By SupplementenscannerHow we compare
Iron: the compound weight, the elemental figure, and which one compares
The official advice names iron only where a blood test shows a shortage. An iron pack may print the compound and its weight (ferrous sulfate, ferrous fumarate or iron bisglycinate, in milligrams), the elemental iron in milligrams, or both. Only the elemental figure is comparable from one tub to the next, because each compound carries a different share of iron in the same weight. A tub that prints the compound weight alone leaves you without a number to line up. What each form is, and how it is written on a pack, is set out on iron.
Folic acid: 400 micrograms, 5 mg and the folate spelling
The folic acid category ranks every folic acid product in one per-capsule list; three kinds sit in it, and telling them apart is your job. A 400 microgram tablet is one kind. A 5 mg tablet holds twelve and a half times as much, which the same advice mentions for some people, on prescription. And a product labelled folate, methylfolate or 5-MTHF is another form, with a dose that may be printed in micrograms or in micrograms DFE. Match the form and the dose first; only then does the per-capsule price mean anything.
NHS advice attaches a period to folic acid and runs vitamin D through the pregnancy. Nothing under Bronnen prints a stop date for a prenatal multi; a tub bought for the third trimester states in its ingredients whether folic acid is still in it, and at what dose.
Vitamin D3: one figure, two units
A vitamin D3 pack prints its dose in micrograms and often in IU as well; 10 micrograms is 400 IU. Read whichever unit both packs share, match the figure, and only then set the prices side by side. Drops are another case: the dose is per drop, and the bottle price says nothing until the drops per bottle and the micrograms per drop are known.
Prenatal multi or general multi: the line that decides
A prenatal multivitamin has a category of its own, apart from the general multivitamin. NHS guidance puts vitamin A in one sentence: "Do not take cod liver oil or supplements containing vitamin A (retinol)". Whether a given tub contains it is checked in its ingredient list, not on the front of the pack: the words are retinol and retinyl acetate, while beta-carotene is a separate entry and not the same thing.
Three further facts decide whether a multi can be set against loose tubs. How many pieces make up a day: a low price for each piece, taken twice a day, is a higher price per day than it looks. Whether the folic acid inside is folic acid or methylfolate, which matters as much here as it does in a single-ingredient tub. And whether DHA is in the tablet, in a capsule of its own, or not included at all. The label words are explained in our guide to reading a supplement label (in Dutch).
DHA, calcium, iodine, probiotics and choline: the figures kept off the front
Supplementscanner compares each of these on price per capsule; the pack figure to match first is what changes. For omega-3 it is DHA, printed apart from EPA: a fish oil lists both, in a ratio of its own, while an algae oil puts nearly all of its omega-3 into DHA. The line-by-line reading is in our fish oil guide (in Dutch). For calcium it is elemental calcium in milligrams. For probiotics it is the strains named and the CFU count.
Iodine and choline have no category of their own and are compared on pack price: iodine, as potassium iodide or kelp, with micrograms of iodine per unit, and choline, where the milligrams to read are choline itself rather than choline bitartrate, a heavier salt. Gummies and chewables print a dose per piece and are compared per piece on the same figures. For the months after the birth, the same ingredients return on breastfeeding.