Summer heat, summer humidity and chronic disease management

This is the 3304th article of Da Yi Xiao Hu

It is the hottest time of the year, with continuous high temperatures, often accompanied by increased humidity, occasional short thunderstorms, long days and short nights, long hours of sunlight and strong radiation. These weather characteristics are the norm in the summer in the Jiangnan region. The two key words are "high temperature" and "high humidity", which cause a series of discomfort reactions in some people's bodies, and even more obvious symptoms. Chinese medicine calls them "summer heat (disease)" and "summer dampness (disease)".

1. Characteristics of Summer Heat and Summer Humidity

High temperature itself is a pathogenic factor, which Chinese medicine calls "summer evil", "summer heat evil" or figuratively called "fire heat evil". The effects of this pathogenic factor on the human body are mainly manifested in accelerated blood flow, dilation of skin capillaries, significantly increased sweating and decreased appetite. Therefore, people often feel thirsty, irritable, tired, and even panic, headache and other discomforts, and sometimes dry stools. This is what Chinese medicine calls "summer heat evil invading the human body can easily consume qi and damage body fluids."

In the eastern coastal, southern and southwestern regions of my country, high temperatures in summer are often accompanied by increased humidity (usually refers to humidity in the air > 60%), and this feature is particularly prominent in the southern region. Therefore, there is a discussion in traditional Chinese medicine that "heat is often accompanied by dampness", which is not only a description of the climate characteristics, but also emphasizes that the evil of heat (high temperature) and dampness (high humidity) often accompany and invade the human body "in harmony", which has a greater impact on the human body. This complex pathogenic factor is of course called "heat and dampness evil". The increase in humidity causes the air pressure to drop relatively, which is particularly prone to respiratory and circulatory system dysfunction, and also hinders the evaporation of sweat. Therefore, the main symptoms of heat and dampness are chest tightness and irritability, poor sweating, a sense of heat in the body that cannot be relieved, bitter and greasy mouth, loss of appetite, not only feeling easy to fatigue, but also feeling heavy and sleepy, even dizzy, unformed stool but poor excretion, and even sticky and burning sensation.

Generally, healthy people may experience some discomfort in the short term due to the invasion of summer heat and humidity, but they can usually tolerate it to a certain extent. As long as timely measures are taken to reduce the temperature, humidity, fluids and rest, the discomfort can be effectively alleviated. However, if effective measures are not taken in time to avoid the influence of summer heat and humidity, heat stroke may occur, and those who already suffer from chronic diseases and the elderly and young children with weak body regulation ability will be more affected, including sudden aggravation of the originally stable chronic diseases or the emergence of more serious complications. Especially for people with chronic cardiovascular and cerebrovascular diseases, the continued influence of summer heat and humidity may induce sudden fluctuations in blood pressure, aggravation of heart failure, acute cerebrovascular disease, etc.

2. How can patients with chronic diseases avoid the effects of summer heat and humidity?

Traditional Chinese medicine has the disease prevention principle of "nourishing the heart in summer". From the above explanation, we can find that the most prominent impact of summer heat and humidity on the human body is on the circulatory system, and various complications are caused by circulatory dysfunction; people with chronic diseases have a weaker ability to tolerate summer heat and humidity, so the key to preventing and treating diseases caused by summer heat and humidity is to stabilize the function of the circulatory system, which is what traditional Chinese medicine calls "nourishing the heart and calming the mind". Specifically, patients with chronic diseases, especially chronic cardiovascular and cerebrovascular diseases, should avoid emotional excitement and anxiety in summer, and develop the habit of regularly measuring heart rate, blood pressure, and blood sugar at home; patients with hypertension cannot reduce or stop medication on their own, and the adjustment of medication dosage must be based on regular monitoring and recording of blood pressure data. Consult a doctor; family oxygen therapy can be used to maintain a suitable blood oxygen level to avoid or reduce the increased burden on the heart and lungs caused by seasonal environmental factors; sudden severe or repeated unrelieved dizziness, headache, chest tightness, chest pain, palpitations, dyspnea, fever, vomiting, diarrhea, or even impaired consciousness, convulsions, etc., should go to the hospital in time.

In addition, we can also adjust our daily life, diet, activities/exercise, etc. to avoid or reduce the adverse effects of summer heat and humidity on the human body:

01

Live a regular life, keep calm and regulate your mood

The daytime hours in summer increase significantly. For the elderly or patients with chronic diseases who originally have reduced sleep time, the sleep quality may be more affected; even for generally healthy people, they often wake up early in the morning and go to bed late at night in summer. Insufficient sleep and decreased physical strength will significantly reduce the body's ability to tolerate summer heat and humidity. Therefore, it is very important for patients with chronic diseases to maintain a regular rest and daily routine and sleep quality in summer. Good sleep quality can also help stabilize emotions and maintain a stable psychological state. If the sleep time at night cannot be guaranteed, you can take a nap in the afternoon; avoid watching mobile phones and TV for a long time before going to bed, and avoid being in a more excited state of mind. High temperature and high humidity can make people irritable, anxious, and even irritable and emotionally volatile, and this state is more unfavorable for people with existing chronic diseases. In addition to maintaining a regular daily routine, when negative emotions occur, you can also soothe your emotions and adjust your mentality by communicating with family and friends, and diverting attention with some hobbies.

02

A healthy diet is important

The summer diet advocates "keeping warm, not overeating, eating regularly, and avoiding fatty and greasy foods."

