Can jokes cure dry eyes? This is no joke!

There are some lines in the classic crosstalk "Miraculous Hands Cause Diseases" by crosstalk masters Hou Baolin and Guo Qiru, "The advantage of crosstalk is here! It makes our audience laugh" and "The laughter of people can make the clear air rise, the turbid air fall, the food go to the large intestine, the water go to the bladder, the food and water are digested, and disasters and diseases are avoided. It is so wonderful that it is hard to describe it in detail. It can be used to communicate with gods. Please try it and you will know that what I said is not wrong!"

Crosstalk is about telling jokes and making people laugh. "When you laugh, you become younger; when you worry, your hair turns gray." If you laugh, you become younger; when you worry, your hair turns gray!

Laughter can make people feel refreshed, full of energy, prevent and cure diseases, and keep them healthy.

Recent scientific research shows that jokes can cure dry eyes, and this is no laughing matter!

1. Introduction to dry eye syndrome

Dry eye syndrome, also known as keratoconjunctivitis sicca, is a common and complex ophthalmic disease caused by insufficient tear secretion, excessive evaporation or abnormal tear composition, which can cause eye discomfort and visual dysfunction.

Symptoms of dry eye include eye fatigue, foreign body sensation, dryness, and in severe cases, burning sensation, soreness, redness, eye pain, photophobia, etc. Your eyes are like a dry desert, without the feeling of moisture. If dry eye is not treated in time, it may develop into corneal ulcer, perforation or secondary infection, which seriously threatens vision.

Staring at the computer or mobile phone screen for a long time, staying up late for a long time, and being in an air-conditioned environment for a long time are all common causes of dry eye. People with different ages, genders, medication history, and chronic diseases such as diabetes and rheumatoid arthritis are all high-risk groups. The incidence of dry eye in China is 21%-30%, and the probability of women and the elderly is higher.

In this digital age, we can hardly live without electronic screens, whether for work, study or entertainment. Staring at the screen for a long time may cause dry eyes, itching and foreign body sensation. These symptoms may be reminding you that dry eye syndrome has come to you.

However, do you know that there is a simple and fun way to effectively relieve your dry eyes? That is - laugh! You heard it right, the dry eyes that make your eyes dry and uncomfortable can actually be defeated by laughing.

2. Can jokes cure diseases? This is definitely not a joke!

You might be thinking, how can jokes cure dry eyes? It sounds like a joke. But wait, let's take a look at what the scientific research says.

On September 12, 2024, the Zhongshan Eye Center of Sun Yat-sen University released a latest research result, confirming that the therapeutic effect of "laughter training" on dry eyes is comparable to that of artificial tears 0.1% sodium hyaluronate, and even better than the latter in some aspects. This study was published in the British Medical Journal and has attracted widespread attention. The research team selected nearly 300 patients with mild to moderate dry eyes and randomly divided them into two groups, receiving 8 weeks of artificial tear treatment and "laughter training" respectively. The results showed that after 8 weeks of intervention, the symptoms and signs of patients in the "laughter training" group improved, and the effect was no less than that of the artificial tears group, and even better than the latter in stabilizing some indicators of the tear film and improving the secretion function of the meibomian glands.

So how does laughter relieve dry eyes? The biomechanical mechanism behind this is actually quite interesting.

3. The biomechanical mechanism behind how laughter relieves dry eyes

Tears are a transparent liquid secreted by the lacrimal glands, accessory lacrimal glands, meibomian glands and conjunctival goblet cells. Tear secretion includes two types: basal secretion and reflex secretion. Basal secretion is continuous and small in quantity, not controlled by nerves, and is mainly used to moisten the eyeball; reflex secretion is mainly controlled by the sympathetic and parasympathetic nerves. When the eyes are stimulated or the body is mentally stimulated, a large amount of tear secretion will be produced.

Tears are the key to keeping the eyes moist and comfortable. They not only lubricate the surface of the eyeball, but also remove foreign matter and harmful substances from the surface of the eyeball. However, patients with dry eyes often have insufficient tear secretion or abnormal tear composition, which leads to dryness and discomfort on the surface of the eyeball. Shedding tears is such a simple thing, but it has become a difficult luxury for patients with dry eyes!

If you want to shed tears to relieve the discomfort of dry eyes, then cry! Why laugh?

