Kelp and Sargassum Simmered with Soybeans: A Traditional Medicinal Soup

Kelp and Sargassum Simmered with Soybeans

Introduction to Medicinal Diet

Kunbu (Laminaria japonica, commonly known as kelp) and Haizao (Sargassum fusiforme, commonly known as seaweed) stewed with soybeans (Glycine max) is a classic therapeutic dish originating from the southeastern coastal regions of China, with especially widespread folk use in Guangdong and Fujian provinces. This medicinal food skillfully combines oceanic kelp and seaweed with land-grown soybeans, occupying a unique position within Lingnan soup culture and being praised as a “dual marine treasure meeting golden earth essence” for health preservation. In this dish’s name, “Kunbu” refers to what is now commonly called kelp (Laminaria japonica), while “Haizao” refers to marine algae such as Sargassum fusiforme.

This medicinal dietary recipe can be traced back to the Tang and Song dynasties, when coastal residents began using marine algae to relieve neck masses and other discomforts caused by environmental changes. The *Compendium of Materia Medica* records that *Kunbu* (Laminaria japonica, Kelp) and *Haizao* (Sargassum, Seaweed) are key herbs for treating goiter (known as “yingliu” in TCM, corresponding to thyroid enlargement in modern medicine). The addition of soybeans (Glycine max) not only enriches the flavor but also enhances the function of tonifying the middle and supplementing qi. This allows the recipe to expel pathogenic factors without damaging the upright qi, making it a nourishing and suitable dietary therapy for people of all ages.

Actions of Medicinal Diet

The core efficacy of Kelp and Seaweed stewed with Soybean is to “dissolve phlegm, soften hardness, promote urination, and reduce edema.” It can effectively soften and dissipate various nodules and masses formed by binding of phlegm-turbidity and blood stasis within the body, and is especially beneficial as an adjuvant therapy for thyroid nodules and lymphadenopathy of the neck. At the same time, its action of promoting urination and percolating dampness helps the body expel excess fluid, offering significant improvement for symptoms such as edema and difficult urination.

From the perspective of modern nutrition, kelp (Laminaria japonica) and seaweed (Sargassum) are rich in iodine, alginate, and various minerals, which help regulate thyroid function and promote metabolism. Soybeans (Glycine max) are abundant in high-quality plant protein and soy isoflavones, offering antioxidant and blood lipid-regulating effects. The synergistic action of these three ingredients enables this medicinal diet to dissipate nodules while enhancing immune function and improving overall health.

The Role of Traditional Chinese Medicine

In TCM theory, both Kunbu (Laminaria japonica / Kelp) and Haizao (Sargassum / Seaweed) are classified as “salty and cold” in nature, entering the Liver, Stomach, and Kidney meridians. Since saltiness softens hardness and coldness clears heat, their combined use has a direct therapeutic effect on “goiter” and “scrofula” (corresponding to thyroid enlargement and tuberculous lymphadenitis in modern medicine), conditions arising from Liver qi depression binding with phlegm-fire. Kunbu excels at transforming phlegm and softening hardness, while Haizao tends to promote urination and dissipate masses. The two complement each other, working like a pair of swords that join forces to directly attack the disease focus.

In this formula, the soybean (Glycine max) plays a vital role as a “harmonizer”. Its flavor is sweet and its nature is neutral, entering the Spleen (SP) and Large Intestine (LI) meridians. It is able to fortify the spleen, broaden the center, moisten dryness, and disperse water. The inclusion of soybean in the formula serves two purposes: on one hand, it restrains the cold nature of Kunbu (Ecklonia kurome, kelp) and Haizao (Sargassum, seaweed), thereby protecting the function of the spleen and stomach from damage; on the other hand, as the spleen and stomach are the acquired foundation, soybean supplements the spleen’s qi and blood, providing a source for their generation and transformation, thereby enhancing the body’s ability to expel pathogens outward. As the classic saying goes, “When you see phlegm, do not treat the phlegm; treat the spleen as the correct treatment.” The application of soybean embodies this TCM wisdom.

Mechanism of Formula Composition

The whole formula uses *Kunbu* (Laminariae Thallus / Eckloniae Thallus, kelp or seaweed) and *Haizao* (Sargassum, seaweed) as the sovereign herbs to transform phlegm and soften hardness, treating the manifestation. *Huangdou* (Glycine max, soybean) serves as the minister herb to tonify the spleen and boost qi, treating the root cause. *Jiang* (Zingiberis Rhizoma Recens, fresh ginger) and *Zao* (Ziziphi Fructus, jujube) act as adjuvants to harmonize the nutritive and defensive phases. Together, they accomplish the effects of softening hardness and dissipating masses, supporting upright qi and dispelling pathogenic factors. The entire formula is structured with rigorous logic, combining attack and supplement, reflecting the holistic concept of TCM dietary therapy.

Indications

For individuals primarily presenting with “nodules” such as thyroid nodules, goiter, lymph node tuberculosis, or breast hyperplasia, this medicinal diet serves as an excellent daily supportive soup. It is particularly beneficial for professionals experiencing neck discomfort due to high work stress and emotional fluctuations, as well as women undergoing puberty or menopause—periods marked by greater hormonal fluctuations and increased susceptibility to thyroid issues.

In addition, for individuals with hypertension, hyperlipidemia, and those needing weight management, the medicinal soup of kelp, seaweed, and soybeans (Kunbu, Haizao, and Huangdou) is also a good choice. The alginic acid in kelp helps expel excess sodium ions from the body, aiding in blood pressure reduction; the soy lecithin in soybeans helps lower bad cholesterol. For people with edema-type obesity, this medicinal diet’s property of promoting diuresis and reducing edema can also bring positive improvements.

