“50% Fulvic Acid”: 50% of What? How to Compare Shilajit Lab Results Properly

Lab reports are reassuring things. They come with numbers, decimal places, recognised analytical methods and official-looking certificates. When one Shilajit product claims 60% fulvic acid and another claims 45%, it's understandable that a consumer might assume the first contains substantially more of whatever the lab has measured.

It might. But there's also a possibility that the two numbers aren't directly comparable, or that the apparently higher percentage describes something rather different from what the person buying the product thinks it does.

A percentage is always a proportion of something. In analytical chemistry, that means understanding both what was measured and the amount of material against which it was calculated. In Shilajit testing, one particularly important distinction is whether results are reported on a dry basis or an as-is basis. The same resin can produce quite different percentages depending on which is used, even though its underlying composition hasn't changed.

At One Life Foods, we believe reporting Shilajit's fulvic fraction on an as-is basis is the more honest approach for consumers. It's how we choose to express our results because it relates to the product being purchased, including the water naturally present in the resin. When somebody buys a jar of Shilajit, they aren't buying the dried analytical material that may have been prepared in a lab. They're buying the finished resin.

Dry-basis reporting isn't scientifically wrong. It's useful for comparing the composition of dry material, particularly when moisture levels differ. But there's an important difference between using that figure in a technical report and turning it into a headline claim without explaining what the percentage represents.

A dry-basis result can be entirely valid while giving consumers an inflated impression of the proportion present in the product they actually receive. We think the reporting basis should be clear enough that nobody needs a background in analytical chemistry to work out what they're paying for.

Why can two Shilajit fulvic acid results be different?

Laboratories can produce different results because they measure different chemical fractions, use different extraction methods, prepare samples differently or express their findings on different reporting bases. Even when the method is nominally the same, representative sampling and ordinary analytical variation can contribute to differences.

Before comparing two percentages, it's necessary to establish whether the labs measured equivalent material under comparable conditions. A figure labelled 'fulvic acid' doesn't automatically answer that question because fulvic substances are complex mixtures rather than one chemically defined molecule.

There's also the denominator.

A result expressed on a dry basis describes the measured fraction relative to the dry material in the sample. An as-is result expresses it relative to the sample in its original condition, including moisture.

Consequently, 50% on a dry basis isn't the same thing as 50% as-is. The percentages might look identical, but they're referring to different quantities of material.

This is where a legitimate analytical convention can become a consumer transparency problem. A brand can quote a higher dry-basis figure, omit the basis from the prominent marketing claim, and leave the reader with the impression that the finished resin contains that percentage by weight.

The lab may have done nothing wrong. The problem lies in how its result has been communicated.

What does 50% fulvic acid actually mean?

Consider a hypothetical Shilajit resin containing 20% water.

That means 100 grams of finished resin contains 80 grams of dry material. Now suppose an analytical method identifies a particular fulvic fraction representing 50% of those dry solids.

The dry-basis result is 50%, but the measured fraction represents only 40 grams of the original 100 grams of resin.

The calculation is straightforward:

As-is percentage = dry-basis percentage × dry-matter fraction

In this example:

50% × 0.80 = 40% as-is

Reporting basis	Fulvic fraction
Dry basis	50%
As-is basis	40%

Both figures describe the same representative sample. Neither involves a change in the actual composition of the resin. The difference is entirely a consequence of whether the water was included in the denominator.

From a laboratory perspective, there are reasons to report either figure. From a consumer perspective, however, we'd argue that the 40% figure is the more meaningful headline result because it describes the proportion of the measured fraction in the resin as supplied.

If the product is sold as a resin, the water is part of what the customer purchases. Removing that water mathematically before quoting the percentage may produce a useful technical comparison, but it doesn't describe the composition of the finished product by weight.

That's why One Life Foods favours as-is reporting. It's not because the number is necessarily more impressive. In fact, it's usually lower whenever the sample contains moisture. We consider it a better representation of what the customer actually receives.

What does dry basis mean?

A dry-basis result excludes moisture from the denominator. It answers the question: Of the dry material in this sample, what proportion was measured as the specified constituent or fraction?

This can be useful when comparing raw materials with different moisture contents. If the aim is to understand differences in the composition of their dry solids, removing water from the calculation can make those comparisons more informative.

But the result doesn't directly tell a consumer what percentage of the resin in the jar consists of that measured material.

What does as-is mean?

An as-is result uses the whole representative sample as the denominator, water included. A lab may also use the term as-received, although it's worth confirming how a particular lab defines its reporting terminology.

