From the desk
Micrograms are not milligrams
Micrograms are not milligrams. The difference is a factor of one thousand and it is one letter wide on a label. A botanical listed at 100 mcg is a ten-thousandth of a gram; the same botanical in the research is measured in hundreds of milligrams or in grams. This post is about how to read that difference, why an itemised panel is where you can finally see it, and what a 10:1 extract ratio does to the arithmetic.
The unit that hides in plain sight
Supplement panels use three units for weight and they look almost identical at eight-point type. g is a gram. mg is a milligram, a thousandth of a gram. mcg — sometimes written µg — is a microgram, a thousandth of a milligram and a millionth of a gram.
The step between mg and mcg is the one that matters commercially, because it is a factor of a thousand and it is invisible at a glance. A label saying 500 mg of an ingredient and a label saying 500 mcg of the same ingredient describe products that differ by three orders of magnitude, and they look the same from arm’s length in a shop.
| Written on a label | In grams | Roughly the weight of |
|---|---|---|
| 1 g | 1 | A raisin, or a paperclip |
| 500 mg | 0.5 | A large capsule's contents |
| 100 mg | 0.1 | A grain of rice |
| 7 mg | 0.007 | A grain of sand |
| 100 mcg | 0.0001 | A sixth of a grain of table salt |
There are ingredients where micrograms are exactly right. Vitamin D is dosed in micrograms — the adult RDA is 15 mcg — and so are vitamin B12, folate, biotin, iodine and selenium. A microgram figure on a vitamin line is normal. A microgram figure on a botanical extract line is the thing worth stopping at, because no botanical in the clinical literature is studied at that scale.
One habit worth building
When you look at a Supplement Facts panel, read the unit before you read the number. Most people do it the other way round, which is how “100” registers as a substantial figure before the “mcg” has been processed at all.
What a 10:1 extract actually means
Extract ratios appear on labels because they sound impressive, and they are genuinely useful information — just not in the direction most buyers assume.
A 10:1 extract means ten parts of raw plant material were processed down to one part of concentrate. So one milligram of a 10:1 extract was drawn from about ten milligrams of the original plant. Run that backwards on a label figure and you can work out the raw-plant equivalent, which is the number you can actually compare against a study that used dried herb.
| On the label | Raw plant equivalent | A typicalresearch amount for a men's botanical |
|---|---|---|
| 100 mcg | about 1 mg | hundreds of mg to several g |
| 10 mg | about 100 mg | hundreds of mg to several g |
| 100 mg | about 1 g | in range |
| 500 mg | about 5 g | comfortably in range |
The ratio does not rescue a microgram figure. Ten times a very small number is still a very small number, and a ratio without a marker content — the percentage of the compound the research is actually about — tells you about concentration rather than about activity. A 10:1 extract standardised to nothing in particular is a concentration claim, not a potency claim.
Three comparisons to keep in your head
Not to be memorised, just to have available when a number looks impressive.
A grain of table salt
About 0.6 mg. So a panel listing four botanicals at 100 mcg each has less botanical material in it, by weight, than a single grain of salt.
A standard capsule
A large gelatin capsule holds roughly 500 mg of powder. That is 5,000 times a 100 mcg figure, and it is the format most single-ingredient botanical supplements use.
A teaspoon of powder
About 3 g, which is 3,000 mg. This is the sort of amount the maca literature works with, and it is 30,000 times a 100 mcg label figure.
None of these is a criticism of any particular product. They are reference points, and the reason to carry them is that a Supplement Facts panel gives you a number without a scale, and a number without a scale is very easy to accept.
Why micro-dosing is legal and common
This is the part that surprises people, so it is worth being precise about it. Listing a botanical at 100 mcg breaks no rule. There is no minimum quantity for a dietary ingredient in the United States, no requirement that an ingredient be present at a researched dose, and no requirement that the label say how the amount compares to anything.
What the rules do require is that the amount be declared, and that is the part worth valuing. A panel that itemises 100 mcg is telling you the truth about a small amount. A proprietary blend that lists the same ingredient inside a combined total is telling you nothing at all, and the same ingredient could be at 100 mcg behind it without you ever knowing.
So there are two separate questions, and it helps to keep them apart. Is the panel honest? An itemised panel is more honest than a blend. Is the amount adequate? That is a different question with a different answer, and the itemised panel is what lets you ask it.
The uncomfortable corollary
The most transparent labels in this category are often the ones that reveal the least flattering formulas, because they are the only ones you can check. A product with a proprietary blend may contain even less and you would have no way to find out. Reward the transparency and judge the amount separately.
How to run the check in thirty seconds
Turn the bottle over
The front is design. The panel is the document.
Read the unit on every botanical line
mg or mcg. This is the whole trick and it takes five seconds.
Add the botanical lines together
One total, in milligrams. Convert any mcg figures by dividing by a thousand.
Note any extract ratio
At 10:1, multiply by ten for a raw-plant equivalent. At 4:1, by four. No ratio means no conversion is possible.
Compare against one number you already know
A 500 mg capsule. If the whole botanical content of a serving is a fraction of one capsule's contents, you have your answer.
Then look up one ingredient's studied dose
Two minutes at a government or hospital site. Ask what amount the trials used.
Six steps, no expertise, and it works on any bottle in any shop. The only thing it requires is reading the unit before the number.
What this means for the product we sell
Horse Fuel is the reason this post exists, and it would be dishonest to write nine hundred words about micrograms and then decline to apply them.
The Horse Fuel panel lists fenugreek, maca, tribulus and horny goat weed at 100 mcg each, all as 10:1 extracts. That is 0.4 mg of extract in total, representing roughly 4 mg of raw plant material across all four. A single 500 mg capsule of any one of them contains more than a thousand times as much.
The panel also does something most of its competitors do not: it prints those figures. Nothing is hidden behind a blend total, the extract ratios are given, and the plant part is named for three of the four. That is why our label transparency score for this product is 3 out of 5, the highest this desk has given, while its ingredient evidence score is 1.
Both of those things are true at once, and the reason you can know both is that somebody printed the number. The full label page has every row, and the ingredients page has the research amounts beside each one.
Where microgram doses come from
It is worth understanding why a formulator would put 100 micrograms of something into a product, because “to mislead people” is the least interesting explanation and usually not the main one.
Label presence
An ingredient on the panel can be named in the marketing. That is the commercial function of a small amount and it is entirely legal. The industry term is a label claim: the ingredient is there so the name can be used.
Format constraints
A gummy is mostly sugar matrix and it can only carry so much active material before it stops setting, tastes bitter or turns to grit. Real botanical doses in grams simply do not fit in a chewable, which is why gummy versions of herbal products are almost always micro-dosed.
Cost
Concentrated botanical extract is not free, and four ingredients at researched doses would multiply the cost of goods many times over. A hundred micrograms costs effectively nothing.
Caution, occasionally
Sometimes a formulator keeps an amount low because the ingredient has interactions at real doses. On this panel fenugreek has a long do-not-take list at researched amounts, and at 100 micrograms none of it applies.
The first three explain nearly every microgram botanical you will ever meet. None of them requires anybody to have done anything wrong, and none of them changes the arithmetic on the back of the jar.
Read the unit, then the number
It is the fastest useful habit in supplement shopping, and it costs five seconds a bottle.
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