Nutrition.

5 clinician-reviewed articles in this topic.

Nutrition articles

Two vitamins doing overlapping work. Why testing one without the other can mask a deficiency that keeps progressing.

Mostly made in skin from sunlight rather than obtained from food. Why levels swing by season and who is worth testing.

Tightly regulated regardless of intake. Why a blood calcium result says little about your diet or your bones.

Ferritin, transferrin, serum iron and saturation describe different stages of the same process - and the pattern shows how far along it has gone.

Involved in hundreds of processes, and awkward to measure - serum testing captures only a small fraction of what your body holds.