Contraindicated Populations

Although Kunbu (Laminaria) and Haizao (Sargassum) decocted with soybeans has remarkable efficacy, it is not suitable for everyone. First, individuals with hyperthyroidism (thyroid overactivity) must strictly avoid it. Because Kunbu and Haizao are rich in iodine, excessive iodine intake can aggravate hyperthyroidism, exacerbating symptoms such as palpitations, hand tremors, and sweating. Similarly, those allergic to iodine should also avoid consumption.

Secondly, individuals with severe Spleen and Stomach Vacuity Cold (Spleen and Stomach Deficiency Cold), such as those who frequently experience cold pain in the stomach, loose stools, aversion to cold, and preference for warmth, should not consume this medicinal diet alone or in excess. Although the formula contains soybeans (Glycine max) to harmonize, the cold nature of kelp (Laminaria japonica) and seaweed (Sargassum) may still irritate the weakened Spleen and Stomach. It is recommended that such individuals increase the amount of fresh ginger (Zingiber officinale) and pair it with warming ingredients like lamb (sheep meat) or pepper (Piper nigrum) to counteract its cold nature.

Ingredient formula ratios

The ingredients required to prepare Kunbu Haizao Huangdou (Laminaria japonica, Sargassum, and soybean) soup include: dried Kunbu (Laminaria japonica, kelp) 30 g, dried Haizao (Sargassum fusiforme, hijiki seaweed) 20 g, Huangdou (Glycine max, soybean) 60 g, Shengjiang (Zingiber officinale, fresh ginger) 3 slices (approx. 10 g), Hongzao (Ziziphus jujuba, red date) 5 pieces (pitted). A pinch of salt or rock sugar may be added for seasoning according to personal taste.

The specific proportioning principle is as follows: the amount of soybean (Glycine max) should be appropriately greater than the total amount of kelp (Laminariae Thallus / Eckloniae Thallus) and seaweed (Sargassum) to fully exert its effects of tonifying the Spleen and supplementing Qi, as well as moderating the gentle nature of the medicinal combination. The dry kelp to seaweed ratio is best maintained at approximately 3:2. This ensures the efficacy of softening hardness and dissipating masses, while avoiding damage to the Spleen and Stomach due to excessive cold nature. Fresh ginger (Zingiberis Rhizoma Recens) and red dates (Ziziphi Fructus) are used as adjuncts; their amounts should not be excessive, serving only to warm the Middle and dispel Cold, and to harmonize the various medicinals.

Preparation method

Step 1: Prepare the ingredients. Soak the dried kelp (Laminariae Thallus) and dried seaweed (Sargassi Thallus) in fresh water for approximately 30 minutes, allowing them to fully rehydrate and expand. Then rinse thoroughly under running water to remove surface impurities and salt. Soak the soybeans (Glycine max) in fresh water for at least 4 hours in advance, preferably overnight, so they become fully hydrated and easier to soften and release flavor during simmering. Slice the fresh ginger (Zingiber officinale rhizome) and remove the pits from the Chinese dates (Ziziphus jujuba), then set aside.

Step 2: Blanch to remove fishy odor. Cut the rehydrated Laminaria (kelp) into long strips or small pieces, and cut the Sargassum (seaweed) into moderate segments. Place the cut Laminaria and Sargassum into boiling water and blanch for about 2 minutes, then remove and drain. This step effectively removes the fishy taste and excess iodine from seaweed ingredients, resulting in a purer flavor for the soup.

Step 3: Simmer the soup. Take a stew pot or clay pot, and place the soaked soybeans (Glycine max), blanched kelp (Laminaria japonica) and seaweed (Sargassum), ginger slices (Zingiber officinale), and red dates (Ziziphus jujuba) into the pot. Add enough clean water to fully submerge all ingredients, with about two finger-widths of water above them. Cover the pot, bring to a boil over high heat, then reduce to low heat and simmer slowly for approximately 1.5 to 2 hours.

Step 4: Season and finish. When the soybeans are soft and tender, the soup turns milky white, and the aroma fills the air, add a small amount of table salt or rock sugar to taste according to personal preference. Note that salt should not be added too early, as it may affect the softening of ingredients. After turning off the heat, let the soup sit covered for 5 minutes to allow the flavors to fully meld, then serve.

Drinking Tips

1. It is recommended to consume 2–3 times per week, with one continuous month of consumption constituting one regulation cycle. Excessive consumption should be avoided, especially for individuals with normal thyroid function, as excessive iodine intake may lead to thyroid dysfunction. Moderation is the key to health preservation.

2. This medicinal food should ideally be consumed warm during the lunchtime period, when the body’s yang qi is most vigorous and the spleen and stomach’s transformative and transportive functions are at their peak, thereby maximizing absorption of its active components. It is not advisable to drink it in large amounts in the evening, as this may increase the burden on the kidneys or lead to frequent nocturia, thereby affecting sleep quality.

3. While consuming this medicinal diet, it is recommended to incorporate ingredients that soothe the Liver and regulate Qi, such as adding a small amount of Citri Reticulatae Pericarpium (tangerine peel) or Rosae Rugosae Flos (rose flower) to the decoction, which can enhance its effects of relieving Liver depression, resolving Phlegm, and dissipating masses. At the same time, maintaining a calm emotional state and avoiding staying up late will yield more significant therapeutic results.