White Hyacinth Bean

Biji (Grain of the Spleen), the bean that relieves summer heat

The Bencao Gangmu refers to Baekpyeondu (White Hyacinth Bean) as 'Biji (Grain of the Spleen),' meaning the grain of the spleen. This name does not simply mean it is an edible bean, but reflects its identity as a medicinal herb responsible for the harmony of the spleen and stomach. The same text summarizes the effects of Baekpyeondu as follows: 'It harmonizes the middle, descends Qi, tonifies the five viscera, and stops nausea. It relieves summer heat, warms the spleen and stomach, removes damp-heat, and stops thirst.' It further emphasizes the harmonious nature of Baekpyeondu, stating, 'Its energy is fragrant and not pungent, and its nature is warm and mild, reaching a state of central harmony, thus it is the grain of the spleen.'

Today, Baekpyeondu is easily remembered only as a 'health food' or a 'bean rich in dietary fiber.' However, in classical texts, the core of Baekpyeondu lay in its 'prescriptive use' rather than 'edible use.' In the Sipmihyangryeo-eum or Yukhwa-tang from the Gibangyupyeon, Baekpyeondu was used as a key medicinal herb to correct the spleen and stomach disrupted by summer heat and dampness. In particular, Sipmihyangryeo-eum is a prescription for managing abdominal pain, nausea, muscle cramps, irritability, mental confusion, heaviness of the head, and general lethargy; here, Baekpyeondu played the role of 'relieving summer heat, harmonizing the middle, strengthening the spleen, and removing dampness.' In other words, Baekpyeondu was not an ordinary bean, but a medicinal herb that organized the chaos created by summer heat and humidity.

However, there is a paradox here. The 'power to relieve summer heat' of Baekpyeondu is directed against natural summer heat, and does not apply in the same way to the 'artificial cold' created by modern refrigerators and air conditioners. The Bencao Gangmu also warns, quoting Meng Shen, 'It is slightly cold, so people with a cold constitution should not consume it,' and quoting Tao Hongjing, 'Those suffering from alternating chills and fever cannot consume it.' This means that for those whose spleen and stomach are naturally cold and weak, Baekpyeondu may actually increase discomfort. Therefore, how much, who, and how it is used is important, Baekpyeondu is a medicinal herb whose efficacy is properly revealed only within the context of constitution, season, and prescription.

Summary at a Glance

For those who wish to quickly understand what kind of medicinal herb Baekpyeondu is, we have summarized the key points. The table below contains the basic identity, efficacy, and precautions based on classical literature and official medicinal herb information.

Category	Content
Origin	Hanja Name 白扁豆, Scientific Name Lablab purpureus. This herb is verified in the Korea Institute of Oriental Medicine OASIS herbal medicine name information and the Ministry of Food and Drug Safety's herbal medicine quality control guide.
Properties and Meridian Tropism	Its taste and property are recorded as sweet and slightly warm (甘, 微溫), or neutral (性平). It acts on the meridian of the spleen Qi, specifically the foot Taiyin Qi level, and opens the Triple Energizer (Sanjiao).
Representative Aliases	In the Bencao Gangmu, Biji (Grain of the Spleen)it was called. Meaning the grain of the spleen, it represents its identity as a medicinal herb responsible for the harmony of the spleen and stomach, rather than a simple edible bean.
Efficacy Recorded in Literature	According to the Bencao Gangmu, it is recorded to harmonize the middle, descend Qi, tonify the five viscera, stop nausea, detoxify, stop diarrhea, relieve summer heat, warm the spleen and stomach, remove damp-heat, and stop excessive thirst.
Main Ingredients	Modern main components and pharmacological evidence require separate official or academic sources.
Combination & Precautions	Caution is advised for those with a spleen and stomach deficiency-cold constitution or those experiencing alternating chills and fever. Further verification is needed regarding interactions with modern Western medicines and safety during pregnancy and lactation.

Is this medicinal herb right for me?

As Baekpyeondu is called 'Biji (Grain of the Spleen)' in the Bencao Gangmu, it is a medicinal herb focused on managing the spleen and stomach. However, since clear precautions are also passed down in classical records, we will first distinguish who it is suitable for and who should be cautious.

