Lifestyle
What you do during the day shapes how you sleep at night. These guides examine the everyday factors that help or hurt your rest — alcohol timing, caffeine half-life, evening exercise, diet, and screen habits. Each article connects the science to actionable changes you can try tonight.
Why Alcohol Disrupted Sleep Leads to a 3 AM Wake-Up Call
A nightcap makes you drowsy but wrecks your sleep stages. Here's how alcohol raises your heart rate, suppresses REM, and fragments the second half of your night.
How Much Deep Sleep Do You Need? What's Normal by Age — and How to Get More
How much deep sleep is normal, why it matters more than total hours, what reduces it, and how to measure your own deep sleep without a clinic.
REM, Deep, and Light Sleep — What Each Stage Does and How to Get More
A 5-minute primer on the four sleep stages: what REM, Deep, and Light each do for your body, how much you need, and how to track them on iPhone.
Why You're Still Tired After 8 Hours of Sleep (And How to See What's Actually Happening Tonight)
Eight hours in bed isn't restorative sleep. Seven evidence-based reasons you wake up exhausted — and how to collect your own sleep data tonight.