The Dao of Longevity - Seasonal Harmonization for Summer

Henry McCann, DAOM, LAc, Dipl OM

One of the most important teachings of Chinese medicine is that there is a seamless continuum between the body and the environment around us. The Zhi Zhen Yao Da Lun (Great Treatise on the Essentials of the Most Reliable, Su Wen Chapter 74) says, “Heaven and Earth are the great principle, man’s shen-spirit penetrates and reflects them.” (天地之大紀，人神之通應也) There are two vitally important words in this sentence. First is the word tong 通 or “penetrate.” This word implies a movement through something, but also an intercourse with. In the Shuo Wen Jie Zi, the Han Dynasty dictionary that gives detailed explanations of the images of Chinese characters, the definition of tong is “da,” to extend or reach to something (通：達也), and the definition of “da” is to move without encountering resistance. (達：行不相遇也) Thus tong means some sort of unimpeded connection with something. In the context of Chinese medicine this connection is with the natural world around us.

The second important word in this sentence is ying 應 or “reflect.” The definition of ying is “dang,” to match equally (應：當也). This makes our original quote from the Su Wen become quite deep in meaning. According to the ancient observer, that which is eternal and constant is the cycling of the natural world around us, both here on earth and in the heavens above. Humans were created as small microsystems of this greater natural world. Not only are we in constant intercourse with nature around us, we are actually miniature versions of it. Humans match and are equal to the structure of the natural world. Chinese medicine’s most basic and fundamental theory is that if we stay in harmony with things around us, we will enjoy and long and healthy life.

In a previous article we looked at this idea through the lens of harmonizing the body with Spring. The next and current season is Summer, and as the weather around us changes, so should we to continue living as best as possible in harmony with our surrounding environment.

Yin, Yang and the Five Phases of Summer

All cycles are manifestations of the movement of Yin 陰 and Yang 陽, and the seasons are no different. Both Spring and Summer are Yang seasons. Yang represents growth, expansion and outward movement. Certainly, this time of year plants are in active bloom and the weather is warm and sunny. Spring starts this movement of growth, and then Summer takes over to allow growth to mature to its fullest extent. Thus, Spring is the Lesser Yang (Shao Yang 少陽), the earlier stages of expansion and growth, while Summer is the Greater Yang (Tai Yang 太陽), the culmination of expansive movement in nature.

In Five Phase Theory (五行理論) this Greater Yang movement is called “Fire.” In addition to the Summer season, Fire is associated with the time of high noon. Fire represents heat and the color red. In the body Fire is the Heart among the Zang-viscera, and the Small Intestine among the Fu-bowels. By extension from these internal organs, Fire also represents the blood vessels, the tongue, and the function of speech and communication. The taste of Fire is bitter, its associated grain is sorghum, and the domestic animal is the sheep. The Confucian tradition speaks of the Five Constant Virtues (五常), and the virtue associated with Fire is sacred ritual connection – Li (禮).

In the Huang Di Nei Jing (or Neijing for short) there is a famous 8 character statement that says 春生, 夏長, 秋收, 冬藏 – “Spring gives birth, Summer grows, Autumn harvests and Winter stores.” Fire represents this pinnacle of outward expansion that is Summer, and thus in this sentence is called “growth.”  The Neijing also says 春夏養陽, 秋冬養陰 – “in Spring and Summer nourish Yang, and in Autumn and Winter nourish Yin.” During Summer we stay healthy by trying to mimic this Fire/Yang movement of nature, but we need to be cautious to do so just right. Both too little and too much divert us from health.

