Pathogenic wind is characterized by ascending, dispersing, upward, and outward movement. The head, face, and skin are the most vulnerable to invasion by pathogenic wind, making it the most damaging external pathogen in cosmetology. Manifestations of pathogenic wind invading the exterior include a skin rash that comes and goes, appears as wheals or milium, and gathers at the head, face, or all over the body. Other symptoms include itching skin, pigmentation, depigmentation, hordeolums, rosacea, swollen lips,and deviated eyes and mouth. Symptoms can be complicated by other external pathogens.Pathogenic wind-cold invasion leads to qi stagnation and blood stasis, causing chilblains or pale, white, or dark purple skin lesions. When pathogenic wind-dampness accumulates on the skin, blister, erosion, or fluid tissue exudation appear. Pathogenic wind-heat causes red, hot skin lesions.

Internal wind is mostly caused by dryness producing wind due to prolonged yin deficiency, blood deficiency, blood stasis, or blood heat, causing dysfunction of the zangfu organs. Manifestations include a prolonged course of disease, dry and dim skin with desquamation, hypertrophy, itching, or dry hair.

The prolonged invasion of either external or internal wind leads to dryness, loss of resiliency, and wrinkles due to qi and blood disharmony and malnourished skin.

Diseases due to external cold mainly occur in winter. The head, face, and limbs are the most vulnerable, as these areas are the most exposed. The nature of cold is to contract, so invasion of cold always leads to contraction of the pores, causing dysfunctional secretions of sweat and sebum. This leaves the skin without moisture, so dryness, desquamation, and cracking occur. Cold is also congealing. Thus the invasion of pathogenic cold leads to qi stagnation and blood stasis, causing the slow movement of qi and blood and pale or dark purple skin or lips. In serious cases the movement will stop, causing sores or ulcers.

Internal cold is mostly caused by yang deficiency of kidney and spleen, and manifests as loss of vigor, mental fatigue, lack of strength, aversion to cold, and low functioning of the zang-fu organs. Internal cold invading the exterior leads to low functioning of the skin, causing dim or pale skin due to disharmony between qi and blood. The consequence is premature aging of the skin, accompanied by dry hair and hair loss.

The prolonged invasion of either internal or external cold influences the vigor of the local tissue and the whole body, leading to loss of beauty and charm.

Pathogenic summer heat is always combined with dampness. Pathogenic heat can lead to excessive sweating by opening and discharging the striae and interstitial spaces,damaging the fluids, consuming qi, and allowing heat toxins to accumulate on the skin.As a result, prickly heat, acne, or furuncles appear. When the fluids are damaged and qi is consumed, mental fatigue and lack of strength occur.

As there is no internal heat, and the damage of external heat is seasonal, the damage by pathogenic summer heat is relatively minor.

Pathogenic dampness is viscous and stagnant, causing stickiness and turbidity in the affected areas. External dampness always amasses on the skin accompanied by pathogenic wind, leading to blisters, festering, tissue fluid exudation, damp itching, or greasy skin,and a dirty complexion with profuse eye gum. Invasion of pathogenic dampness is a long course of disease.

Internal heat is mainly caused by the spleen failing to transform and transport, and the stagnation of phlegm-dampness. Accumulation of internal dampness can cause obesity,and a swollen face and lower limbs. If dampness transforms into heat and steams upward,greasy dirty skin, dark circles under the eyes, black spots, bad breath, and dirty teeth will occur. The manifestations of internal dampness steaming outward to the skin are the same as those caused by external dampness amassment.

Clinically, internal and external heat are always combined. The damage to skin and physical beauty by both internal and external dampness is prolonged, and may increase the psychological burden of the patient.

External dryness prevents the skin and hair from being moistened, causing dryness,roughness, scales, cracks, and wrinkles on the skin, as well as dry hair and hair loss.Internal dryness is mainly caused by prolonged yin deficiency, blood deficiency, or blood stasis, leading to dryness of the mouth, throat, and eyes, and dry bound stool. When internal dryness invades outward to the skin, the manifestations are the same as invasion of external dryness.

Both internal and external dryness may lead to premature aging of the skin and hair due to malnutrition.

Pathogenic fire flares up and damages yin, and is one of the most damaging factors for the appearance. External fire is always accompanied by pathogenic wind, causing yang heat pathological changes on the head and face, manifesting as red face or eyes, erythema,pimples, pustules, sores, deep-rooted boils, and whitlow. The lesions may appear on the whole body when the skin is invaded.

Internal heat is caused by dysfunctional zang-fu organs, uncontrolled emotions,accumulated qi, blood, phlegm, and rheum, excessive intake of warm or spicy food, or innate yang exuberance. Deficient yin failing to restrict yang can also cause internal heat.Manifestations of internal heat include fever, vexation, dry mouth, dry stool, and dark urine.

