It is the first thing we do when we come out of our mother’s womb.

All of us do it at one point or another throughout our lives.

We cry.

It can be because of happiness or sadness. From pain or even relief. Experts say that there are three kinds of tears: basal tears that line our eyes and keep them wet and healthy, emotional tears that are triggered by strong feelings, and reflex tears that are shed because of irritants including chemicals.

Dr. Claudia Arroyave, an ophthalmologist at the University of Miami Miller School of Medicine’s Bascom Palmer Eye Institute—which has been ranked the No. 1 eye hospital in the country 22 times by U.S. News & World Report—discusses the intricacies of crying. 

“Crying is primarily a physiological response triggered by various emotional, physical, and environmental stimuli,” she said.

What are the physical reasons we cry?

Emotional response: sadness, grief, happiness, frustration, or even relief. Tears are produced in response to heightened feelings, and the act of crying can serve as a cathartic release, helping to alleviate tension.

Biological response: Tears are produced by the lacrimal glands located above each eye. These glands continuously produce basal tears to keep the eyes lubricated and protect them from dust, debris, and bacteria. However, during times of strong emotion or stress, the nervous system can stimulate the production of additional tears, leading to crying.

Stress relief: Crying has been shown to activate the parasympathetic nervous system, which helps to counteract the effects of the sympathetic nervous system, responsible for the body's “fight or flight” response. This can help to reduce feelings of stress and promote relaxation.

Social communication: Crying is also a form of nonverbal communication, signaling distress or vulnerability to others. It can elicit empathy and support from those around us.

Pain response: In some cases, crying can be a physiological response to physical pain or discomfort. Tears contain natural painkillers, such as endorphins, which can help to alleviate pain and promote healing.

Can a person cry and not produce tears?

Crying is a natural and complex physiological and emotional response that involves the shedding of tears, often accompanied by vocalizations and facial expressions. It is a fundamental aspect of human behavior and serves various purposes.

Physiologically, crying involves the secretion of tears from the lacrimal glands. Yes, it is possible for a person to cry without producing tears, although it's less common.

There are several reasons why someone might experience crying without tears. They are:

• Dry eye syndrome: The eyes do not produce enough tears, or the tears evaporate too quickly. This can lead to symptoms such as eye irritation, redness, and a sensation of dryness, even when crying.

• Emotional response without tears: Sometimes, strong emotions can trigger the physiological response associated with crying, such as changes in heart rate, breathing, and facial expressions, without necessarily causing tears to be produced. This might occur in situations where the emotional response is intense but does not manifest in the same way as typical crying.

• Emotional numbness: In some cases, individuals may experience emotional numbness or suppression, where they are unable to express their emotions fully, including through crying.

Medication side effects can also trigger tearless crying.

Some individuals have conditioned themselves to suppress the physical expression of tears while still experiencing emotional distress.

Can it be a way for the eye to protect itself?

Crying can indeed serve as a way for the eye to protect itself. Tears play several essential roles in maintaining eye health and protecting the eye from various external threats. Here are some ways in which crying helps to safeguard the eyes:

• Lubrication: Tears provide lubrication to the surface of the eye, keeping it moist and preventing dryness, which is essential for maintaining clear vision and preventing discomfort or irritation caused by friction between the eyelid and the cornea.

• Clearing debris: Tears contain enzymes and antibodies that help to flush out debris, dust, and foreign particles that may come in contact with the eye.

• Preventing infection: Tears have antimicrobial properties that help to inhibit the growth of bacteria and other microorganisms on the surface of the eye.

• Healing: Tears contain growth factors and proteins that promote the healing of minor abrasions or injuries to the surface of the eye. By providing a nourishing environment for the eye's tissues, tears aid in the repair process and help to expedite healing.

• Emotional regulation: Crying in response to emotional stimuli can also indirectly benefit the eyes by stimulating tear production. Emotional tears contain higher levels of certain proteins and hormones that may have additional protective effects on the eyes, such as reducing inflammation or promoting tissue repair.

Overall, crying serves as a multifaceted mechanism for maintaining eye health and protecting the eyes from a range of potential threats. By promoting tear production, crying helps to ensure that the eyes remain well-lubricated, clean, and resilient in the face of environmental challenges.

Can we stop crying at will? Or is it a response, like vomiting, that cannot be stopped?

Crying involves autonomic nervous system activation, similar to involuntary responses like vomiting. While not as uncontrollable as vomiting, the physiological response can sometimes make it difficult to stop crying immediately.

Vomiting is an involuntary reflex triggered by the brain in response to specific stimuli, such as toxins, gastrointestinal distress, or intense motion. It is much more difficult to control voluntarily because it involves a series of coordinated muscular contractions and neural responses designed to expel harmful substances from the body.

Crying, while also having a strong physiological component, is more influenced by cognitive and emotional factors. People often have some degree of control over their tears, especially if they use deliberate strategies to manage their emotional state.

While crying can be controlled to a certain extent through various techniques, it is not as entirely involuntary as vomiting. The ability to stop crying at will varies from person to person.

Is it dangerous to not be able to produce tears?

Yes, it can be dangerous not be able to produce tears. Risks include:

• Corneal damage: Tears provide necessary lubrication to the cornea, the transparent front part of the eye. Lack of tears can lead to corneal dryness, abrasions, and in severe cases, corneal ulcers and perforation. These conditions can cause significant pain and potentially lead to vision loss if left untreated.

• Inflammation: Chronic dry eyes can cause inflammation of the ocular surface, leading to redness, swelling, and discomfort. This inflammation can exacerbate the symptoms and create a cycle of worsening dryness and irritation.

• Blurred vision: Tears form a smooth tear film over the cornea, which is essential for clear vision. Insufficient tear production can lead to an uneven tear film, causing intermittent blurred vision and difficulty focusing.

• Eye discomfort: Common symptoms of dry eyes include a gritty or sandy sensation, burning, redness. These symptoms can affect the quality of life, making it uncomfortable to read, use a computer, or perform other daily activities.