Laughter may seem like a facial expression, but it is actually a whole-body activity. When we laugh, our facial muscles will unconsciously contract and relax, which helps promote blood circulation and improve eye microcirculation. At the same time, laughter also activates the autonomic nervous system and stimulates the secretion of tears.

There is a saying that goes, "I laughed so hard that I cried" (Figure 1). Why is it so?

Figure 1 I laughed until tears came out

From a physiological point of view, when we laugh, our facial muscles will contract and relax violently. This process may indeed stimulate the tear glands around the eyes, leading to the production of tears. First, we need to understand the tear system in the eyes. The tear system includes the tear glands and tear ducts, and its main function is to produce and discharge tears (Figure 2 left). The tear glands are innervated by the tear gland nerves and are reflex secretory glands. When emotions are excited (such as laughing, crying, etc.), the tear glands will secrete more tears.

Figure 2 When we laugh, the contraction of our facial muscles causes the tear glands to secrete more tears, which also increases the pressure in the area around the tear ducts.

Laughing and crying can both produce more tears. From a biomechanical point of view, the contraction of facial muscles promotes tear production in the same way. In addition, the biomechanical principle of tears when yawning is roughly the same. Just open your mouth wide, close your eyes, take a deep breath, and imitate the movements and expressions of yawning to produce tears - it works.

Secondly, when laughing, the facial muscles will contract and relax violently, and the eyes will squint unconsciously. This process involves multiple muscle groups, including the orbicularis oculi and zygomaticus major muscles (Figure 2 right). The contraction of the orbicularis oculi squeezes the meibomian glands in the eyelids, prompting the secretion and discharge of oil (Figure 3). The oil secreted by the meibomian glands is an important component of the tear film, which can prevent tears from evaporating too quickly, thereby keeping the eyes moist and comfortable.

Figure 3 Meibomian glands secrete oil

This tear film is only 1/10 as thick as an A4 paper, but it can be divided into 3 layers, from the outside to the inside, namely the lipid layer, the aqueous layer and the mucin layer. The lipid layer mainly plays a protective role. On the one hand, a healthy lipid layer can buffer and reduce the mechanical stimulation during blinking. On the other hand, it is like a layer of oil, covering the aqueous layer to prevent rapid evaporation of water. If the lipid layer is normal, the tear film can reflect brilliant colors, and the eyes are moist and comfortable. But if the lipid layer is reduced, it will appear grayish white, which may lead to abnormal tear film function and induce dry eye syndrome. Patients with dry eye syndrome often have abnormal meibomian gland function, resulting in insufficient or poor oil secretion, which further aggravates the dryness and discomfort on the surface of the eyeball.

In addition, when we laugh, we are in a state of abdominal breathing, which can activate the parasympathetic nerves and stimulate the tear glands to secrete tears. Specifically, laughter can promote the body to release endorphins. Endorphins are a natural "happy hormone" that can reduce stress, relieve pain, and enhance immunity. When we laugh, the body releases a large amount of endorphins, which can reach the eyes through the blood circulation and stimulate blood circulation in the eyes. Good blood circulation is very important for the health of the eyes. It can provide sufficient oxygen and nutrients to the eyes, while taking away metabolic waste. When the blood circulation in the eyes is accelerated, the secretion function of the tear glands will also be enhanced, thereby increasing the secretion of tears. Moreover, laughter can stimulate the nervous system to release neurotransmitters such as dopamine, which can improve mood and reduce anxiety and depression. When our mood becomes better, the body's stress response will also be reduced, which helps to relieve the symptoms of dry eyes.

4. Specific methods of laughter training

Having said so much, you may be eager to try "laughter training". So, how to do it specifically?

Don't worry, the research team has designed a set of simple and interesting "laughter training" commands for us: "Hahaha, hahaha, eggplant, eggplant, 7-Up, 7-Up, 7-Up, money, money, hahahahahaha..." You just need to follow the commands, make expressions and sounds as exaggerated as possible, and you can start training.

The specific steps are as follows: Find a quiet and comfortable place, sit or stand up straight, and relax your facial muscles. Follow the command "Haha, Haha, Eggplant, Eggplant, 7-up, 7-up, Money, Money, Money, Hahahahaha..." to start training. Repeat the command 30 times each time as one training session, and train 4 times a day. During training, make exaggerated expressions and sounds as much as possible to fully exercise your facial muscles. At the same time, keep your breathing smooth and don't hold your breath.

