Sleep
The latest from Sleep on Vitalspell.
GLP-1 receptor agonists reduce sleep apnea severity by 14 events per hour
A 2026 meta-analysis of four randomized controlled trials finds that GLP-1 receptor agonists reduce the apnea-hypopnea index by 13.9 events per hour, lower body weight by 12.5 kg, and improve blood pressure in patients with obstructive sleep apnea and obesity.
Magnesium L-threonate improved cognition by 7.5 cognitive years in 6-week trial
A 6-week randomised trial in 100 adults found that 2 grams per day of magnesium L-threonate (Magtein) improved overall cognitive performance and reduced estimated brain cognitive age by 7.5 years. Sleep improvements were selective, but heart rate and heart rate variability both moved in favourable directions.
Exercise and sleep interventions show synergistic effects on cardiometabolic health in 8-week trial
A 2026 randomized trial found that combining high-intensity circuit training with a digital sleep health intervention produced greater improvements in sleep efficiency, wake after sleep onset, and cardiometabolic markers than either intervention alone in sedentary young women.
Magnesium and sleep: what the evidence says about the most recommended bedtime supplement
Magnesium has a plausible mechanism for improving sleep through GABA and NMDA receptors, but the trial data shows the effect is modest and largely limited to people with low dietary magnesium intake.
Caffeine within 12 hours of bedtime harms sleep, often without you noticing
A randomized crossover trial in Sleep found that 400 mg of caffeine disrupts sleep when consumed within 12 hours of bedtime, while 100 mg is safe up to four hours before bed. Most participants could not tell when caffeine was harming their sleep.
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Nutrition timing alone not enough for night-shift metabolic health, trial finds
An 8-week crossover trial in female healthcare workers found that protein-and-nutrient-timing guidance modestly improved visceral fat percentage but did not shift inflammatory markers, gut microbiome diversity, or mental health scores. The findings suggest dietary changes alone are insufficient to reverse the metabolic effects of circadian disruption.
What Experts Want You to Know About High-Carb Fueling
Pro athletes and brands are pushing 120 grams of carbs per hour during racing. The science says no peer-reviewed study supports a benefit above 90 grams, and overshooting may hurt amateur performance while stressing the gut.