The Neijing on Summer

As mentioned in our previous issue on Spring, the second chapter of the Su Wen section of the Neijing is titled The Great Treatise on Regulating the Spirit with the Four Seasons (四氣調神大論). This chapter gives basic descriptions of the four seasons and how we should specifically move with them, based of course on Yin-Yang and Five Phase theories. The section of this chapter that discusses Summer begins by saying, “the three months of Summer denote opulence and blossoming. The qi and heaven and earth interact and the myriad beings bloom and bear fruit.” This basic statement defines the season as the Fire phase and Greater Yang. The commentary on this sentence by Tang Dynasty physician Wang Bing says, “the generation of yang begins with Spring. When it comes to Summer, the [yang] abounds and all beings grow.” (Unschuld, pg. 46)

The chapter continues with, “go to rest late at night and rise early. Never get enough of the sun.” The days of Summer are longer than that of all the other seasons. This is, again, because Summer is the greatest Yang of all the seasons. Certainly, sleep and rest are important keys to health. However, the active nature of Summer means that we should also be more active. Summer is the time to be outside in the sun, and to be more physically active. It is the time of year that we can get away with less sleep (still remembering to always strike a balance based on our individual levels of health). Since the weather is good, Summer is also the natural time for vacation and travel.

This passage in the Su Wen also gives advice on our mind states. It continues, “let the mind have no anger, and things will blossom beautifully.” Anger is a violent movement of qi upwards and outwards. In Chinese medicine it causes the Liver to upsurge, which can result in an abundance of heat that has potential to damage the Heart. This sentence really represents is what happens when there is too much expansion and growth. The word for “Chinese medicine” in Mandarin is Zhong Yi 中醫. The word Zhong 中 refers to the nation of China, Zhong Guo 中國. However, the word Zhong really means “center.” So, Chinese medicine, Zhong Yi, is literally “medicine of the center.” Summer is the time to encourage growth and expansion, but too much is as bad as too little.

According to the Neijing these practical guidelines bring us into resonance with Summer and allows us to nourish this ideal of grown and expansion. If we fail to harmonize with the season, the Neijing admonishes us that we will suffer disease in the Fall and Winter to follow.

Summerheat – The Pathogen of Summer

Chinese medicine recognizes three basic categories of causes of disease known as the Three Causes (san yin 三因) – internal causes, external causes, and neither internal nor external causes. Internal causes are the Seven Affects (七情), which are joy, anger, worry, over thinking, sorrow, fear and fright. External causes are the Six Excesses (liu yin 六淫), namely wind, cold, heat, summerheat, dampness and dryness. Neither internal or external causes (bu nei wai yin 不內外因) include just about everything else that can be imagined, such as diet, parasites, living environment, injuries, insect bites and drowning.

Summerheat (shu 暑) is only contracted in Summer. Thus, Summer is unique in Chinese medicine in that it is the only season that has a cause of disease specific to it. Summerheat exemplifies what happens when there is an overabundance in one direction of a specific weather pattern and how it can affect health negatively. Certainly, heat by itself is good in the proper amount and proper time. However, sometimes in Summer the weather is hot enough to cause disease.

Chinese medicine distinguishes between two variations of Summerheat: Summerheat-heat (shu re 暑熱) and Summerheat-damp (shu shi 暑濕). Summerheat-heat is also called Summerheat-stroke (zhong shu 中暑) and basically refers to what in medicine is called heatstroke from exposure to hot weather. Heatstroke happens when body temperature reaches 40 degrees Celcius (104 F) or higher. This condition manifests additionally with confusion, lack of sweating, difficulty breathing, fatigue, muscle cramps and possibly fainting. First aid for heatstroke includes moving to a shady cool area and applying ice or cold compresses to the head, neck, armpits or groin.

Summerheat-damp is a variety of Summerheat with more signs and symptoms of dampness, although this still corresponds to a type of heatstroke in western medicine. Summerheat-damp signs and symptoms include nausea or vomiting, poor appetite, stuffy chest, heavy or fatigued limbs, and possibly diarrhea. Vomiting and diarrhea are especially dangerous since they can easily lead to dehydration, which can be a medical emergency.

In extremely hot Summer weather it is important to dress lightly and be cautious about physical overexertion. Drinking fluids to stay hydrated is essential. Some people are at a higher risk for developing heatstroke, such as the elderly or the very young, or patients on certain medications such as diuretics. In all cases when symptoms of heatstroke begin, seek medical attention.

