The multivitamin is the most popular supplement in the world. It’s the default starting point for almost everyone who decides to “take something” — a single capsule that promises to cover all the bases. It’s also, in my professional experience, one of the categories where the gap between what people assume they’re getting and what’s actually in the bottle is widest.
I’ve reviewed a great many multivitamin formulations over 20 years in this industry. Rather than name specific brands — which creates legal complications and dates quickly — this article walks you through exactly how I assess a multivitamin, what I consistently find, and how you can audit your own in about five minutes. The patterns are remarkably consistent across the mass market.
“A multivitamin is 20-odd ingredients in one capsule. That’s 20 opportunities to use the cheap form. Most mass-market products take most of them.”
The fundamental tension in every multivitamin
Before the specifics, understand the structural problem. A multivitamin tries to fit a broad range of vitamins and minerals into one or two capsules at a price point that allows mass-market sale. That constraint forces compromises in three directions at once: the forms have to be cheap, the doses have to be small enough to fit, and minerals in particular can’t all be included at meaningful amounts because they’re physically bulky.
This means that even a well-intentioned multivitamin is working against real limitations. And a cost-optimised one stacks compromise on compromise. Understanding this tension is the key to reading the label realistically rather than hopefully.
How I audit a multivitamin — the five checks
The B vitamin forms
This is my first look, because it’s the fastest tell of overall quality. I check B12 and folate specifically. If B12 is cyanocobalamin (rather than methylcobalamin) and folate is folic acid (rather than methylfolate or 5-MTHF), the product is using the cheapest synthetic forms — the ones a significant share of people convert inefficiently. These two ingredients are a reliable proxy: a brand that economises here has usually economised everywhere.
The magnesium form and dose
Magnesium is bulky, so multivitamins rarely include a meaningful dose — and when they do include any, it’s almost always magnesium oxide, the least absorbable form. You’ll often see “Magnesium 50mg (as magnesium oxide)” — a small dose of a poorly absorbed form, contributing very little. This isn’t necessarily the manufacturer being cheap; it’s partly the physical constraint of the format. But it means your multivitamin is rarely a real source of magnesium, whatever the label implies.
Vitamin D form and amount
I check that it’s D3 (cholecalciferol) not D2, and I look at the IU. Many multivitamins contain 200–400 IU — a maintenance-level amount that’s unlikely to correct a deficiency. If you’re relying on your multivitamin for vitamin D and you live somewhere with real winters or work indoors, that dose is probably insufficient for your needs.
The mineral forms generally
Beyond magnesium, I scan how the other minerals are bound. “Oxide” and inorganic salt forms are cheaper and less absorbable; “citrate,” “glycinate,” “bisglycinate,” and chelated forms are better absorbed. Zinc oxide vs zinc citrate, for example. A multivitamin using chelated mineral forms throughout is a meaningfully higher-quality (and higher-cost) product than one defaulting to oxides.
The “proprietary blend” or fairy-dust additions
Many multivitamins add a flourish of trendy extras — “superfood blend,” “antioxidant complex,” herbal extracts — usually as a proprietary blend with undisclosed individual doses, almost always at amounts far too small to do anything. These exist to support marketing claims on the front, not to provide a functional dose. I treat them as decoration and ignore them in my assessment.
What I consistently find across the mass market
Running these five checks across typical supermarket and pharmacy multivitamins, the pattern is remarkably stable: synthetic B vitamin forms (cyanocobalamin, folic acid), token amounts of poorly-absorbed magnesium, maintenance-level or low vitamin D, oxide-form minerals, and a sprinkle of underdosed “extras” for the label. None of this makes these products dangerous. It makes them far less effective than their packaging implies.
A cheap multivitamin isn’t worthless — it provides a broad base of micronutrients that may genuinely help someone with a poor diet or specific gaps. But it’s rarely the efficient, comprehensive solution it’s marketed as. For most people, two or three well-chosen single supplements in the right forms — at the doses they actually need — deliver more real benefit than one multivitamin trying to do everything cheaply. The multivitamin’s appeal is convenience and reassurance, not optimal nutrition.
Higher-quality multivitamins do exist
To be fair to the category: there are well-formulated multivitamins that use active B vitamin forms, chelated minerals, D3 at meaningful doses, and disclose everything transparently. They cost considerably more, often require taking several capsules per day (because good forms at real doses don’t fit in one), and are sold by brands that compete on formulation rather than price. If you want a multivitamin, these are the ones worth paying for — and the five checks above will identify them quickly.
Audit your own in five minutes
Take your current multivitamin and run the checks: Is the B12 methylcobalamin or cyanocobalamin? Is folate methylfolate or folic acid? Is vitamin D listed as D3, and at what IU? Are the minerals chelated forms or oxides? Is there a proprietary blend hiding doses? Five questions. The answers will tell you whether you’re holding a thoughtfully formulated product or a cost-optimised one wearing confident packaging.
Don’t assume your multivitamin is doing what its label implies. Most mass-market products use the cheapest forms at modest doses across the board. If you take one, audit it with the five checks — and consider whether two or three targeted single supplements in the right forms might serve you better than one capsule trying to cover everything at the lowest possible cost.
Want me to run these checks on your actual multivitamin?
The Label Review audits exactly this — every ingredient, every form, every dose — and tells you whether your multivitamin is worth keeping or whether targeted singles would serve you better. Written report in 72 hours. Starts at €49.
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