The format of a supplement matters enormously. It shapes whether you actually take it, how easily it stacks with everything else, and whether your routine is something you can sustain. And above all, the format of a supplement can impact how well a supplement works for your body.

Researching iron made this concrete for me. It's never just about getting enough iron. It's about whether your body can absorb it. And absorption isn't shaped by the form of the mineral alone. It's shaped by everything that comes with it and everything around it. That puts the delivery system itself squarely in question.

Which brings me to gummies. They've been popular for years, but right now they're everywhere again, partly because of Grüns’ recent billion-dollar exit. There's a lot of money in supplements, and especially in gummy supplements. While Grüns is a supergreens gummy, other brands are pushing melatonin, magnesium, and increasingly creatine.

And I get the appeal. I love gummies. They're fun, they make supplements something to look forward to, they remind you of being a kid.

So here's my inevitable question. Can we really put anything we want into a gummy and expect it to work? Or are there trade-offs we should understand — about delivery systems in general, and the gummy format in particular — before we build our stack around them?

It depends entirely on what’s inside. The good news is that a gummy is a genuinely good way to take a few nutrients. The gummy format itself typically doesn’t block absorption. The real questions are whether the nutrient survives the processing that creating gummies requires as well as storage.

These two are the only ones with solid human proof.

In a head-to-head trial, a vitamin C gummy put just as much vitamin C into the blood as a tablet.

For vitamin D, the gummy actually beat the pill.

(Note: the vitamin C study was funded by the gummy's maker; the vitamin D one was not.)

Calcium clearly gets absorbed too — enough that a toddler reached vitamin-D and calcium toxicity from gummies. So the format itself can deliver.

B vitamins look reasonable too. They dissolve and release in the gut in lab tests.

And I’ll admit that I’m happy about the beginnings of creatine findings: a gummy improved performance in 32 women athletes, though no one has checked how much creatine the gummies actually held.

Trials are underway right now measuring the blood levels you'd actually absorb from iron, B12, folate, omega-3, magnesium, and creatine gummies. So hopefully, the next few years will give us more answers on which actually work via gummy delivery.

These have no gummy studies at all. There’s nothing that I can find published or registered for trials. They’re sold purely on the logic that because the nutrient works in a pill, it must work in a gummy.

Even if a gummy format works fine, you need to be getting enough to make a difference in your body.

Gummies are hard to dose precisely. When researchers tested 25 melatonin gummies, 88% had the wrong amount inside — anywhere from 74% to 347% of what the label promised.

They also degrade. Vitamin C breaks down as the gummy is cooked and while it sits on the shelf, so the amount drops over time. Vitamins are fragile and can break down without a protective coating, so the dose in month six isn't necessarily the dose on the label. How much you absorb can even depend on how thoroughly you chew.

Grüns ran a 12-week placebo-controlled trial in 120 adults that measured nutrients in the blood. (And let me tell you, even though it’s their own study, this is great. They’ve gone further than many brands to build something based on the science.)

It found folate up 20.5% and vitamin C up 40.1%. Those are two of the easiest, most water-soluble nutrients, so we’d expect positive findings for these two in particular. The study reports results for only those two, nothing for the other 27 ingredients.

🔍 Look for a USP or NSF seal on anything dose-sensitive. A third-party seal is a quick check that can catch a wrong amount.

📅 Buy vitamin C gummies in sizes you'll finish. Vitamin C fades inside the gummy over months, so skip the jumbo bottle, mind the expiry date, and keep them cool and dry.

🍬 Treat the sugar (or its replacement) as the real cost. Check the grams of sugar per serving before you buy, and remember a "serving" may be several gummies a day. This could be the real tradeoff you’re making.