Eating for Summer

There are two basic approaches to eating, a preventive approach that harmonizes the body with the basic Yang nature of Summer, and a remedial approach that cools the body when there is over exposure to that Yang/heat. The basic preventive diet for Summer is one that everyone can follow. In general food choices should include local and seasonal vegetables and fruit, trying to include as many colors as possible to represent all of the Five Phases. Since Summer is the season of utmost Yang, and Yang by nature is light and floating, diet should be lighter than in other seasons. In general meals should include only the minimum of salt since salt by nature is condensing and descending (i.e., the opposite of Summer). Even though Summer is the time of heat, it is appropriate to use a small amount of mildly spicy food. Spicy flavors induce an upward and outward movement of qi in the body, and therefore mimic the movement of Summer. Mildly spicy foods also induce gentle perspiration to clear heat from the surface of the body. Thus a small amount is warranted. However, too much spicy food moves the body into an overly heated state and should therefore be avoided.

Even though it may sound counterintuitive, Chinese medicine recommends sipping hot liquids during Summer. The very nature of cold is to congeal and contract. This Yin movement is also the opposite of the Summer season. Consuming cold foods over time damages Spleen and Stomach function, and will lead to the accumulation of dampness internally. As previously mentioned, damp combines with Summerheat to be one of the major pathologies associated with hotter weather. Sipping warm beverages allows the body to stay hydrated while inducing mild perspiration along the lines of eating mildly spicy foods. To better balance warm beverages with hot weather, it is very appropriate to drink mildly cooling herbs or teas (in Chinese medicine a food or drink can have a “cooling” nature even though it is taken at a warm temperature). With teas, in general, green teas are mildly cooling in nature while dark teas (such as oolong, pu erh, or black teas) are mildly warming. One very famous green tea that is revered in China for Summer consumption is Long Jing Cha 龍井茶, or Dragon Well Tea.

This idea leads into the next type of diet for Summer – the consumption of foods that are mildly cooling. Especially when heat is intense, or when people are exhibiting signs of overexposure to Summerheat, one effective diet strategy is to include foods of a moistening and cooling nature. Most vegetables have a mildly cooling nature, another reason why their consumption is important in Summer. Foods to consider adding on a daily basis include all sorts of sprouts (e.g., mung bean or alfalfa), cucumbers, muskmelon, winter melon, tomato, and loofah. All of these have a mildly heat clearing and gently moistening effect. In-season fruits such as plums and peaches are also heat clearing and moistening. Plums in particular have a slightly sour nature so they benefit the fluids at a time when too much sweating can damage them.

Mung beans (lü dou 綠豆) are an important remedy specifically for Summerheat. These small green beans (the name in Chinese literally means “green bean”) cool and detoxify the body, and are traditionally used as an antidote for different types of poisoning. They can be cooked into soups or congees to help the body adapt to extreme heat, and in China they are even made into sweet dessert soups. Another very famous food remedy specifically for Summerheat is watermelon. In Chinese herbal circles, watermelon’s nickname is “Natural White Tiger Decoction,” named after a famous formula for clearing internal heat (Bai Hu Tang 白虎湯). Watermelon can be eaten fresh or can be juiced.

In addition to the actual foods eaten, the method of cooking should also be adjusted for the season. Preferentially foods should be prepared using relatively light and quick methods, in other words cooking techniques that mimic the light and fast nature of Yang. Vegetables can be sautéed at high heat for short periods of time, or can be parboiled or steamed. Cooking methods should include more water and less heavy oil. Fruit can be served lightly chilled in the warmest of weather, but still be careful to avoid consuming large quantities of iced foods or beverages.

The foods and cooking methods to avoid are all ones that overly constrict the movement of qi. For example, very greasy or oily foods create stagnation and dampness, and thus are opposite to the Yang movement of Summer. These foods also damage the digestive function. Overly sweet foods also create dampness, and, as already mentioned, very salty foods create a Yin inward movement of the qi.

Scroll down to the end of this article for seasonal recipes to try at home!

