The meal tricks matter far less across a week of eating
The best and the worst single meal for iron absorption differ 4.4-fold. Compared across a diet eaten over two weeks, that gap falls to two-fold.
What the study found
Across a fortnight of meals, a 4.4-fold absorption gap shrinks to 2
The single meal built to help iron absorption most and the one built to block it most differ 4.4-fold. Run the comparison across a diet eaten over two weeks and the gap falls to two-fold. Which is why advice built on one test meal does not survive contact with a week of eating.
The caveat · The two-week figure is one study
This is a narrative review, so which studies went into it was the authors' judgement, and they work at the laboratory that produced much of the underlying isotope work. The two-week comparison rests on a single cited study. And single-meal effects are real, so this deflates the advice rather than cancelling it.