Short answer: Your all-in-one says 5,000 IU vitamin D and only 400 mg calcium because vitamin D is measured in micrograms and calcium is measured in grams. 5,000 IU of vitamin D weighs just 0.125 mg — it disappears into a scoop. A full 1,300 mg day of calcium would eat a third of that same scoop. So brands max out the cheap, featherweight nutrients for a big number on the label and sprinkle a token dose of the bulky, expensive ones. That's fairy dusting. The fix isn't a longer ingredient list — it's a shorter, honest one. At Rebuilt we built Pure Greens around exactly 13 ingredients in an 11 g scoop, with every gram printed on the label, so you can see what you're actually getting instead of guessing.
Why does my multivitamin have 5,000 IU of vitamin D but only 400 mg of calcium?
Because the two nutrients live on completely different scales.
Vitamin D is a fat-soluble micronutrient. Your Daily Value is 20 mcg — that's 800 IU. A "high dose" of 5,000 IU is 125 mcg, or 0.125 mg. In an 11 g scoop, that is roughly 0.001% of the powder. It costs a fraction of a cent and takes up no room at all.
Calcium is a macromineral. The Daily Value is 1,300 mg. And you can't put "calcium" in a tub — you put in a calcium salt. Calcium carbonate is about 40% elemental calcium, so a full day's dose needs about 2,500 mg of raw powder. Calcium citrate is about 21% elemental, so you'd need close to 4,800 mg. That's nearly half an 11 g scoop for one mineral, before you add anything else.
So the label reads 625% DV vitamin D and 31% DV calcium. Not because the formulator thinks you need six times the vitamin D. Because one nutrient is free real estate and the other one isn't.
What does a "big number" on a supplement label actually weigh?
- Vitamin D 5,000 IU = 0.125 mg
- Vitamin B12 500 mcg = 0.5 mg (and the DV is 2.4 mcg)
- Biotin 10,000 mcg = 10 mg
- Vitamin C 1,000 mg = 1 g — starting to get real
- Calcium 1,300 mg elemental = 2,500–4,800 mg of powder
- Magnesium 420 mg elemental = about 3,000 mg of magnesium glycinate (roughly 14% elemental)
- Potassium 4,700 mg = not happening in any scoop, ever
Once you see the weights, the label stops being impressive and starts being readable.
What is "fairy dusting" in supplements — and how do you spot it?
Fairy dusting is adding an ingredient in an amount too small to do anything, purely so it can appear on the label. It's legal. It's common. And it's the entire business model behind those 75-ingredient tubs.
The tells are consistent:
- A long ingredient list crammed into a small scoop — 50+ ingredients in 8–12 g is arithmetically impossible at meaningful doses.
- A proprietary blend: ten ingredients, one combined weight, no individual amounts. You cannot verify anything.
- Hero ingredients listed last. Order is by weight, so last means least.
- Percentages only where they flatter — big %DV numbers on the cheap vitamins, silence on the minerals.
- "Proprietary" used as a reason not to tell you. Transparency isn't a trade secret. It's a choice.
This is the part of the category we got tired of at Rebuilt. A scoop is a fixed budget. Every ingredient you add takes grams from another. Thirteen ingredients at real weights beats seventy at trace weights — and you can check our math on the label.
Which nutrients almost always get a full dose?
The light ones and the cheap ones:
- Vitamin D, B12, folate, biotin, vitamin K — measured in micrograms. Full doses are trivial.
- B-complex vitamins — milligrams, low cost, and they turn urine bright yellow, which many people read as "it's working."
- Vitamin C and zinc — cheap enough to dose properly.
- Vitamin E and selenium — small weights, easy wins.
And the ones that almost never do: calcium, magnesium, potassium, omega-3s, fiber, collagen, creatine, protein, and most standardized botanical extracts. All bulky, expensive, or both. If a single tub claims to cover all of those plus a multivitamin, the doses are decorative.
7 ways to tell a full dose from fairy dust
1. Convert IU to mg or mcg before you judge it
5,000 IU sounds ten times bigger than 500 mg. It's 4,000 times smaller. Do the conversion first: vitamin D IU ÷ 40 = mcg. Any number that looks huge in IU or mcg is a featherweight nutrient.