Herbs for Summerheat

In addition to the Dragon Well Tea mentioned above, there are many herbs that can be consumed to counteract the effects of Summerheat. One of the easiest to get in the west as a tea is peppermint (bo he 薄荷). Peppermint is a commonly used Chinese herb that has a mildly heat clearing effect. It also specifically clears Summerheat. To make peppermint tea simply steep dried or fresh leaves in boiling hot water. Although the leaves can be steeped in boiling hot water, be careful not to actually put the leaves in boiling water that is left on a flame to continue boiling (in other words the leaf should be steeped, not decocted). Prolonged cooking of peppermint evaporates the essential oils in the plant that are beneficial.

Another common herbal tea for Summer is chrysanthemum (ju hua 菊花). Chrysanthemum is mildly cooling and sweet in nature and thus both clears heat as well as protects fluids. It is especially useful when the Liver channel is overheated resulting in irritability, blurry vision, headache or red eyes. In Summer it can be taken as a daily beverage. Like peppermint, the flowers can be directly steeped in boiling hot water but need not be decocted.

Other teas that are mildly heat clearing for use in Summer are chamomile (a western herb) and lotus leaf (he ye 荷葉). Another excellent herbal tea for Summer, although hard to find in the west, is called Zhu Ye Qing 竹葉青. This tea was a special product developed by the Buddhist monks of Mount Emei in Sichuan province, China. In the 1960s it was first given to an outsider and after that became popular. For those who can find it, Zhu Ye Qing is heat clearing and spirit calming, and can be taken as a daily beverage. What all these teas have in common is that, unlike Dragon Well, which is a true tea plant, they are all caffeine free.

Acupressure and Patting for Summer

In the previous article on Spring we discussed patting or beating at acupuncture points or along channels, a technique know as Pai Da (拍打) that is an important method of health preservation in both Chinese medicine and Qigong circles. In acupuncture theory one of the best channels to clear heat is the Yang Ming 陽明 channel. Yang Ming means “Yang brightness” and in the body refers to the Large Intestine channel on the arm and the Stomach channel on the leg (see diagrams). These channels are said to be full of both qi and blood, and clinically both Yang Ming channels are effective for treating conditions of repletion heat. In fact, most of the very important heat-resolving acupuncture points are found on either the Stomach or Large Intestine channels.

One of the best points for clearing heat is Qu Chi 曲池穴, the eleventh point of the Large Intestine channel (LI-11). This point is located at the end of the crease of the elbow on the outside of the arm when the arm is bent (see diagram). Qu Chi is used to treat all sorts of heat conditions including high fever, sore throat, redness of the eyes, agitation, manic behavior, and red inflamed skin. In modern times it is used to treat some types of hypertension. In addition to clearing heat, Qu Chi opens the movement of qi and blood in the upper limbs to treat numbness and pain.

There are a few different ways to stimulate this point and channel that are appropriate for general use in Summer. First, Qu Chi by itself can be treated with acupressure. Using the thumb press deeply into the point until there is a heavy or numb sensation that moves slightly down the arm. Hold pressure for a count of 30 seconds and then release. Repeat several times throughout the day. Alternately, use an acupressure device to do the same procedure.

In addition to acupressure at Qu Chi, Pai Da is done at this point. With an open hand slap the area of Qu Chi with moderate intensity. At the beginning the technique should start more gently which is known as Wen Pai (文拍; Scholar Patting), and then progress to stronger stimulation known as Wu Pai (武拍; Military Patting). Alternate pats on the right and left sides of the body, continuing for 5 to 10 minutes (or longer). While patting, the skin of the arm will turn red. In Chinese medical terms patting draws the Yang qi to the surface of the body area being stimulated. By doing so it can help the body clear heat that may build up during Summer, especially when done along the Yang Ming channel which functions to clear heat.

Instead of applying Pai Da only at Qu Chi, the entire Large Intestine channel can be stimulated. Start at the outside of the shoulder patting downward along the arm finishing up at the He Gu 合谷穴 LI-4 area of the hand (the area between the thumb and first finger). Patting in this direction is moving against the normal flow of the channel. Thus, it is a method of drainage and is more effective at clearing heat than patting starting at the hand moving towards the shoulder. Please remember that Pai Da should not be done over areas of wounds or fractures, by pregnant women, or by patients with cancer. In general it is best to do Pai Da under the supervision of a doctor of Chinese medicine or an experienced Qigong teacher.

