
One of the more surprising things about horse beans (and fava beans generally) is that they contain L-dopa, the direct precursor to dopamine in the brain. This is the same compound used as the standard medication for Parkinson’s disease. Sprouted fava beans are particularly rich in it, with studies measuring concentrations between 0.65 and 1.51 mg/mL in extracts from fresh and dried sprouted beans.
Research published in the Journal of Clinical and Diagnostic Research found that fava bean consumption increased L-dopa levels in the blood, with noticeable improvements in motor performance among Parkinson’s patients and no reported side effects. This doesn’t mean horse beans are a replacement for medication, but it does explain why researchers continue to investigate them as a dietary supplement for people with dopamine-related conditions.
Antinutrients and How to Handle Them
Like most legumes, horse beans contain compounds that can interfere with nutrient absorption if the beans aren’t properly prepared. Phytic acid binds to minerals like iron and zinc, reducing how much your body can absorb. Tannins, concentrated especially in darker-skinned varieties, can give the beans a bitter taste and further reduce protein digestibility. The beans also contain protease inhibitors that interfere with enzymes your body uses to break down protein.
The good news is that basic kitchen prep eliminates most of these concerns. Soaking dried horse beans for 4 to 6 hours, then boiling them vigorously for 10 to 15 minutes before reducing to a simmer, dramatically reduces antinutrient levels. Germination (sprouting the beans for 24 to 72 hours) is even more effective, significantly decreasing phytic acid, polyphenols, and condensed tannins while also reducing protease inhibitor activity. Simply cooking them thoroughly until they’re soft is enough for everyday purposes.
The Favism Risk
There is one serious health concern specific to fava beans, including horse beans. People with G6PD deficiency, a genetic enzyme disorder affecting roughly 400 million people worldwide (most commonly in Mediterranean, African, and Southeast Asian populations), can develop a dangerous reaction called favism after eating these beans. Horse beans contain two compounds, vicine and convicine, that get converted in the body into highly reactive molecules. These molecules generate a flood of oxidative stress that damages red blood cells, potentially triggering hemolytic anemia, where red blood cells break down faster than the body can replace them.
Symptoms can include fatigue, dark urine, jaundice, and in severe cases, the reaction requires medical attention. If you know you have G6PD deficiency or it runs in your family, horse beans and all fava bean varieties should be avoided entirely. Cooking does not eliminate vicine and convicine.
Use in Animal Feed
Horse beans have been fed to livestock for as long as they’ve been cultivated, and the name “horse bean” likely reflects this history. Their high protein content (21 to 34% of dry matter, depending on the variety) makes them a viable alternative to soybean meal in animal diets. Research shows that raw horse beans can replace soybean meal in cow concentrate feed at levels around 175 g/kg and in lamb diets at up to 300 g/kg without affecting growth or carcass quality. Some studies pushed inclusion rates much higher, feeding lambs diets with over 500 g/kg horse beans, with no negative effects on carcass yield.
Poultry are more sensitive to the antinutrients in raw horse beans. Laying hens can generally tolerate inclusion rates up to about 100 to 110 g/kg of their diet, but higher levels (165 g/kg and above) tend to reduce egg production and quality. Processing the beans before feeding, through heat treatment or dehulling, allows for higher inclusion rates.
Benefits for Soil and Farming
Horse beans are a legume, which means they form a partnership with soil bacteria that pull nitrogen from the air and convert it into a form plants can use. This biological nitrogen fixation supplies about 80% of the horse bean plant’s own nitrogen needs. Depending on growing conditions, the crop can fix up to 200 kg of nitrogen per hectare, and roughly half of that stays in the soil after harvest. That leftover nitrogen feeds whatever crop comes next, reducing the need for synthetic fertilizers.
This makes horse beans particularly valuable in crop rotation systems. They help break disease cycles in cereal crops and suppress weeds. Research from Ethiopia found that intercropping wheat with fava beans reduced weed growth and disease severity while increasing overall land productivity by 22% compared to growing either crop alone. Studies have also shown that fava beans boost the yield of subsequent cereal crops more effectively than other legumes, which is why they remain a cornerstone of sustainable farming in Europe, North Africa, and East Africa.