Wear a smile and have friends; wear a scowl and have wrinkles — George Eliot

A smile that is suppressed is an opportunity for joy that is missed. Little thought is given to smiling by most of us, especially now that we wear masks that hide our smiles. But smiles are not unnatural. In fact, smiles are innate, and our body wishes us to smile as much as possible because it’s a form of social bonding, something that protects and preserves that which is human in us.

Even our animals, especially dogs, respond to a smile. Try it the next time you’re around your dog or a friend’s dog. Smile and watch what happens.

Enter the Field of PNI

Copious research has indicated over the decades that mood is moderated by the immune system and maybe a protective means of allowing our body to repair. In other words, if we have an illness, the immune system tamps down our mood so that we are less likely to move about and engage in regular activities.

The lack of engagement then allows our bodies to repair. Therefore, the immune system does moderate mood, and, conversely, mood can affect the immune system.

Studies have shown both of these effects, and one study specifically looked at what was known as “the pursuit of happiness.” Interestingly, while a doctoral student, who is now a psychoimmunology professor, Steve Cole noted that his hobby of matching art buyers with artists gave him a great degree of pleasure. As he noted, “…there was an extra layer of purpose. I love the ability to help artists I thought were great to find an appreciative audience.”

As a result of his activities, he began to question how this might have affected him on a biological level. Of course, today the field of psychoneuroimmunology (PNI) is one that strongly supports the idea that we can manage our nervous and immune system by our emotions. But not at that time, and it was highly speculative.

The question is still being asked if we can do this actively when we are not feeling particularly upbeat. Testing the idea of mind-body interaction, Dr. Steve Cole and his colleagues began studying lonely people to see how they might be affected physically by the idea of a lack of socializing with others.

With his colleagues, Cole has published a string of studies suggesting that negative mental states such as stress and loneliness guide immune responses by driving broad programs of gene expression, shaping our ability to fight disease. If he is right, the way people see the world could affect everything from their risk of chronic illnesses such as diabetes and heart disease to the progression of conditions such as HIV and cancer.

Two Kinds of Smiles

The ability to give facial expression to our emotions appears at an early stage of infancy. Thus, the face is a fulcral element in human interaction from a very tender age — and indeed is the first means of communication from which we can draw.

…happiness is not always signaled by a smile. For example, the smile of a child is more evident in the context of social interaction than in situations of happiness and can also be observed more in situations of discomfort. This type of smile may, in fact, be more indicative of a negative state.

Two types of smiles, therefore, have been characterized by researchers; the forced smile and the Duchenne smile. In the latter, the lower eyelids dilate and the corners of the eye wrinkle. It is an indication of genuine positive emotion while the former complies with a situation or a person. The person or a child is doing what is expected, not expressing genuine positive emotion.

The “true smile” is named for Duchenne de Boulogne who was a neurologist who used electrical stimulation on patients for his facial expression experiments — not always resulting in smiles, but grimaces that appear tortuous. “This is best exemplified by his investigation of the mechanisms of human physiognomy in which he used localized faradic stimulation to reproduce various forms of human facial expression.” We have to wonder what his hypothesis was for these experiments.

Manipulation of Laughing/Smiling

Does smiling or laughing directly affect our body’s “feel good” hormones and thereby affect our mood? One small research study seemed to point in that direction.

Dr. Michael Lewis injected Botox into crow’s feet laugh lines of his subjects (crow’s feet are associated with Duchenne smiles) and found they reported feeling more depressed.

On the contrary, when this same procedure was used on frown lines, subjects reported feeling less depressed. The facial feedback loop to the brain’s dopamine and serotonin would seem to have been affected, but no tests were performed to verify this change.

But the very act of smiling can help in reducing the heart rate. Further studies have shown that “…smiling may actually influence our physical state: compared to participants who held neutral facial expressions, participants who were instructed to smile, and in particular those with Duchenne smiles, had lower heart rate levels after recovery from the stressful activities.”

Our Immune System

A delicate interplay of systems can best be seen by the illustration here. As you can see, there is a constant back-and-forth relationship where the environment, the brain, and the body all work together. The ultimate goal is homeostasis, with all systems working in harmony and keeping us healthy in the process.

If laughing and smiling are good influences on this important health-maintaining body system, it would seem therapeutic. In fact, Norman Cousins, a well-known journalist/writer who had developed ankylosing spondylitis and a cardiac condition, was a proponent of laughter in the cause of health.

Cousins’ crusade for laughter attracted medical experts’ attention, who indicated a degree of surprise that he, seemingly, had lengthened his life through laughter. His favorite activity was watching Groucho Marx videos.

An institute of PNI was established at UCLA’s school of medicine due to Cousins’ encouraging work in this area, and he became a professor at the school. The case appeared to have been made that laughter was a good addition to medical therapeutics.

After this pioneering step, laughter and smiling were included in many medical curricular around the country. In fact, laughter in a medical setting was a technique utilized by the famous Patch Adams (Dr. Hunter Doherty “Patch” Adams).

DNA and Laughing

Are we born to laugh or not? It would seem that our DNA does influence how readily we laugh or not.

In a new study linking a gene to positive emotional expressions such as smiling and laughing, researchers demonstrated that people with a certain genetic variant — those with short alleles of the gene 5-HTTLPR — smiled or laughed more while watching cartoons or subtly amusing film clips than people with long alleles.

But are we servants of our DNA and those few alleles that may push for or against laughing? The mystery remains unsolved at this time. However, the human body still hasn’t given up all its mysteries, and this may be one of them.

Are we still evolving and making discoveries, or has evolution stopped? We only recently uncovered one of the body’s mysteries, the glymphatic system.

I suggest we are evolving and, perhaps, we may tip the scales a bit in favor of laughter and smiling if we try hard enough. Who knows, Jean-Baptiste Lamarck might have been right all along, and all the credit for evolution should not have gone to Charles Darwin.