Heat Treatment During Summer

While most of this article so far focuses on how to clear extra heat from the body in the Summer, there is a special treatment method that actually uses heat during the very hottest period of Summer. Starting in the Qing Dynasty (1644 – 1912) there has been a method of treating long standing cold disease by employing a type of moxibustion on the three hottest days of summer. These days are called the San Fu Tian 三伏天, and the method of treatment San Fu Moxibustion, or San Fu Jiu 三伏灸.

San Fu Moxibustion was originally used to treat chronic respiratory problems such as asthma, although in modern times it has been expanded to other conditions. The basic theory of San Fu treatment combines the effective use of hot herbs applied to acupuncture points on the body during the hottest (i.e., most Yang) days of Summer. Doing so very aggressively expels cold that may linger in the body. Obviously however, this treatment is designed for patients who are vacuous and cold, and should not be performed on patients that in general have hot conditions.

The actual treatment days are chosen based on Chinese astrology. The first of the San Fu days is the third geng (Yang metal) day after Summer Solstice in the Chinese calendar. The second day is 10 days after the first, and the third day is the first geng day after the Beginning of Autumn (which falls at the beginning of August in traditional Chinese calendars). Usually there are three days in this method of day selection, but occasionally there is a fourth that can be used. For example, in 2017 the San Fu days are July 12, July 22, August 1, and August 11. Around noon on these days (noon is a Yang time) a special paste is applied to acupuncture points on the upper back that all warm the Yang qi and expel cold. While recipes for this paste vary, they include very hot herbs such as mustard seed (bai jie zi 白芥子), asarum (xi xin 細辛) and ginger juice.  Pastes with mustard are very irritating and cause a heating reaction on the skin, and if left for too long a period of time they can even create a chemical burn. Therefore, San Fu Moxibustion should only be performed by a licensed practitioner of acupuncture or Oriental medicine who is familiar with the technique and its application.

In Korea there is a traditional custom of eating ginseng and chicken soup on these same San Fu days, and this dietary remedy can be done by anyone at home. Ginseng and chicken soup has a very nourishing and supplementing function, and eating it on the San Fu days can help build internal Yang qi to prevent disease in the colder seasons that follow. This is very useful for patients who generally have weak qi, especially of the Spleen or Lung. Patients who are very hot by nature should avoid eating this soup in the summer.

Yang Expands, then Yin Begins

Yin and Yang are constantly in a state of mutual transformation. In other words, when something reaches its zenith, it naturally transforms into its opposite. When Yang peaks, it then turns to Yin and vice versa. We all see this on a daily basis in the cycling between day and night. During the course of the year this happens as warm weather turns to cold and cold then turns back to warm.

Even though Summer is a Yang season, because Summer is the maximum expansion of Yang it is also the time that Yin is born. In the Chinese calendar the peak of Summer is the Summer Solstice (xia zhi 夏至), which this year falls on June 21. Up until June 21 the days continue to get longer and longer. However starting the very next day after June 21, each day the length of light shortens. This shortening of the light is the gradual diminution of Yang in the natural world to make way for the Yin time of year. Thus the Lü Shi Chun Qiu (The Spring and Autumn Annals of Lü Bowei; 呂氏春秋), the classic text of Chinese philosophy from the 3rd century BCE, says that during Summer, “the enlightened person fasts and observes vigils, makes sure to stay deep inside his house, and keeps his body utterly still… He settles the qi of his Heart, maintains stillness in his inner organs, and engages in no rash undertaking. He does all these things in order to assure the completion of the first traces of Yin.”

In this season of Yang and movement it is therefore advisable to still take time for quiet and for reflection. Once Yang peaks, the next movement is one of contraction and storage. This is a particularly urgent recommendation for those of us living in this modern fast paced world. We all constantly strive to be in a Yang state of younger, faster, louder. And certainly during Summer this seems appropriate. But in the middle of Yang is this nascent Yin that also needs attending. This is the reminder that we, as a method of preserving our health and longevity, should all take time to smell the roses. After all, they bloom in Summer.