• Generally suitable cases: It has been traditionally considered for cases where digestion is poor due to summer heat and humidity, accompanied by mild diarrhea, nausea, or loss of appetite. It is recorded as a relatively stable herb for those who feel their spleen and stomach functions are slightly sluggish but do not have distinct cold symptoms.
• Cases requiring caution: Caution is required for those whose bodies get cold easily and whose diarrhea manifests with a cold sensation, or those with symptoms of alternating chills and fever. The Bencao Gangmu, quoting Meng Shen, states, 'Those with cold ailments should not eat it,' and Tao Hongjing also recorded that 'those with alternating chills and fever cannot eat it.' Additionally, data regarding modern safety, interactions, pregnancy, and lactation require further verification from official academic sources.
• Cases to avoid: In cases of clear spleen and stomach deficiency-cold, where the abdomen is cold and cold food immediately causes diarrhea or severe abdominal pain, it is not suitable according to classical standards. In such cases, it is common to prioritize other prescriptions that warmly tonify the spleen and stomach over Baekpyeondu.

Practical Q&A

Since Baekpyeondu is both an edible bean and a prescriptive medicinal herb, we often receive questions such as 'Can I just eat it?', 'Which prescriptions is it included in?', and 'Who is it not suitable for?'. Below, we answer questions that naturally arise during consultations, based on contents verified in classical literature and official medicinal herb information.

Can I eat Baekpyeondu just like a regular food?

Classically, it is recorded as a herb used for both food and medicine. The Bencao Gangmu describes various methods of use, such as chewing it raw, drinking it as a boiled juice, roasting it, or using it after removing the skin. However, these records are traditional usage examples and are not unconditionally applicable depending on an individual's modern constitution or consumption situation. It is safest to determine the specific form of intake and dosage through a consultation.

Does 'relieving summer heat' apply only to the summer season?

The Bencao Gangmu records that Hyacinth Bean (Baekpyeondu) “relieves summer heat (暑), warms the spleen and stomach, and removes damp-heat (濕熱).” Here, ‘summer heat’ often refers to climatic factors in traditional medicine where external heat and humidity combine during the summer. In contrast, ‘artificial cold (寒)’ caused by air conditioning or cold foods follows a completely different pathway, so the same medicinal herb may not necessarily be appropriate. It is important to first distinguish whether the cause of the symptoms is heat and dampness or cold and dampness.

Which classical prescriptions include Hyacinth Bean?

Hyacinth Bean plays a supportive yet core role in several classical prescriptions. In Sipmi Hyangryeo-eum and Yukhwa-tang from the Gifang Yubyeon, roasted Hyacinth Bean is used to relieve summer heat, harmonize the middle burner, and stop diarrhea. In Eunbaek-san and Namseong-eum from the Dongui Bogam, it is included as a supportive herb in prescriptions to treat stiffness or loss of appetite in children. In Baekpyeondu-san from the Boje Bonsifang, it is used to strengthen the spleen and transform phlegm for cases of chronic cough and excessive sputum.

Who should use it with caution?

Classical records provide clear warnings. Meng Shen stated, “It is slightly cold, so those with a cold constitution (患冷人) should not consume it,” and Tao Hongjing stated, “Those with alternating chills and fever (寒熱往來) should not consume it.” In other words, Hyacinth Bean should be used cautiously for those with a cold and weak spleen and stomach, symptoms where chills and fever alternate, or clear cold symptoms. This is because while Hyacinth Bean harmonizes the spleen and stomach, its nature is cold or close to neutral, which may cause discomfort if it does not match the individual's constitution.

Are there any precautions when using it with Western medicine?

To date, specific data regarding the interactions between Hyacinth Bean and Western medicine has not been secured from official or academic sources. Therefore, this area requires verification. If you are taking Western medicine or suffering from a chronic disease, please be sure to ask during your consultation before using Hyacinth Bean in the form of a prescription or restorative herbal medicine.

Can it be used during pregnancy or breastfeeding?

Since official or academic evidence regarding safety during pregnancy and breastfeeding is also currently insufficient, it requires verificationand must remain as such. While it has been treated classically as a type of edible bean, pregnancy and breastfeeding are periods when an individual's condition is sensitive, so it is appropriate to make a determination through a consultation.

Relationship with Other Medicinal Herbs (Yakdae/Pairing)

Hyacinth Bean is rarely used alone. Its properties are refined only when combined with other medicinal herbs; in tradition, such pairs are called “Yakdae (medicinal pairs).” Especially in prescriptions to relieve summer heat or harmonize the spleen and stomach, Hyacinth Bean is used with other aromatic herbs, playing a supportive role in stabilizing the direction of each ingredient within a single prescription.