① Don’t eat cold food just for the sake of coolness. A lot of cold food can easily damage the digestive function of the spleen and stomach. The human body’s digestive enzymes can function most efficiently within the normal body temperature range. If the food temperature is too low, the activity of the digestive enzymes will be reduced. Therefore, in summer, food should be fresh and kept slightly warm, which is conducive to digestion and absorption, and can also maintain the taste of food and improve appetite.

② Avoid being too hungry or too full when eating in summer. Eating too much at one time will not only increase the gastrointestinal burden, but also cause redistribution of circulating blood flow, which will have an adverse effect on the heart, lung, and brain circulation of patients with chronic diseases. Similarly, drinking water in summer should be "drinking in small amounts and multiple times at all times". Do not wait until you are thirsty to drink a large amount of water at one time. Such "binge drinking" will suddenly increase the circulatory capacity, increase the circulatory burden, and induce circulatory dysfunction in patients with chronic diseases.

③ The principle of a light diet in summer does not mean that everyone should only "eat vegetarian food". Maintaining rich nutrition, especially ensuring a certain amount of high-quality protein intake, will help improve the body's disease resistance. In the case of reduced appetite and weakened gastrointestinal function in summer, on the one hand, the proportion of high-energy food should be reduced to reduce the burden on the digestive system. On the other hand, in terms of food processing methods, less oil should be used, heavy flavors should be avoided, and frying and grilling should be avoided. Boiling and steaming should be used more often, which is conducive to digestion and absorption and reduces the destruction of nutrients. Patients with chronic diseases should not arbitrarily increase their sodium salt intake to avoid increasing the burden on circulation.

03

Cooling and dehumidification, safe entry and exit

There are many means and methods to maintain a suitable temperature for living, working and learning environments in summer. When lowering the ambient temperature, it is important to avoid too low a temperature, and the temperature difference between indoor and outdoor should not be too large. Especially for patients with chronic diseases such as arteriosclerosis, due to the weakened vasodilation and contraction regulation functions, if the ambient temperature changes drastically in a short period of time, it is easy to cause acute symptoms caused by circulatory dysfunction, such as drastic changes in blood pressure, acute cerebrovascular disease, aggravated myocardial ischemia and even acute myocardial infarction. When engaging in outdoor activities in summer, you must be prepared to prevent high temperatures and radiation, and the clothes you wear should be breathable; the elderly and patients with chronic diseases should try to avoid or reduce the frequency and time of outdoor activities during periods of high temperature and humidity. In addition to cooling the environment to prevent heatstroke, it is also important to reduce humidity to prevent heatstroke and humidity. In indoor environments, general air-conditioning equipment currently has a dehumidification function; in addition, it is also necessary to pay attention to the cleanliness of the indoor environment, reduce the random stacking of items, and the design and material selection of interior decoration, the placement of furniture and items, etc. should be conducive to air circulation and moisture-proof.

4. Scientific exercise to maintain health For most healthy people and some patients with mild chronic diseases whose conditions are under control, swimming is the most ideal exercise in summer. Exercising in a qualified and well-managed indoor swimming pool can not only avoid the harm of high temperature, but also improve cardiopulmonary function, reduce fat and increase muscle, and reduce the impact and load on the lower limb joints during exercise. What you need to pay attention to when swimming is: choose the frequency and amount of exercise according to your physical ability; warm up on the shore before entering the water; do not swim when you are hungry or after a full meal; do not force yourself to swim when you are unwell, tired, injured or have an acute illness. For more elderly people and people with chronic diseases, moderate and scientific exercise is very necessary, but outdoor exercise in summer must avoid high temperature periods, and outdoor activities should not be too long; it is recommended to exercise in the form of simplified Tai Chi, Eighteen Exercises, Eight-Section Brocade or radio gymnastics, and the amount of exercise is generally enough to cause slight sweating, slightly increased breathing rate and heart rate; after sweating during exercise, do not turn on the air conditioner, take a shower, or lie down or sit immediately, but wipe off the sweat in time, change wet clothes, and gradually stop activities.

3. Dietary prescription for preventing heatstroke and removing dampness

Barley and red bean soup has now become a household name for invigorating the spleen and removing dampness. In addition, there are many ingredients and recipes that have the effects of preventing heatstroke and removing dampness, as well as calming the mind and soothing the nerves. Winter melon is a good product for preventing heatstroke and removing dampness in summer. In addition to using the flesh for cooking, wash the winter melon peel and boil it with winter melon seeds as a substitute for tea. It has the effect of removing dampness and diuresis. If you add some lotus leaves, it has the effect of clearing heat and relieving summer heat, and also has the auxiliary function of regulating blood lipids. 3-6 grams of honeysuckle, 15-30 grams of Huai wheat, and 6-9 grams of black plums are boiled in 500-800 ml of water and drunk as a substitute for tea. It has the effect of clearing heat and astringing sweat, and calming the mind and soothing the nerves. Boil 3-6 grams of rose flowers and 15 grams of buckwheat (fried) with 500-800 ml of water and drink it as tea. It has the effects of strengthening the spleen and eliminating dampness, calming the liver and tranquilizing the mind. If you add 3-6 grams of chrysanthemum, it can enhance the effects of clearing heat, calming the liver and improving eyesight, and it also has the effect of assisting in regulating blood lipids and blood pressure.

Sanlin Kant Community Health Service Center, Pudong New Area, Shanghai

Written by Zhang Yanting, attending physician

Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine

Reviewed by He Miao, deputy chief physician