Yang Is in Its Final Retreat
Hánlù 寒露, Cold Dew, arrives around October 8 and is the fifth of Autumn's six Qi Nodes. It follows Qiūfēn 秋分 (Autumn Equinox) by about two weeks and precedes Shuāngjiàng 霜降 (Frost Descends), and its name records a specific observation: the dew that settles overnight has turned cold to the touch, and in colder places it now sits a few degrees short of frost. Daylight at the latitude of most of the continental United States is down to roughly eleven and a half hours and is still shrinking by two to three minutes a day, close to the fastest rate of the year. Overnight lows in many inland regions dip toward freezing, deciduous trees move from turning color to dropping leaves, and the air starts to feel different in the nose and throat. Cold air holds far less water vapor than warm air, and the first evenings with the heat on dry the indoor air further.
The older Chinese calendar divides each Qi Node into three five-day periods, each named for something an observer in northern China could watch for. Hánlù opens with hóngyàn lái bīn 鴻雁來賓, the wild geese arriving as guests, and closes with jú yǒu huáng huá 菊有黃華, the chrysanthemums putting out yellow flowers. Both still hold for much of North America, where migrating geese fill the flyways in October and garden chrysanthemums are among the last plants in bloom.
If you have been following the Qi Node series, you will recognize Hánlù as the first node with cold in its name. Lìqiū 立秋 (Autumn Begins) opened the season in early August while the weather was still hot, and the nodes since have tracked the heat breaking, the first dew forming, and the equinox. Since the equinox, nights have been longer than days, and Yīn qì has held the larger share of the cycle. Yáng qì, which reached its outward peak at the Summer solstice, continues to withdraw toward the interior of the body and the depth of the year, and it reaches its lowest point at Dōngzhì 冬至 (Winter Solstice) in December. Hánlù is where the weather and the calendar agree that Autumn has passed its midpoint.
Metal, the Lung, and Dry Air
Autumn belongs to the Metal phase. Metal describes movement that contracts, descends, and settles, the reverse of the upward and outward spread of Summer's Fire. In the landscape it shows up as harvest and as plants drawing their resources down and in. Before a deciduous tree drops its leaves, it pulls nitrogen and other nutrients back out of them and stores them in its wood and roots for Winter. In Chinese medicine, Metal governs the Lung and its paired organ, the Large Intestine, and its climatic qì is dryness, zào 燥.
The Lung carries a wider role in Chinese medicine than its biomedical counterpart. It governs respiration and the distribution of qì through the body, it controls the skin and the opening and closing of the pores, it opens into the nose, and it governs wèi qì 衛氣, the defensive qì that circulates at the body's surface and meets cold and wind first. Classical writers called the Lung the delicate organ, jiāozàng 嬌臟, because it sits highest in the torso and is exposed to the outside air with every breath. It is said to favor moisture and to be injured by dryness, and the Autumn complaints we see in the clinic follow that description closely: a dry or scratchy throat, a tickling dry cough, chapped lips and cracked knuckles, and, on the Large Intestine side of the same system, dry and difficult stools. People who catch every cold that goes around in October have often come out of Summer with a Lung system that was already depleted.
Biomedicine describes a closely related picture. The airways keep themselves clean with a thin layer of mucus that traps particles and microbes, and with cilia that sweep that layer up and out. Cold, dry air thins the layer and slows the sweeping, which appears to be part of why respiratory infections climb as Autumn deepens. Cold also shifts circulation. As the skin cools, blood vessels near the surface constrict, sweating drops off, and more blood volume is held in the core, which the kidneys partly offset by producing more urine. Chinese medicine describes the same movement as fluids and Yáng drawing inward from the exterior. Both descriptions lead to the same practical conclusion: in Autumn the body's surface is drier and less defended than it was in Summer, and protecting it takes more deliberate attention.
