KORN KURATED RESEARCH

Circadian Rhythm Imbalance and Its Effects on Individuals and Community Health

The disruption of our circadian rhythm (CR) affects reproductive health and contributes to earlier menarche onset and hormonal imbalances. These disruptions also influence conditions such as substance use disorders, cancer progression, and metabolic diseases, emphasizing the need for further research and public health interventions.

Balancing the circadian rhythm (CR) is the quintessential health goal, ensuring good mental and physical health. CR underlies sleep, mood (including depression and PTSD), energy, and binge eating behaviors. Bipolar disorder is a CR disorder, and by balancing CR, we can make significant progress. Disrupted CR is a disease of modern life; our ancestors went to sleep in the dark (or had dimly lit fires, candles, or lanterns) and woke up with the light. They often awakened in the middle of the night around 3 a.m. and spent an hour in reverie, integrating visions and dreams into their lives before dozing back to sleep.

I am always eager to read new research on circadian rhythm. The first study examines the connection between glucose, diabetes, and disrupted circadian rhythm. Here, we have two modern diseases intersecting: Type 2 Diabetes, which rarely, if ever, occurred prior to the late 19th century, and circadian disruption due to artificial light. Ironically, the rise of access to refined sugar and increased cases of Type 2 Diabetes in the 1930s coincides with the electrification of the United States in rural areas.

The second research paper looks at the age of menarche onset, which occurs relatively earlier in urban females than in females raised in rural areas in Nigeria. This effect of earlier age of onset is also seen in the United States with exposure to pesticides and chemicals that act as endocrine disruptors.

My clients often ask how long I recommend they take nutrients or detoxify. I answer, "How long will you be exposed to multiple toxins and stressors?"

Article 3 leads us to the role of disrupted CR and cancer. It is well-established that people who work the night shift have a higher risk of cancer. CR imbalance contributes to tumor development.

The fourth research paper highlights how, in addition to the sleep-wake cycle and stress hormone rhythms, CR also contributes to the reward system—so it makes sense that disruption to sleep contributes to substance abuse. We know that PTSD and the strong association between PTSD and substance abuse also disrupts CR.

This review of circadian rhythm research suggests that a balanced rhythm governs all paths to mental and physical health. Stabilizing sleep is our first goal in treating mental distress. I trust you'll find these articles both accessible and valuable.

Tags: circadian rhythm, artificial light, cancer, diabetes type 2, substance use disorders

Interested in Learning More?

• Course(s): Mental Health Disorders
• Course(s): Diabetes Type 2, Cognitive Decline, and Alzheimer’s
• Course(s): Tapering Off Psychotropic Medications: Integrative and Naturopathic Strategies
• Book(s): Rhythms of Recovery
• Book(s): The Brainbow Blueprint
• Book(s): Natural Woman

Referenced Research Publications

Diabetes & metabolism journal
2024 Sep
DOI: 10.4093/dmj.2024.0237

Artificial Light at Night and Type 2 Diabetes Mellitus

Abstract

The widespread and pervasive use of artificial light at night (ALAN) in our modern 24-hour society has emerged as a substantial disruptor of natural circadian rhythms, potentially leading to a rise in unhealthy lifestyle-related behaviors (e.g., poor sleep; shift work). This phenomenon has been associated with an increased risk of type 2 diabetes mellitus (T2DM), which is a pressing global public health concern. However, to date, reviews summarizing associations between ALAN and T2DM have primarily focused on the limited characteristics of exposure (e.g., intensity) to ALAN. This literature review extends beyond prior reviews by consolidating recent studies from 2000 to 2024 regarding associations between both indoor and outdoor ALAN exposure and the incidence or prevalence of T2DM. We also described potential biological mechanisms through which ALAN modulates glucose metabolism. Furthermore, we outlined knowledge gaps and investigated how various ALAN characteristics beyond only light intensity (including light type, timing, duration, wavelength, and individual sensitivity) influence T2DM risk. Recognizing the detrimental impact of ALAN on sleep health and the behavioral correlates of physical activity and dietary patterns, we additionally summarized studies investigating the potential mediating role of each component in the relationship between ALAN and glucose metabolism. Lastly, we proposed implications of chronotherapies and chrononutrition for diabetes management in the context of ALAN exposure.

Keywords: Circadian rhythm; Diabetes mellitus, type 2; Dietary patterns; Exercise; Insulin resistance; Light pollution; Sleep.

