What role does LCT play in sleep?

The LCT gene encodes lactase, the enzyme that digests lactose (milk sugar). There is no direct, well-established scientific link between LCT variants and sleep quality. Indirectly, lactose intolerance symptoms—bloating, abdominal pain, diarrhea—can disrupt sleep if dairy is consumed close to bedtime. However, evidence is weak and based on anecdotal reports rather than controlled trials. Genetic tests for LCT polymorphisms (e.g., rs4988235) indicate likelihood of lactose intolerance, but they do not predict sleep issues. If you experience sleep disturbances, consider other factors like stress, sleep hygiene, or medical conditions. Caveat: no direct gene-sleep connection; focus on symptom tracking and dietary adjustments.