What the Season Asks of Us
The Sùwèn 素問, the first half of the Huángdì Nèijīng 黃帝內經 (compiled circa 100 BCE to 100 CE), sets out its Autumn guidance in its second chapter. It advises going to bed early and rising early, with the rooster, keeping the mind settled, and gathering attention and qì inward so that Lung qì stays clear. It calls this the way of nurturing the gathering, yǎng shōu zhī dào 養收之道, and it warns that neglecting it injures the Lung and sets up digestive trouble in Winter. A farming household in Autumn stops planting and starts storing, and the text asks the body to make the same shift by spending less outward and consolidating more.
The emotion associated with Metal is grief. The Sùwèn's discussion of the emotions says that grief causes qì to dissipate, and grief that has gone on for a long time often shows clinically in the Lung as shallow breathing, a quiet voice, heaviness in the chest, and a tendency to catch colds. Metal's function in the body is release, through the exhale of the Lung and the elimination of the Large Intestine, and grief belongs to the same movement as the work of letting go of what has ended. Hánlù suits that work in practical form. It is a good point to finish the projects Summer started, to close commitments that have run their course, and to clear room before Winter, the season in which the tradition asks for the most rest.
Living with Hánlù
The recommendations below follow the four categories used throughout the Qi Node series.
Eat with the season
Shift meals toward cooked, warm food, and favor foods that moisten. Pears, apples, and persimmons are in season and have a long history in Chinese seasonal eating for dry throats and dry coughs. A pear baked or poached with a spoonful of honey is the classic preparation, and honey appears to ease cough in its own right. Oats, sweet potatoes and winter squash, mushrooms, sesame seeds and almonds, and soups and stews built on broth all suit the season. Raw salads still have a place, ideally alongside something warm in the same meal as the nights get colder.
Seasonal dietetics since Sūn Sīmiǎo 孫思邈 (circa 652 CE) has advised reducing pungent flavor and increasing sour in Autumn. Pungent flavors disperse outward and dry, while sour gathers and contracts in the same direction as the season. In practice that means going easier on hot peppers, raw onion and garlic, and heavy coffee and alcohol, all of which dry, and adding sour through lemon, vinegar in dressings, and tart apples.
Move with the season
Reverse Summer's timing. Mornings are now cold and damp, so move exercise later in the morning or to midday, once the air has warmed. Brisk walking, hiking, cycling, and slower practices like tàijíquán 太極拳 and qìgōng 氣功 all suit a season that favors steady effort over peak output.
Finish a workout dry and covered. In Chinese medicine, sweat cooling on the skin in a cold wind is the classic route by which cold enters through open pores, and in physiological terms wet clothing in cold air draws heat from the body much faster than dry clothing does. On cold mornings, cover the neck and upper back, which meet the wind first.
Rest with the season
Follow the Sùwèn's advice and move bedtime earlier as the nights lengthen. Rising early matters as much, because morning light is what anchors the body clock as the days shorten. Getting outside within an hour of waking, even under cloud, gives the circadian system a far stronger signal than indoor light, and the same exposure appears to help with the low mood many people notice as Autumn advances. Once the heat comes on, a bedroom humidifier holding relative humidity around 40 to 50 percent protects the nose and throat overnight.
Tend your Lungs
The cultivation practice for Hánlù is the breath. Spend ten minutes a day breathing slowly through the nose at about six breaths a minute, letting each exhale run longer than the inhale. In Chinese medicine the Lung governs descent and release, and an unhurried exhale practices both directly. In physiological terms, slow breathing at that rate raises vagal tone and shifts the nervous system toward its parasympathetic state, which slows the heart and settles the body toward rest.
Hánlù is also a good time to give grief its due. If the year has carried a loss, Autumn is when it tends to surface, and setting time aside for it, through a visit, a letter, or a quiet afternoon, keeps it from settling into the chest. Watch for a dry cough that lingers past two or three weeks, or low mood that deepens as the light shortens instead of easing with rest and morning sun. Either deserves a proper evaluation.
Hánlù sits past the middle of Autumn. Shuāngjiàng follows around October 23, and Lìdōng 立冬 (Winter Begins) arrives in early November. The Sùwèn ties Autumn's habits directly to Winter's health, and what you settle now in sleep, food, and attention to the breath is what the body carries into the coldest months.