Recipes

Licorice and Mung Bean Congee - Gan Cao Lü Dou Zhou 甘草 綠豆粥

Ingredients:

• Rice 150g
• Licorice (gan cao 甘草) 50g
• Mung Bean (lü dou 綠豆) 50g
• Rock sugar

Directions:

1. Place licorice in 1850ml (just under 8 cups) of water. Let soak for about 10 minutes then bring to a rapid boil on high flame. Once boiling reduce to a medium flame and simmer for about 15 minutes or until the water becomes yellow. Strain out the licorice slices.
2. Put mung beans into the water from step 1 above, and bring back to a boil. After boiling, reduce to a low flame and simmer for about 40 minutes until beans are soft.
3. Add in rice and continue simmering for about 30 minutes until the rice is staring to break apart and the entire mixture has a soft soupy consistency. Add in rock sugar to taste.

This recipe aromatically opens the Stomach, strengthens the Spleen to transform dampness, and clears heat and drains damp. It is appropriate for most people in the heat of Summer, but should be avoided by those with very cold and weak Spleens, or people with diarrhea from weak Spleen and Stomach.

In this recipe mung beans clear heat and eliminate Summerheat-damp. Licorice is mildly cooling and supplements the Spleen and Stomach. The sweet flavor helps nourish fluids and the bland nature of the rice cooked into congee eliminates dampness. The licorice used in this recipe is the licorice root used in Chinese herbal medicine, and can be purchased dried and sliced at any Chinese herbal pharmacy.

Purslane Mediterranean Salad

Purslane is a culinary herb that is only available fresh in Summer. It has a mildly sour but very refreshing taste and can be used as both a food and a medicine. In Chinese, purslane is called Ma Chi Xian 馬齒莧 and is an herb that is known to clear heat and eliminates heat toxins. It is used internally to treat dysentery and topically to treat pain and swelling from toxic insect or snakebites. Modern research has shown that purslane is useful in treating shigellosis, also known as bacillary dysentery.

In addition to its use in medicine, purslane is a commonly eaten plant in areas such as the Mediterranean. A delicious salad can be made out of cucumber, tomato, purslane and other greens. First, chop the cucumber and tomato into small chunks or cubes. Mix in fresh mesclun salad greens and coarsely chopped fresh purslane. Dress with a small amount of olive oil, vinegar, and freshly ground black pepper.

This recipe uses fresh seasonal vegetables. All the vegetable ingredients are mildly cooling and help moisten and protect fluids without creating dampness. The purslane and vinegar are both slightly sour, which also protects fluids that have been damaged from heat or over sweating. The black pepper is a mildly Yang warming food to counterbalance the sour and cooling aspect of the rest of the salad. This dish is a fantastic addition to a larger meal, or can be eaten as a light meal by itself. Bon appétit!

Korean Ginseng and Chicken Soup - Samgyetang 삼계탕

Ingredients:

• 1 small chicken (Cornish game hen)
• ¼ cup glutinous rice
• 1 – 2 small fresh ginseng roots (ren shen 人參)
• Several Chinese dried red dates (hong zao 紅棗)
• Several peeled garlic cloves

Directions:

1. Soak rice in a small amount of water for 1 hour
2. Clean and rinse chicken and then stuff the cavity with the rice, ginseng, red dates and garlic. Place in pot and cover with water.
3. Bring pot to a rapid boil and then continue boiling over high heat for about 20 minutes, skimming off the foam as necessary. Replenish water that has boiled off and then continue to simmer for another 40 minutes until chicken is falling apart or can easily be pulled apart.
4. Garnish with freshly chopped scallions, salt and pepper to taste.

This is a traditional Korean dish to be served during the hottest days of summer, known in Chinese as the San Fu Tian 三伏天. Eating this very nourishing soup during this time strongly supplements the Yang qi internally to stave off disease that may arise in the colder seasons. People with internal heat conditions should avoid this soup or eat only a small amount.

References

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