The study synthesizes previous research to propose that contemplative practices like meditation and mindful breathing can help individuals spend more time in this deep rest state, optimizing the body's restorative capacities (Crosswell et al., 2024).

The researchers suggest that to achieve deep rest, three essential components must be present: physical safety, psychological safety, and parasympathetic nervous system (PNS) dominance. They emphasize the role of slow, rhythmic breathing as central to activating the PNS, which sends safety signals to the brain and decreases threat arousal. This physiological response fosters inner peace and tranquility, allowing both the mind and body to enter a state of restoration and healing.

A key outcome of this hypothesis is that the state of deep rest may enhance cellular restoration. When the body is not in a state of stress, more energy can be directed toward healing processes, improving mitochondrial function and overall cellular health. This model provides a holistic understanding of how mind-body practices, through deep rest, can support long-term wellness and stress reduction.

In summary, the findings suggest that contemplative practices that cultivate deep rest could be an effective strategy for reducing stress and promoting better overall health. By prioritizing safe environments and engaging in slow rhythmic breathing, individuals can enhance their mental and physical well-being (Crosswell et al., 2024).

Citation: Crosswell, A. D., Mayer, S. E., Whitehurst, L. N., Picard, M., Zebarjadian, S., & Epel, E. S. (2024). Deep rest: An integrative model of how contemplative practices combat stress and enhance the body’s restorative capacity. Psychological Review, 131(1), 247–270. https://doi.org/10.1037/rev0000453

These factors increase the risk of heart disease and type-2 diabetes. Researchers have long speculated that chronic inflammation may be the pathway linking perceived stress to metabolic dysfunction, as the body’s sympathetic nervous system is overactivated under stress. This study, Inflammatory biomarkers link perceived stress with metabolic dysregulation (Jurgens et al., 2023), aimed to analyze if inflammation is the dominant pathway for this relationship, providing a basis for stress-reduction interventions to target metabolic syndrome.

The study used data from the MIDUS project, focusing on participants who completed the Perceived Stress Scale (PSS) questionnaire alongside blood draws and physical exams. The final analysis included 648 individuals, excluding those with diabetes or cardiovascular disease. Inflammation was measured using five biomarkers—C-reactive protein, IL-6, E-selectin, fibrinogen, and ICAM-1—and metabolic function was assessed through blood pressure, BMI, lipids, blood sugar, and insulin levels. Researchers employed structural equation modeling to explore how inflammation mediates the relationship between stress and metabolic dysfunction.

The key findings of the study indicated a significant link between perceived stress and metabolic dysfunction, with inflammation acting as a primary pathway. Specifically, higher stress levels were associated with greater inflammation, which was then connected to worse metabolic measures. Inflammation accounted for 61.5% of the association between stress and metabolic dysfunction, suggesting it plays a dominant role in this process. However, other factors, such as poor lifestyle choices, may also contribute to the development of metabolic syndrome.

While this analysis provides valuable insights, it cannot establish direct causation. Nonetheless, the study underscores the importance of addressing perceived stress to reduce inflammation and the risk of metabolic syndrome. Stress-reduction techniques, such as mindfulness, relaxation exercises, and breathwork, could offer accessible, effective interventions to improve both mental and physical health.

Citation: Jurgens SM, Prieto S, Hayes JP. Inflammatory biomarkers link perceived stress with metabolic dysregulation. Brain Behav Immun Health. 2023 Oct 17;34:100696. doi: 10.1016/j.bbih.2023.100696. PMID: 37928770; PMCID: PMC10623170.

Key Points:

1. Cardiovascular Benefits: The review found that slow breathing can improve heart health by increasing heart rate variability (HRV) and reducing blood pressure. HRV is an important measure of heart health, reflecting the balance between stress and relaxation responses in the body. Slow breathing increased HRV both during and immediately after the practice, indicating better cardiovascular health and more activity from the calming parasympathetic nervous system.
2. Heart Rate and Blood Pressure: Although slow breathing didn’t immediately lower heart rate, it did lead to a slight reduction afterward, which is a positive sign for cardiovascular health. Additionally, systolic blood pressure (the top number in a blood pressure reading) dropped immediately after the practice and showed long-term improvements, particularly for people with prehypertension.
3. Emotional Benefits: Surprisingly, while there were improvements in negative emotions, they were only marginal. The researchers expected a bigger emotional benefit from slow breathing. However, the emotional and cardiovascular changes were still linked, as improvements in heart rate and HRV were associated with better emotional outcomes, though this relationship didn’t reach statistical significance.
4. Long-Term Effects: Although few studies focused on the long-term effects of slow breathing, the limited data suggested that the practice can lead to sustained improvements in blood pressure over time.

Conclusion:

The research highlights that slow breathing can be a simple and effective way to improve both heart health and emotional well-being. While the improvements in emotional states were modest, the physiological benefits for the heart were more pronounced. The study also suggests that the calming effect on the body may help create a positive feedback loop, where feeling physically calmer can support better emotional health.

Original Article Citation.   Shao, R., Man, I.S. and Lee, T., 2024. The Effect of Slow-Paced Breathing on Cardiovascular and Emotion Functions: A Meta-Analysis and Systematic Review. Mindfulness, pp.1-18.