Reference

Baek, J. H., Zhu, Y., Jackson, C. L., & Park, Y. M. (2024). Artificial Light at Night and Type 2 Diabetes Mellitus. Diabetes & metabolism journal, 48(5), 847–863. https://doi.org/10.4093/dmj.2024.0237

Journal of reproduction & infertility
2024 Jul-Sep
DOI: 10.18502/jri.v25i3.17011

The Influence of Artificial Light Exposure on Indigenous Populations: Exploring Its Impact on Menarcheal Age and Reproductive Function

Abstract

The impact of artificial light exposure on human health has garnered significant attention in recent years. In particular, its effects on reproductive health have raised concerns. Given that the onset of menarche serves as a crucial indicator of reproductive maturity, understanding the implications of artificial light exposure becomes paramount. Age of menarche onset occurs relatively earlier in urban females than females raised in rural areas. Besides the decline in age of menarche onset, exposure to artificial light may contribute to impairment in reproductive hormones, particularly gonadotropins, by disrupting rhythms of reproductive hormones, modulating stress hormones and kisspeptin productions, and causing body weight changes. This drastic environmentally induced change may increase the proportion of teenage pregnancies, unfulfilled childhood dreams, depression, and ill-prepared marriages, thus creating a potential need for public health intervention. Due to limited studies and often lack of longitudinal data, a significant knowledge gap exists in unraveling the potential mechanism involved in alteration of these physiologic processes. The purpose of the current review was to elucidate the intricate interplay between environmental factors, cultural practices, and biological processes within indigenous communities. By meticulously examining the multifaceted influences of artificial light, including its prevalence and varying intensity based on geographical locations and light pollution levels, this study aimed to provide scholarly insights in-to the pathophysiologic mechanisms underlying the observed changes. The findings of this inquiry will also inform evidence-based strategies and interventions aimed at safeguarding the reproductive well-being of indigenous populations amidst the escalating challenges posed by artificial light exposure.

Keywords: Artificial night lighting; Circadian rhythm; Community health; Hormones; Menarche; Reproductive health.

Copyright© 2024, Journal of Reproduction & Infertility.

Reference

Adeniyi, M. J., Awosika, A., Idaguko, C. A., & Ekhoye, E. (2024). The Influence of Artificial Light Exposure on Indigenous Populations: Exploring Its Impact on Menarcheal Age and Reproductive Function. Journal of reproduction & infertility, 25(3), 171–183. https://doi.org/10.18502/jri.v25i3.17011

International journal of molecular sciences
2024, May 28
DOI: 10.3390/ijms25115846

The Relationship Between Circadian Rhythm and Cancer Disease

Abstract

The circadian clock regulates biological cycles across species and is crucial for physiological activities and biochemical reactions, including cancer onset and development. The interplay between the circadian rhythm and cancer involves regulating cell division, DNA repair, immune function, hormonal balance, and the potential for chronotherapy. This highlights the importance of maintaining a healthy circadian rhythm for cancer prevention and treatment. This article investigates the complex relationship between the circadian rhythm and cancer, exploring how disruptions to the internal clock may contribute to tumorigenesis and influence cancer progression. Numerous databases are utilized to conduct searches for articles, such as NCBI, MEDLINE, and Scopus. The keywords used throughout the academic archives are "circadian rhythm", "cancer", and "circadian clock". Maintaining a healthy circadian cycle involves prioritizing healthy sleep habits and minimizing disruptions, such as consistent sleep schedules, reduced artificial light exposure, and meal timing adjustments. Dysregulation of the circadian clock gene and cell cycle can cause tumor growth, leading to the need to regulate the circadian cycle for better treatment outcomes. The circadian clock components significantly impact cellular responses to DNA damage, influencing cancer development. Understanding the circadian rhythm's role in tumor diseases and their therapeutic targets is essential for treating and preventing cancer. Disruptions to the circadian rhythm can promote abnormal cell development and tumor metastasis, potentially due to immune system imbalances and hormonal fluctuations.

Keywords: cancer; circadian rhythm; melatonin; suprachiasmatic nucleus.

Reference

Munteanu, C., Turti, S., Achim, L., Muresan, R., Souca, M., Prifti, E., Mârza, S. M., & Papuc, I. (2024). The Relationship between Circadian Rhythm and Cancer Disease. International journal of molecular sciences, 25(11), 5846. https://doi.org/10.3390/ijms25115846

Clocks & sleep
2024, August 19
DOI: 10.3390/clockssleep6030030

Disrupted Circadian Rhythms and Substance Use Disorders: A Narrative Review

Abstract

Substance use disorder is a major global health concern, with a high prevalence among adolescents and young adults. The most common substances of abuse include alcohol, marijuana, cocaine, nicotine, and opiates. Evidence suggests that a mismatch between contemporary lifestyle and environmental demands leads to disrupted circadian rhythms that impair optimal physiological and behavioral function, which can increase the vulnerability to develop substance use disorder and related problems. The circadian system plays an important role in regulating the sleep-wake cycle and reward processing, both of which directly affect substance abuse. Distorted substance use can have a reciprocal effect on the circadian system by influencing circadian clock gene expression. Considering the detrimental health consequences and profound societal impact of substance use disorder, it is crucial to comprehend its complex association with circadian rhythms, which can pave the way for the generation of novel chronotherapeutic treatment approaches. In this narrative review, we have explored the potential contributions of disrupted circadian rhythms and sleep on use and relapse of different substances of abuse. The involvement of circadian clock genes with drug reward pathways is discussed, along with the potential research areas that can be explored to minimize disordered substance use by improving circadian hygiene.

Keywords: artificial light at night; circadian rhythms; clock genes; sleep; substance use disorders.

Reference

Sharma, P., & Nelson, R. J. (2024). Disrupted Circadian Rhythms and Substance Use Disorders: A Narrative Review. Clocks & sleep, 6(3), 446–467. https://doi.org/10.3390/clockssleep6030030