2. Read elemental weight, not compound weight
"Magnesium citrate 500 mg" is not 500 mg of magnesium — it's about 80 mg elemental. Good labels print both: "Magnesium (as magnesium bisglycinate) 200 mg." If a label only gives the compound weight, assume the elemental number is 5–6x lower. This one trick reveals most mineral fairy dusting instantly, and it matters if you're leaning on magnesium in the evening — worth reading alongside why you sleep better after a hot shower but wake up at 3 AM.
3. Do the scoop math
Take the serving size in grams. Add up every listed amount. Whatever's left is the unlisted remainder — flavoring, fillers, or trace ingredients. In an 11 g scoop, if the listed nutrients total 800 mg, you have 10.2 g of something the label isn't itemizing. Ask what it is.
4. Treat every proprietary blend as an unknown dose
Not a small dose. An unknown one. "Greens Blend 4,500 mg" could be 4,400 mg of cheap grass powder and 100 mg spread across nine others. Assume the worst until proven otherwise — that's what the format is designed to hide.
5. Compare against %DV, then against the research dose
%DV tells you what regulators consider a full day. Research doses are separate and often higher. Spirulina, for example, has been studied at gram-level daily doses — not the 50 mg a crowded blend can spare. In one randomized trial, spirulina supplementation supported reduced feelings of mental and physical fatigue.1 A trace amount isn't a small version of that. It's a different thing entirely.
6. Count ingredients against scoop size
Divide grams by ingredients. An 11 g scoop across 13 ingredients averages roughly 850 mg each — room for real amounts. The same 11 g across 60 ingredients averages 180 mg, and the first three ingredients will take most of that anyway. This is the single fastest filter in the category, and it's exactly why Rebuilt capped Pure Greens at 13.
7. Stack the bulky minerals separately
Stop expecting one scoop to be your calcium, magnesium, potassium and omega-3 source. It physically can't be. Get calcium from dairy, tinned fish or fortified foods. Get potassium from potatoes, beans and bananas. Add fermented foods — Stanford researchers found a 10-week high-fermented-food diet increased microbiome diversity and reduced markers of inflammation.2 Then use a greens powder for what it's genuinely good at: concentrated plant nutrition on days your food isn't perfect. If low energy is your actual complaint, start with the nutritional causes behind energy slumps before you buy anything.
How does Rebuilt Pure Greens handle the dose problem?
By refusing to play the number game. Pure Greens contains exactly 13 ingredients in an 11 g scoop. Danish-developed, fully transparent on the label, and no subscription lock-in — you buy it when you want it. We'd rather lose a spec-sheet comparison than sell you sixty ingredients you can't verify.
We're also straight about what it isn't. Pure Greens is not your calcium supplement. It's not your protein. It doesn't pretend to be a multivitamin. It's a concentrated greens blend, dosed at weights we're willing to print.
| What you're comparing | Rebuilt Pure Greens | Typical 50+ ingredient all-in-one |
|---|---|---|
| Ingredient count | Exactly 13 — Danish-developed, every gram on the label | Often 40–75; individual amounts frequently not disclosed |
| Serving size | 11 g scoop | Varies, commonly 8–12 g |
| Average grams per ingredient | Roughly 850 mg | Roughly 150–250 mg, unevenly distributed |
| Proprietary blends | None | Common |
| Purchase terms | No subscription lock-in | Varies; often subscription-gated pricing |
| Price transparency | Per-serving price visible on the product page | Varies by brand |
The Rebuilt Pure Greens promise, in one list:
- Exactly 13 ingredients — no filler roster
- 11 g per scoop, fully itemized
- Danish-developed and transparent by default
- No subscription lock-in, ever
Ready to stop decoding labels? Shop Pure Greens at Rebuilt — 13 ingredients, 11 g, nothing hidden.
What should you do if you're already taking a fairy-dusted all-in-one?
Don't panic and don't bin it. Work through it in order:
- Photograph the label and run tips 1, 2 and 3 on it.
- Identify the two or three nutrients you actually need at full dose.
- Cover those from food first, then from single-ingredient products.
- Keep the all-in-one only if it's doing something real at a real weight.
If your motivation for the tub was digestive comfort rather than nutrition, the dose question matters less than the ingredient question — our guide to why your stomach feels bloated and how to find relief covers that properly.
Where can you buy Pure Greens and the rest of the Rebuilt range?
Everything is at rebuiltperformance.com. Pure Greens sits on its own product page with the full 13-ingredient breakdown and the 11 g serving printed in plain sight — check it before you buy, that's the point.
