Health Capsules

Sleep trackers and clinical sleep studies serve different purposes in understanding rest, fatigue, and possible sleep disorders. Readers will learn how consumer devices estimate patterns, how laboratory studies measure sleep and support diagnosis, and how to judge when self-tracking is sufficient versus when professional assessment is warranted.

Salt and health guidelines depend on how sodium intake is measured, how individual biology affects salt sensitivity, and how population policies translate evidence into recommendations. Readers will understand the main sources of disagreement behind sodium targets, including measurement uncertainty, genetic variation, and the record of public health interventions.