What dietary factor has contributed to Jack's edema?

High-sodium meals contribute to edema due to the way sodium impacts fluid balance in the body. When there is an increase in sodium intake, the body tends to retain water to balance out the electrolytic concentration in the bloodstream, leading to an increase in extracellular fluid. This retention can manifest as swelling or edema, particularly in areas like the legs or abdomen, as the excess fluid accumulates in tissues.

In contrast, low-protein meals typically do not directly cause edema; they might lead to a different issue of protein-deficiency disorders, which might cause edema later due to a lack of albumin and other proteins that help keep fluid within blood vessels. Low-carbohydrate and high-fiber meals are generally associated with other metabolic impacts but are not known to directly lead to edema. Overall, the direct relationship between high sodium intake and fluid retention makes the consumption of high-sodium meals a clear dietary factor contributing to Jack's edema.