What you get from Rebuilt:
- Labels you can read without a calculator
- No subscription traps — order when you want it
- Clean, natural ingredients you can trust
- A knowledge base that tells you when not to buy something
Build the habit that lasts. REBUILT THROUGH WORK.
Frequently asked questions
Is 5,000 IU of vitamin D too much?
It's 625% of the Daily Value. Many people tolerate it fine, but vitamin D is fat-soluble and accumulates, so it isn't a nutrient to stack blindly across three products. Check your total across everything you take and ask your doctor for a blood test if you're unsure.
Why can't a greens powder contain a full dose of calcium?
Physics. A full 1,300 mg of elemental calcium requires 2,500–4,800 mg of calcium salt depending on the form. In an 11 g scoop that's 23–44% of the entire serving for one mineral — leaving almost nothing for the greens you bought it for.
Does a higher ingredient count mean a better supplement?
Usually the opposite. Scoop size is fixed, so more ingredients means smaller amounts of each. Divide the serving weight by the ingredient count — if the average is under 200 mg, most of that list is there for the label, not for you.
What's the difference between a proprietary blend and a transparent label?
A transparent label lists an amount next to every ingredient. A proprietary blend gives one total for a group, so a brand can lead with an expensive ingredient and include almost none of it. Rebuilt doesn't use proprietary blends.
Does spirulina need a large dose to matter?
The research uses gram-level daily doses, not trace amounts. Trials have linked spirulina supplementation to reduced oxidative stress markers and improved endurance performance,3 and to improved self-reported sleep quality and stress levels.4 A 50 mg sprinkle doesn't replicate that.
I'm on a GLP-1 medication — does dosing matter more for me?
Yes, because your total food intake drops and nutrient density becomes the priority. Reduced intake during GLP-1 treatment is associated with digestive side effects including constipation and bloating, and dietary quality is a recognized part of managing it.5 Current nutrition guidance emphasizes protein, fiber and micronutrient adequacy during treatment.6 Fairy-dusted tubs are a poor fit here — you need real amounts, not a long list.
Should I take minerals at a different time than my greens powder?
It's often practical. Calcium can compete with iron and zinc for absorption, and many people prefer magnesium in the evening. Travel adds another layer — see why you sleep better on the plane than in your own bed after landing for how hydration and minerals shift on the road.
Claims overview
- Spirulina: supports normal energy levels and helps reduce feelings of mental and physical fatigue — randomized controlled trial, PMID:26888417.
- Fermented foods: support microbiome diversity — Wastyk et al. (2021), Stanford University.
- Spirulina: supports the body's normal defense against oxidative stress and supports exercise endurance — Kalafati et al. (2010), PMID:19936191.
- Spirulina: supports sleep quality and normal stress response — randomized controlled trial, PMID:34107141.
- Dietary supplement and dietary considerations during GLP-1 receptor agonist use — PMC9821052.
- Nutrition during GLP-1 treatment — Mozaffarian et al. (2025).
Daily Value figures referenced are US FDA Daily Values for adults. Elemental mineral percentages reflect standard compound composition. Structure/function claims above are tied to the named ingredient, not to any specific product's ability to affect a disease.
References
- Wastyk HC, et al. Gut-microbiota-targeted diets modulate human immune status. Cell. 2021;184(16):4137. PMID:34256014.
- Kalafati M, et al. Ergogenic and antioxidant effects of spirulina supplementation in humans. Med Sci Sports Exerc. 2010. PMID:19936191.
- Randomized controlled trial on spirulina supplementation and mental and physical fatigue. PMID:26888417.
- Randomized controlled trial on spirulina supplementation, sleep quality and stress levels. PMID:34107141.
- GLP-1 receptor agonists: gastrointestinal side effects including constipation and bloating, and dietary supplement considerations. PMC9821052.
- Mozaffarian D, et al. Nutrition during GLP-1 treatment. Am J Clin Nutr. 2025;122:344.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Article is ready to paste into Shopify at `/blogs/knowledge-base/why-does-my-all-in-one-supplement-say`. ~1,850 words, 7 numbered tips, 7 FAQs with matching FAQPage schema, 3 internal links with keyword anchors, one comparison table, Pure Greens facts held at exactly 13 ingredients / 11 g throughout, and the FDA disclaimer verbatim at the end.