• Hyacinth Bean + Elsholtzia ciliata, etc. — Sipmi Hyangryeo-eum Gifang Yubyeon: Combined with Elsholtzia ciliata, Ginseng, Citrus peel, Atractylodes macrocephala, Magnolia bark, Quince, Poria cocos, Licorice, and Astragalus, it has been traditionally used for “all summer-heat, abdominal pain, cholera, muscle spasms, irritability, mental confusion, heaviness of the head, and physical fatigue.” Here, Hyacinth Bean is used roasted to relieve summer heat, harmonize the middle burner, and strengthen the spleen while removing dampness.
• Hyacinth Bean + Ginseng, Pinellia ternata, Agastache rugosa, etc. — Yukhwa-tang Gifang Yubyeon: A prescription used for cholera, muscle spasms, vomiting, and diarrhea; Hyacinth Bean is used in roasted form to harmonize the middle burner and stop diarrhea, and to regulate the spleen and stomach.
• Hyacinth Bean + Lotus seed, Poria cocos, Gastrodia elata, etc. — Eunbaek-san Dongui Bogam: Used for chronic infantile convulsions and spleen/stomach weakness in children; Hyacinth Bean is included as a supportive herb to assist the stomach and strengthen the spleen.
• Hyacinth Bean + Ginger, Pinellia ternata, Ginseng, etc. — Baekpyeondusan 《Pu-je-bon-si-bang》: Used for chronic cough, lung atrophy (pyewi), large amounts of white phlegm, chest tightness, and loss of appetite; Baekpyeondu, when steamed over rice, tonifies the lungs and spleen and transforms phlegm.

Regarding combination contraindications, no direct records of incompatible interactions have been identified in classical texts. However, since Baekpyeondu itself possesses "warm and peaceful (溫平)" and "neutral (中和)" properties, in cases of clear cold syndromes (寒證) or spleen and stomach deficiency-cold (脾胃虛寒), it is important to consider it carefully within the context of the overall prescription rather than relying on it alone without other medicinal herbs.

In what form is it consumed?

In the Bencao Gangmu, Baekpyeondu is recorded as an ingredient used for both food and medicine. However, not all usage methods found in classical texts are suitable for home application today, so I will explain them by category.

• Brewing as tea, Not common While the form of "boiling the juice for drinking (煮汁飲)" exists in classical texts, this is a prescriptive method for specific poisonings or acute symptoms. It is not traditionally recorded for steady consumption as a daily health tea.

• Preparing as food, Possible Both "boiling for food (煮食)" and "chewing raw (生嚼)" appear in the Bencao Gangmu. In other words, there were classical examples of boiling or chewing it raw, but safety and intake standards based on modern food regulations currently need to be verified.

• Decocting as herbal medicine, Possible Examples of decoction using "roasted Baekpyeondu (炒白扁豆)" for "water decoction (水煎服)" are confirmed in prescriptions such as Simmihyangryu-eum and Yukhwa-tang from the 《Gi-bang Ryu-pyeon》. This form is used under the prescription of a Korean medicine doctor.

• Use in professional prescriptions, Possible It is used as a component in prescriptions related to the spleen, stomach, pediatrics, and respiration, such as Eunbaeksan and Namseong-eum in the Dongui Bogam, and Baekpyeondusan in the 《Pu-je Bon-si-bang》. The duration of intake, dosage, and concurrent use must be determined through consultation with a Korean medicine doctor.

Interactions and Safety During Use

Baekpyeondu is recorded as "non-toxic (無毒)" in the Bencao Gangmu and is an ingredient used for both food and medicine, but this does not mean it is unconditionally safe for everyone. Clear precautions are passed down in classical literature, and modern safety data currently require further verification.

Precautions from Classical Texts

• Records of Meng Zhen cited in the 《Bencao Gangmu》: "Slightly cold, those suffering from cold should not eat it", This means Baekpyeondu may be slightly cold (微寒) and may not be suitable for those with a cold constitution (患冷人).
• Records of Tao Hongjing cited in the 《Bencao Gangmu》: "Those suffering from alternating chills and fever should not eat it", This is a record stating it should be avoided for patients with alternating chills and fever (寒熱往來).

In other words, from a Korean medicine perspective, spleen and stomach deficiency-cold (脾胃虛寒), a cold constitution, or symptoms of alternating chills and feverare conditions where Baekpyeondu must be handled with caution. While it has the power to harmonize the spleen and stomach, so much so that the Bencao Gangmu calls it the 'grain of the spleen', that power is neutral (中和)in nature. If a constitution or symptom is already heavily skewed toward one side, it may act in a direction other than restoring that balance.

Modern Safety and Interactions

Web search is temporarily blocked (429 Too Many Requests), so official or academic sources could not be secured for the following items.

• Interactions when used with Western medicine
• Safety during pregnancy and breastfeeding
• Modern clinical reports of side effects
• Toxicity data for long-term use
• Precautions for specific conditions (diabetes, autoimmune diseases, digestive diseases, etc.)

