The biology of daytime alertness - circadian rhythms, caffeine timing, nutrition basics - and what remains uncertain.
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An afternoon slump in concentration is not a personal failure. Controlled sleep research has observed a midday increase in sleep tendency in some groups, with timing and intensity that vary between people. Sleep loss, schedule mismatch, and meals can also affect how alert you feel.
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Magnesium glycinate, citrate, and oxide are marketed differently. This piece explains the biochemical differences, what limited evidence exists, and what questions remain unanswered.
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Why sleep quality varies, what the research actually shows, and practical questions to explore with a clinician.
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