How are Insulin and Schlaf related?

The relationship between insulin and sleep is bidirectional and clinically significant. Sleep deprivation or poor sleep quality (e.g., due to sleep apnea, shift work) consistently reduces insulin sensitivity and elevates fasting glucose, even in healthy individuals – well-documented in controlled human studies (e.g., Spiegel et al.). Conversely, insulin affects sleep: hypoglycemia can cause nocturnal awakenings, while hyperinsulinemia may disrupt melatonin production. Circadian rhythm genes like MTNR1B (melatonin receptor) are linked to impaired glucose tolerance. Caveat: individual variability is high; consumer DNA tests for this topic typically have small effect sizes and are not diagnostic. Anyone with sleep or metabolic concerns should consult a physician.