The reading room.
Clear explanations for the questions that come up in the supplement aisle. Start with a topic, a label, or a comparison.
8 guides to explore
A closer look at magnesium citrate
Nature Made, NOW, and Life Extension compared by serving size, elemental magnesium, capsule count, and cost.
Read the guideCitrate or glycinate?
Look beyond the form name to elemental magnesium, serving size, tolerance, and the limits of health claims.
Read the guideVitamin D2 vs. D3
Understand the two forms, convert micrograms and IU, and compare products without assuming more is better.
Read the guideUnderstanding magnesium
A plain-language starting point for magnesium intake, elemental amounts, and questions to bring to your clinician.
Read the guideUnderstanding vitamin D
A clear explanation of vitamin D units, total intake, and the difference between a general guide and individual treatment.
Read the guideWhat an omega-3 label really tells you
Why the total fish oil amount is different from EPA plus DHA, and how to compare omega-3 labels fairly.
Read the guideStart with the label
Serving size, ingredient amounts, Daily Value, other ingredients, quality claims, and the details to check before buying.
Read the guideThe price tag is only the beginning
A simple calculation that makes bottle prices more useful, with worked examples and common comparison traps.
Read the guide