7 Hours and 18 Minutes of Sleep Improves Insulin Resistance

A cross-sectional analysis of over 23,000 adults found that sleeping approximately 7 hours and 18 minutes per night may be optimal for improving estimated glucose disposal rate (eGDR), a marker of insulin resistance and a primary driver of type 2 diabetes (T2D).¹

The study, published in BMJ Open Diabetes Research & Care, also determined that weekend catch-up sleep has differential effects on glucose metabolism, depending on whether individuals sleep above or below the optimal threshold during the week. The results offer new insights into the health benefits of adequate sleep and personalized sleep recommendations for individual patients.¹

Key Findings

The analysis revealed an inverted U-shaped curve between weekday sleep duration and eGDR, with the optimal threshold at 7 hours and 18 minutes. Below this threshold, increased nightly sleep was associated with higher eGDR, indicating improved insulin sensitivity (β-coefficient = 0.273; 95% CI, 0.224-0.322; P < .001). Above this threshold, more nightly sleep was associated with lower eGDR (β-coefficient = −0.222; 95% CI, −0.272 to –0.171; P < .001), particularly among women and adults aged 40 to 59 years.¹

For individuals sleeping less than the optimal threshold during the week, 1 to 2 hours of weekend catch-up (WCS) sleep was associated with higher eGDR compared with no catch-up sleep. However, for those sleeping more than the optimal weekday threshold, more than 2 hours of WCS was associated with lower eGDR after accounting for lifestyle factors, ethnicity, marital status, and educational attainment.¹

Following a moderation analysis, the investigators found that, despite the noted benefits when weekday sleep was lacking, WCS offered no statistically significant moderation toward the association between weekday sleep duration and eGDR (β = 0.003; P = .438). Overall, the authors suggest that excessive WCS is not recommended for optimal health outcomes.¹

Bidirectional Relationship Between Sleep and Metabolism

The study authors emphasized that sleep and metabolic health influence each other bidirectionally. Poor glycemic status has been linked to a higher likelihood of both short and extended sleep durations, as well as sleep disorders. This creates a potential cycle wherein metabolic dysregulation disrupts normal sleep patterns, and abnormal sleep further aggravates metabolic health.¹

Experimental studies have demonstrated that partial sleep deprivation induces insulin resistance through multiple metabolic pathways. A single night of partial sleep restriction decreased glucose disposal rate during hyperinsulinemic clamp studies by approximately 20%, reflecting decreased peripheral insulin sensitivity. Another study found that sleep restriction for a 1-week period reduced insulin sensitivity by approximately 11% to 20% without significant alterations in insulin secretory response. These physiological changes may contribute to variations in glucose regulation, particularly in patients with type 1 diabetes and T2D.^2,3

Clinical Guidelines, Recommendations, and Pharmacist Implications

The American Diabetes Association and European Association for the Study of Diabetes consensus guidelines now highlight sleep as a central component in the management of prediabetes and T2D, placing it on the same level as other lifestyle behaviors such as physical activity and nutrition. General guidelines recommend at least 7 hours of sleep per night regularly for optimal health, although specific recommendations for those living with T2D have not been developed.^4,5

Pharmacists play important roles in counseling patients about sleep hygiene and its impact on diabetes risk and management. Pharmacists should be educating patients with T2D about the U-shaped relationship between sleep duration and insulin resistance, emphasizing that both insufficient and excessive sleep may increase diabetes risk. They can also discuss guidance on sleep hygiene practices, including maintaining consistent sleep-wake schedules, limiting caffeine and alcohol in the evening, avoiding large meals before bed, and creating optimal bedroom environments.

Patients experiencing sleep disturbances should be referred to health care providers for evaluation and, if indicated, to sleep specialists. Treating sleep disorders (eg, obstructive sleep apnea) in patients with diabetes has been shown to improve nighttime glucose levels and insulin sensitivity. The severity of untreated sleep apnea directly correlates with poorer glucose control in patients with T2D.⁶

Study Limitations

The authors acknowledged several limitations. As an observational study, it cannot establish causal relationships, and reverse causation is possible, whereby disrupted glucose metabolism may interfere with sleep, rather than the other way around. The study relied on self-reported data on sleep duration, which may not be accurate. Additionally, researchers could not adjust for all potential confounders, such as sleep quality, which could have led to residual confounding.¹

Despite these limitations, the findings suggest that sleep patterns, particularly WCS, may be relevant for metabolic regulation in diabetes and could inform considerations for health care professionals in managing patient care. Future research should investigate whether interventions aimed at optimizing sleep duration may be beneficial in stabilizing glucose levels and reducing diabetes risk.¹

REFERENCES

1. Fan Z, Wei R, Chen T, et al. Association of weekday sleep duration and estimated glucose disposal rate: the role of weekend catch-up sleep. BMJ Open Diabetes Res Care. 2026;14(2):e005692. doi:10.1136/bmjdrc-2025-005692

2. Donga E, van Dijk M, van Dijk JG, et al. A single night of partial sleep deprivation induces insulin resistance in multiple metabolic pathways in healthy subjects. J Clin Endocrinol Metab. 2010;95(6):2963-2968. doi:10.1210/jc.2009-2430

3. Buxton OM, Pavlova M, Reid EW, Wang W, Simonson DC, Adler GK. Sleep restriction for 1 week reduces insulin sensitivity in healthy men. Diabetes. 2010;59(9):2126-2133. doi:10.2337/db09-0699

4. American Diabetes Association Professional Practice Committee. 3. Prevention or delay of diabetes and associated comorbidities: standards of Care in Diabetes—2025. Diabetes Care. 2025;48(1 suppl 1):S50-S58. doi:10.2337/dc25-S003

5. Henson J, Covenant A, Hall AP, et al. Waking up to the importance of sleep in type 2 diabetes management: a narrative review. Diabetes Care. 2024;47(3):331-343. doi:10.2337/dci23-0037

6. Patients with type 2 diabetes or hypertension must be evaluated for sleep apnea. News release. American Academy of Sleep Medicine. June 3, 2013. Accessed March 9, 2026. https://aasm.org/patients-with-type-2-diabetes-or-hypertension-must-be-evaluated-for-sleep-apnea/#