The research team also developed a small program to assist in the training. This small program has multiple functions, including reminding everyone to "check in at a certain time" to complete the training, and built-in facial recognition function to judge whether the subject's smile is big enough. In this way, you can train anytime and anywhere.

If you feel embarrassed to laugh in front of others, you can also find a quiet place by yourself - just laugh in private!

5. The magical effect of laughter training

So, how magical is "laughter training"? Let's take a look at the data from scientific research!

The research team conducted an 8-week intervention study on patients with mild to moderate dry eye. The results showed that the ocular surface disease index score (a measure of the subjective severity of dry eye) of the patients in the "laughter training" group decreased by an average of 10.5 points, while the artificial tears group decreased by an average of 8.83 points. This shows that "laughter training" is no less effective than artificial tears in reducing dry eye symptoms.

In addition, the research team also found that "laughing training" is even better than artificial tears in stabilizing some indicators of the tear film and improving the secretion function of the meibomian glands. Specifically, the non-invasive tear breakup time (an indicator of tear film stability) of patients in the "laughing training" group was extended by an average of 2.30 seconds, while there was no significant change in the artificial tear group. At the same time, the meibomian gland function of patients in the "laughing training" group was also significantly improved.

What is even more surprising is that the improvement effect of "laughter training" still persisted 12 weeks after the intervention was stopped. This shows that "laughter training" not only has short-term effects, but also long-term effects.

6. The potential for widespread application of laughter training

"Laughter training" not only provides a new treatment method for patients with dry eyes, but also has wide application potential.

First of all, "laughter training" is a non-drug treatment method with low price. Compared with artificial tears, "laughter training" has the advantages of safety, low cost and environmental friendliness. It does not require any drug or equipment assistance, and only requires the patient to train himself. In this way, the economic burden on patients and the environment can be greatly reduced.

Secondly, "laughter training" is suitable for all kinds of people, young and old. Young people and old people, men and women, dry eye patients and healthy people can all do the training. Moreover, "laughter training" can also be used as a daily health care method. Regular training can keep the eyes moist and comfortable and prevent the occurrence of dry eyes.

Finally, "laughter training" can also be used in combination with other treatments. For patients with severe dry eye, "laughter training" may not be able to completely replace drug therapy or surgical treatment. But it can be used as an auxiliary treatment method and combined with drug therapy or surgical treatment to improve the treatment effect and the patient's quality of life.

In addition to relieving and treating dry eyes, laughter can bring many benefits. It can stimulate the brain to release dopamine and other neurotransmitters. These neurotransmitters can improve mood and relieve negative emotions such as stress and anxiety. Laughter can enhance immune function and stimulate the immune system to produce more antibodies and white blood cells, thereby enhancing the body's immunity. Laughter can also exercise facial muscles, enhance the strength and elasticity of facial muscles, and prevent facial sagging and wrinkles. Laughter can also promote breathing and increase lung capacity. Laughter can also improve cardiovascular health, relieve pain, enhance memory, and increase affinity between people. Laughter is simply a magical power!

Laughing is good, but don't be too greedy. Laughing too much may cause stomachache, breathing difficulties, or even inability to laugh. If you are interested, please follow my personal WeChat public account "Medical Biomechanics" and read the article: It's so funny!

VII. Conclusion

In this fast-paced era, we are often busy with work, study and life, and neglect our mood and health. Dry eyes are like the Sahara Desert running into the eyes! It is painful. Fortunately, laughter can make us happy and healthy. In daily life, often telling jokes and laughing heartily can have a miraculous effect on preventing and treating dry eyes. Jokes can cure dry eyes, this is by no means a joke.

If you really feel dry, itchy or have a foreign body sensation in your eyes, why not try "laughter training"! Maybe it will become your "secret weapon" to relieve and treat dry eyes! By regularly practicing "laughter training", we can not only relieve and treat eye diseases such as dry eyes, but also improve mood, relieve stress, and enhance immunity.

Although crying can produce more tears, it is better to laugh than cry in life! I would like to share with you a classic song. Lyrics by Kai Chuan, music by Martin, sung by Wang Jieshi and Xie Lisi:

Although sadness and distress are inevitable in life,

You will always find happiness and joy on the road of life.

My friend, do you like to cry or laugh?

Look at the spring coming back to earth, the sun is shining, youth is so beautiful,

Don't let your tears immerse you in trouble.

Laughing is better than crying, laughing is better than crying, laughing is better than crying...