Introduction Sleep plays a crucial role in human health, not only for rest and alertness but also in regulating metabolic, hormonal, and cardiovascular processes. Recent studies have shown that sleep duration, quality, and timing are closely linked to the risk of type 2 diabetes, making adequate sleep a modifiable factor for diabetes prevention. Sleep Duration • There is a U-shaped association between sleep duration and type 2 diabetes risk. • Lowest risk: around 7 hours per night. • Short sleep (<6h) or long sleep (>9h) → risk increase up to 50%, including progression from prediabetes. Sleep Quality • Defined as overall satisfaction with all aspects of the sleep experience. • Poor sleep quality → 40% increased risk of developing type 2 diabetes. Chronotype / Sleep Timing • Evening preference (going to bed late, waking up late) → 2.5× higher odds of type 2 diabetes compared to morning types (early sleep/wake), independent of sleep duration and sufficiency. Physiological Importance of Sleep • Sleep modulates metabolic, endocrine, and cardiovascular processes. • Adequate sleep is a key modifiable risk factor and an essential part of diabetes prevention. Dr Miaad Adnan Al-Mustaqbal University The First University in Iraq