Is HDL useful for sleep?

Whether HDL (high-density lipoprotein) is directly useful for sleep is not supported by strong evidence. HDL is best known for its cardiovascular protective role. Observational studies show that poor sleep—such as short duration or sleep apnea—is associated with lower HDL levels. However, causality remains unclear: does poor sleep lower HDL, or does low HDL impair sleep? No randomized controlled trials have demonstrated that raising HDL improves sleep quality or duration. The evidence is moderate at best, based on associations rather than interventional data. From a practical standpoint, focusing on sleep hygiene, regular exercise, and a balanced diet is more likely to benefit both HDL and sleep. Deliberately boosting HDL (e.g., via supplements) to improve sleep is not evidence-based. Caveat: low HDL (<40 mg/dL in men, <50 mg/dL in women) is a cardiovascular risk marker, but the overall lipid profile and lifestyle factors matter more.