Therefore, the above items require verification. If you plan to consume Baekpyeondu as a standalone food or use it together with other Korean herbal medicines or Western medicines, it is safe to decide only after consulting with a Korean medicine doctor.

Information that is helpful to provide during consultation

• Western medicines or health functional foods currently being taken
• Pregnancy or breastfeeding status
• General constitution (whether you tend to feel cold or feel the heat easily)
• Tendency of spleen and stomach-related symptoms, such as diarrhea, abdominal coldness, or loss of appetite
• Presence of alternating chills and fever (feeling of repeating cold and hot sensations)

The safe use of Baekpyeondu starts not with "It's an edible bean, so it should be fine," but with "Does my current constitution and symptoms require neutralization?"Since this judgment must be made by looking at the individual's overall condition, please confirm the specific use, dosage, and form through a consultation.

If you experience these symptoms

In these cases, please stop the consultation and let us know

Baekpyeondu is recorded as 'non-toxic' in classical texts and is used for both food and medicine, but this does not mean it is unconditionally safe for all constitutions and conditions. The following signals are known warning signs that may appear during use; if these changes occur, it is important to inform your attending Korean medicine doctor first rather than adjusting the dose or stopping on your own.

• If the abdomen feels colder and diarrhea becomes more frequent Contrary to the way Baekpyeondu harmonizes the spleen and stomach, if digestion becomes more uncomfortable or stools become looser, the constitution, symptoms, or formulation may not be a match.
• If the body becomes colder and hands and feet feel chilly As stated in classical texts ('those suffering from cold should not eat it'), in constitutions with original cold symptoms or Spleen-Stomach Deficiency-Cold, Baekpyeondu may instead amplify the coldness.
• If you experience fluctuating fever or recurring chills and fever As noted in records stating 'those suffering from alternating chills and fever should not eat this,' it may not be suitable for conditions involving alternating chills and fever (Han-yeol-wang-rae).
• If new nausea or vomiting occurs, or if existing vomiting worsens While Baekpyeondu is used to stop vomiting, symptoms may progress in the opposite direction depending on other medical conditions or inappropriate combinations of ingredients.
• If systemic allergic reactions such as hives, itching, or difficulty breathing occur after intake As there may be individual sensitivity to edible beans, stop use immediately and visit a medical institution.

These signs usually appear when the dosage, constitution, or combined herbal ingredients are not a match. Even if the symptoms are mild, please inform your attending Korean medicine doctor if they persist. In urgent cases, such as difficulty breathing or systemic allergic reactions, please use an emergency medical institution (or call 119).

Differences from other restorative medicines

Baekpyeondu occupies a unique position even within the general category of 'restorative medicine' (Boyak). This is because it does not simply supplement energy, but works to assist the transport and transformation of the spleen and stomach and resolve dampness. Therefore, its context of use differs from typical restorative medicines like Gongjindan or Gyeongokgo.

Gongjindan is a prescription focused on supplementing overall vital energy and treating deficiency syndromes, often used for long-term weakness and aging-related symptoms. Gyeongokgo also supplements qi and blood and improves complexion, primarily linked to qi and blood deficiency in women or postpartum recovery. These are typical examples of restorative medicine that 'fill what is lacking.'

In contrast, Baekpyeondu is closer to 'restoring a function that is not working' rather than 'filling a deficiency.' This is why it was called 'the grain of the spleen' in the Bencao Gangmu. When the spleen and stomach become sluggish due to dampness or damp-heat, leading to slow digestion and recurring nausea or diarrhea, Baekpyeondu plays a supporting role in stabilizing the center alongside other ingredients. As seen in prescriptions like Eunbaeksan or Simmihyangryeo-eum, it appears more frequently in treating slow growth in children or acute vomiting and diarrhea during the summer.

Therefore, it is appropriate to understand Baekpyeondu as an ingredient used for short periods in specific situations to harmonize the spleen and stomach and resolve dampness, rather than taking it long-term as a standalone restorative medicine. It is safest to determine which restorative medicine you need, or whether a prescription containing Baekpyeondu is right for you, after evaluating your constitution and current symptoms. You may review this during your consultation.

References

1. Evidence materials for Baekpyeondu 1: data.go.kr evidence materials.
2. Evidence materials for Baekpyeondu 2: Korea Institute of Korean Medicine official data.
3. Evidence materials for Baekpyeondu 3: National Institute of Food and Drug Safety Evaluation herbal medicine data.

---

If you would like to check if this medicinal herb is right for you or which prescription it should be used with, please leave a medical inquiry. For those who find it difficult to visit the clinic, non-face-to-face consultations are available; we will provide guidance after first reviewing your current condition and current medications.