A tester wears multiple smart rings, straps and watches side by side over many nights to check how accurately they measure heart rate, HRV and sleep. The newsletter also covers the psychology of over-relying on sleep scores, such as orthosomnia, and helps readers decide which devices are worth trusting.

Pediatric sleep physician Dr. Craig Canapari writes practical, evidence-based guidance on children's sleep, from toddler night wakings and sleep onset associations to infant feeding and teen screen-time rules. Readers get clear explanations of causes, specific fixes, and commentary on policy changes that affect children's sleep.

A London-based newsletter that turns human nutrition research into practical food advice for everyday problems like winter immunity, evening cortisol and afternoon tiredness. Each issue checks popular food claims against actual trial evidence, though some sections are behind a subscription paywall.

A practical, science-informed newsletter for readers over fifty on health, aging and daily life, covering topics like dizziness on standing, the emotional side of later-life health changes, and avoiding home repair scams. Each issue pairs an everyday scenario with citations to medical and government sources and concrete steps the reader can take.