I always ask my patients how they sleep. Not out of courtesy, but because sleep is one of the most underrated determinants of health — and one of the most neglected in modern medicine.
For a long time, sleep was seen as wasted time. We now know the opposite is true: sleep is an active biological process during which the brain consolidates memories, regulates hormones and clears metabolic waste. The discovery of the glymphatic system showed that it is largely during deep sleep that the brain «washes» away proteins associated with Alzheimer’s disease.
Chronic sleep deprivation is no minor inconvenience. It is associated with a higher risk of obesity, type 2 diabetes, hypertension, depression and all-cause mortality. A single poor night is enough to impair insulin sensitivity and disturb appetite the following day — something many of my patients recognise at once.
In my practice, working on sleep is often the first step, not the last. Regular hours, morning daylight exposure, fewer screens at night and a cool, dark bedroom are simple interventions, free of side effects and deeply effective. Sleeping well is not a luxury: it is preventive medicine in its purest form.
Selected references
Xie L, et al. Sleep drives metabolite clearance from the adult brain. Science. 2013;342(6156):373–377.
Cappuccio FP, et al. Sleep duration and all-cause mortality: a systematic review and meta-analysis. Sleep. 2010;33(5):585–592.
Spiegel K, Tasali E, Penev P, Van Cauter E. Brief communication: sleep curtailment and impaired glucose tolerance. Ann Intern Med. 2004;141(11):846–850.
