circadian rhythm

1 entry tagged circadian rhythm. All writing.

SEPTEMBER 22, 2026 Does Light at Night Hurt Your Heart? A UK Biobank study of 11,071 adults found that people with bedroom light above roughly 3 lux at night — dimmer than almost any lamp, but bright enough for closed eyes to register — developed a thicker, stiffer-pumping heart and higher rates of heart failure, stroke and atrial fibrillation years later than people who slept in real darkness. Led by Tulane's Lu Qi, published September 9, 2026 in the European Heart Journal. Here's what "3 lux" actually looks like, and what the study can and can't say about a nightstand lamp.

Medical disclaimer. Everything on this site is general information for education only. It is not medical, nutritional or health advice, and it is not a substitute for advice from a licensed physician, pharmacist, dietitian or other qualified health professional who knows you. The author is not a licensed health professional and writes under a pen name; no entry has been reviewed by a doctor or anyone else with a medical licence. Reading this site, or writing to it, creates no doctor–patient or other professional relationship. Do not start, stop or change any medication, supplement, diet or treatment because of something read here — talk to your clinician first. If you think you may have a medical emergency, call your doctor or your local emergency number (911 in the United States) now. Read the full disclaimer →