The separation of mind and body has a long history. Old philosophers like Descartes, who is one of the most famous proponents of the separation of mind and body, proposed that the mind has a supernatural origin while the body belongs to the material world. Descartes believed that the mind connects to the brain via the pineal gland. However, he could not explain how an immaterial entity can interact with a material thing. Modern science has shown that the mind originates from brain activity.

Positive emotions are associated with physical health

In all cultures and ancient civilizations, there are historical beliefs about the association between mood and diseases including Chinese traditional medicine and traditional Indian medicine, Ayurveda, and Egyptian ancestral medicine. Human beings in ancient times believed that their mental states were influenced by supernatural forces. Some old beliefs suggested that mental and physical health were influenced by sins committed in current or past lives. They believed that avoiding sin leads to relaxation, a positive mental state, and ultimately, physical health. These beliefs participated in the shaping and development of modern psychiatry.

There is an Iranian proverb that states: Laughter is the cure for all types of incurable illnesses. According to the search results, there is a correlation between humor and chronic physical illnesses. Humor therapy has been shown to alleviate chronic pain and promote happiness among older adults. Humor has also been shown to increase lung capacity, strengthen abdominal muscles, and boost the production of immunoglobulin A, which is one of the primary antibodies produced by the immune system. Humor causes reductions in cortisol, growth hormones, and epinephrine. Following laughter or other humorous encounters, natural killer cell activity, immunoglobulin G, and immunoglobulin M levels increase for as long as 12 hours.

Laughter improves glucose control in diabetic patients

Diabetes mellitus is a significant global health issue. It has been estimated that its prevalence will increase to over 7,000 per 100,000 by 2030. It is a risk factor for other deadly diseases, such as cardiovascular disorders and cancer. Hence, some researchers and physicians know it as the mother of all diseases. Type 2 diabetes mellitus, in contrast to type 1 diabetes, which is caused by a lack of insulin release, results from the dysfunction of the insulin hormone in target tissues such as muscle, fat, and liver. Insulin dysfunction is known as insulin resistance, and obesity and aging are the main risk factors for the onset of insulin resistance. Type 2 diabetes typically develops in adults who are over 40 years old. Despite new hope for a cure for diabetes in light of recent research, the prevalence and mortality rates of diabetes have increased.

Despite the need for additional research, studies suggest that there is a relationship between diabetes and positive emotions. Laughter has been shown to lower blood glucose levels, reduce the risk of microvascular complications such as kidney, retina, and nerve damage, and modulate immune function. Laughter has been reported to modify the levels of neuroendocrine factors involved in negative emotions and to accelerate glucose utilization by the muscles during a comedy show. Humor can modify the expression of genes involved in insulin dysfunction and the elevation of blood glucose. However, the underlying mechanisms for modifying insulin action and glycemic control through positive emotions are not yet fully understood.

On the other hand, negative emotions such as stress, anxiety, and depression can have a negative impact on diabetes management and increase the risk of developing type 2 diabetes. Psychological stress leads to the release of catecholamines and an increase in serum glucocorticoid concentrations, which can increase insulin requirements and insulin resistance. A study found that anxiety and depression scores were significantly higher in elderly people living independently with prediabetes and hypertension compared to participants with normal blood glucose levels. The study suggests that more attention should be paid to negative emotions in individuals with prediabetes and hypertension, as these findings could help inform health providers in developing interventions for this population.

Conclusion

With the integration of the brain and the mind, we expect to gain a deeper understanding of the interplay between the body, physical diseases, and mental states. However, despite the belief in the integrity between the body and mind, the shadow of old views still persists in the medical treatment of physical diseases. As Edward Bullmore explained in The Guardian in 2022, mental and physical diseases are currently being treated as separate entities. Physicians are responsible for the treatment of physical disorders, while psychiatrists or psychologists focus on mental illnesses. The role of mental states in the initiation and cure of physical diseases is often ignored, despite an abundance of evidence.

Several factors, including genetics, diet, a sedentary lifestyle, and the microbiome, contribute to the occurrence of type 2 diabetes. There is evidence to suggest that positive emotions and laughter can affect diabetes and blood sugar control. On the other hand, psychological stress promotes the onset of elevated blood sugar levels in individuals who are predisposed to diabetes. However, further research needs to uncover the role of humor in metabolic diseases. Laughter, which has no known side effects and is inexpensive, can be used for every patient with diabetes mellitus.