Sleep deprivation can trigger inflammation and hormone fluctuations, and affect blood glucose management (study), which can lead to breakouts. Look into under-diagnosed sleep conditions such as sleep apnea. Irregular sleep patterns can disrupt circadian rhythms and hormonal balances, potentially exacerbating acne breakouts.
Sleep tracking capabilities on devices such as the Oura ring, and Apple Watch may be useful in this scenario, especially if abnormal sleep is suspected.
Schrom, K. P., Ahsanuddin, S., Baechtold, M., Tripathi, R., Ramser, A., & Baron, E. (2019). Acne Severity and Sleep Quality in Adults. Clocks & sleep, 1(4), 510–516. https://doi.org/10.3390/clockssleep1040039
"Conclusion: Acne is highly associated with poor sleep and mood. Dermatologists are advised to attend closely to the psychological impact of acne. Improvements in sleep and mood may benefit the treatment of acne."
Zhu, Jiangting et al. “Sleep quality, circadian preferences, and mood among patients with acne vulgaris: a case-control study.” Sleep & breathing = Schlaf & Atmung vol. 27,5 (2023): 1997-2003. doi:10.1007/s11325-023-02777-5(edited)
"Mouthbreathing, increased lip separation and decreased upper lip coverage at rest were all associated with higher levels of plaque and gingival inflammation"
Wagaiyu, E G, and F P Ashley. “Mouthbreathing, lip seal and upper lip coverage and their relationship with gingival inflammation in 11-14 year-old schoolchildren.” Journal of clinical periodontology vol. 18,9 (1991): 698-702. doi:10.1111/j.1600-051x.1991.tb00112.x
"Conclusions: Mouth-taping during sleep improved snoring and the severity of sleep apnea in mouth-breathers with mild OSA, with AHI and SI being reduced by about half. The higher the level of baseline AHI and SI, the greater the improvement was shown after mouth-taping. Mouth-taping could be an alternative treatment in patients with mild OSA before turning to CPAP therapy or surgical intervention."
Lee, Y. C., Lu, C. T., Cheng, W. N., & Li, H. Y. (2022). The Impact of Mouth-Taping in Mouth-Breathers with Mild Obstructive Sleep Apnea: A Preliminary Study. Healthcare (Basel, Switzerland), 10(9), 1755. https://doi.org/10.3390/healthcare10091755(edited)