When internal fire accumulates on the skin, the pathological changes are the same as those caused by external fire invasion.

Most diseases caused by external fire, and some diseases caused by internal fire,are acute with obvious redness, swelling, heat and pain. Such diseases are easily cured.Only diseases caused by internal heat due to yin deficiency are chronic. Both internal and external heat can damage the fluids and consume yin, preventing moisture and nourishment from reaching the skin and hair. Dryness, roughness, cracking, wrinkles, dry hair, hair loss, and an emaciated body ensue.

The seven emotions are human reactions to the objective world, which are normal mental activities, and do not cause disease. When some sudden, strong, lasting mental stimulation, exceeding the scope of normal physiological activities occurs, dysfunctional qi and blood in the zang-fu organs and qi counterflow appear, causing disease. Many cosmetic conditions are related to mental stimulation or excessive emotions.

The heart governs the blood and vessels and is responsible for storing the spirit. The liver governs the free flow of qi and is responsible for storing blood. The spleen governs transportation and transformation and is the origin of the production of qi and blood.Diseases due to the seven emotions are mostly caused by damage to the heart, liver, or spleen, and disharmony between qi and blood. Excessive thought damages the heart and spleen, and causes deficiency of qi and blood, leading to premature aging, wrinkles, a haggard look, and a pale or sallow yellow complexion. Prolonged depression may cause the liver to fail to govern the free flow of qi, leading to a gray or blackish complexion,spiritless eyes, pale nails, facial spasms, and hair loss.

Being excessively hungry or full can cause disease. Being excessively hungry may lead to deficiency of qi and blood due to lack of resources, causing an emaciated body, pale complexion, dry dim skin, and dry hair. Being excessively full increases the burden on the spleen and stomach, influencing the function of digestion, absorption, and transformation, and causing many diseases. Many cosmetic conditions are the result of spleen and stomach disease, such as acne, blackish facial patches, and obesity.

Indulging in the unbefitting diet, such as eating too hot or too cold, or indulging in one of the five flavors, may lead to disharmony between yin and yang. Cosmetic conditions may also be caused by lack of nutrition. Acne is caused by pathogenic fire due to excessive fried food. Many diseases are caused by damaged yang qi in the spleen and stomach due to excessively cold food. Excessively stimulating food causes allergic diseases. Obesity is caused by excessive rich food.

Prolonged overwork and use of physical strength damages qi and leads to weakness due to qi deficiency, mental fatigue, and an emaciated body. Excessive mental labor damages the heart and spleen, leading to lack of spirit and forgetfulness, a sallow yellow complexion,and functional disorders of the intestine and stomach. Indulging in too much sexual activity may damage the kidney essence, causing mental fatigue, a haggard look, a dim complexion,black spots on the face, dark circles under the eyes, and white hair or hair loss.

Prolonged rest causes inhibited qi and blood movement and hypofunction of the spleen and stomach, leading to poor appetite, mental fatigue, weak limbs, soft muscles, and obesity. Excessive mental rest causes a decline in thinking ability and lags in response.Lack of sexual activity restricts the free flow of qi and causes disharmony between the ren mai and chong mai, the reason for the occurrence of many diseases.

Traumatic injury leads to five sense organs or skin damage, stasis, swelling, pain,or broken bones and sinew injuries.

Elevated temperature or low temperature, such as scalding by water or fire, or burning or frosting by chemical substances, light, or electricity, may change the color of the skin to red, dark purple, or pale white. In serious cases, swelling and festering might occur.

Insect or animal bites may cause local damage to the skin, leading to dermatitis or allergic diseases.

Drug, light, or chemical toxins can cause eruptions. Ultraviolet light from sunshine may accelerate the degeneration of the skin and cause soot black macules, freckles,and sunburn. Stimulation by daily chemical products or poor quality cosmetics can lead to dermatitis and skin eruptions due to allergic reactions.

Blood stasis leads to many cosmetic conditions, such as a dim complexion, dark lips, dry itchy skin, dry hair, hair loss, soot black macules, dark circles under the eyes, spider angioma, and palmar erythema. Prolonged blood stasis may cause a blackish complexion and scaly skin.

Phlegm-fluid retention leads to acne nodosum, cystic acne, alopecia, deviated eyes and mouth, and obesity.

Congenital diseases include hereditary diseases and insufficient endowment, such as harelip, ichthyosis, the five kinds of flaccidity, and retardation.

Aging is a natural process. For women, aging begins with deficiency in the yangming channel, manifesting as aging on the face. For men, aging begins with deficiency of kidney qi, manifesting as aging of the teeth. Aging starts from the body, followed by dysfunction of the nine orifices, and then aging of the brain. Aging is a crucial factor in damaging the looks.