Where the sample tested accurately represents the product being sold, an as-is result describes the measured proportion in that finished material.

For a consumer-facing Shilajit percentage, we think that's the clearer basis.

The distinction isn't that dry-basis analysis is dishonest. It's that an unqualified dry-basis percentage can easily be misunderstood when presented as though it describes the finished resin.

How much can moisture change the headline percentage?

The effect becomes more obvious when several moisture levels are compared.

Suppose the dry material consistently contains 50% of the same analytically defined fulvic fraction, measured using the same method. Only the amount of water in the finished resin changes.

Water in resin	Dry material	Fulvic fraction, dry basis	Equivalent as-is result
5%	95%	50%	47.5%
10%	90%	50%	45.0%
20%	80%	50%	40.0%
30%	70%	50%	35.0%

These are hypothetical calculations, not measurements of particular commercial products. They illustrate how a percentage can change simply because the amount of water included in the denominator changes.

The same issue affects how much actual dry material someone receives per serving. Our guide to Shilajit concentration, water content and total solids explains why two jars with the same labelled weight may contain different amounts of non-water material.

The dry material in every example has the same measured composition. Yet a customer buying the finished resin would receive a different amount of that fraction per gram of product.

For somebody trying to understand what's actually in their jar, that isn't a trivial detail.

An as-is result also makes it easier to interpret the measured fraction relative to an amount consumed. If a resin is reported as containing 40% of a defined fraction as-is, that corresponds mathematically to 400 milligrams of the reported fraction per gram of representative product, subject to the validity of the measurement and its uncertainty.

That doesn't establish bioavailability or clinical effectiveness. It simply expresses the analytical result relative to the material being sold, rather than a dried version of it.

The apparent winner can change

Imagine two Shilajit products tested using the same analytical method.

Product A contains 20% water and reports 50% of the measured fulvic fraction on a dry basis. Product B contains 5% water and reports 43% of the same fraction on an as-is basis.

At first glance, Product A looks stronger: 50% versus 43%.

But after converting both results to an as-is basis, the comparison changes.

	Product A	Product B
Water content	20%	5%
Fulvic fraction, dry basis	50%	Approximately 45.3%
Fulvic fraction, as-is	40%	43%

Product A has the higher proportion of the measured fraction within its dry material. Product B has the higher proportion within the finished resin as sold.

If the objective is to compare dry solids, Product A comes out higher. But if the question is which product provides more of the measured fraction per gram of resin purchased, Product B comes out higher.

We believe the second comparison is the more honest one to present to consumers buying a finished Shilajit resin.

A consumer looking at an unqualified claim of '50% fulvic acid' is unlikely to assume that the figure applies only after moisture has been mathematically excluded. They're much more likely to understand it as 50% of the product they're buying.

The distinction can be explained without suggesting that the dry-basis lab result was false. It's the presentation of that result, particularly when the reporting basis has been omitted, that deserves scrutiny.

Of course, neither result establishes which product is more biologically effective, and even this comparison assumes both laboratories measured an equivalent fulvic fraction using appropriately comparable methods. That brings us to the other major complication.

Why the analytical method matters just as much as the percentage

Shilajit isn't one chemically defined substance. It's a complex natural material containing a mixture of organic compounds, inorganic constituents and water, with composition influenced by its origin, processing and other factors.

The term fulvic acid is commonly used as though it describes one specific molecule that can be measured in the same way as a purified chemical compound. In reality, fulvic substances are heterogeneous mixtures, and lab methods often define the material being measured through the extraction and separation procedures used.

An analytical result therefore needs to be interpreted in the context of the method that produced it.

What does ISO 19822 actually measure?

ISO 19822:2018 provides a standardised procedure for determining humic acids and hydrophobic fulvic acids in certain materials, including geological deposits and ingredients used in fertilisers and soil amendments. It wasn't developed specifically as a food-supplement standard for finished Shilajit products.

We use ISO 19822 as an analytical reference point because it provides a defined approach to the extraction and measurement of humic and hydrophobic fulvic fractions. The method separates particular fractions of organic material through specified chemical procedures rather than treating every substance soluble during extraction as equivalent fulvic acid.

In particular, the hydrophobic fulvic acid fraction is operationally defined by properties including its behaviour during extraction and adsorption onto a suitable resin.

That makes the method useful for characterising a specified fraction of complex material, but it doesn't mean the result represents every substance that might be called fulvic acid under another method. Nor does it establish that the reported fraction consists of one chemically pure molecule.

The method also involves drying and weighing procedures for solid analytical samples. Consequently, it's important to understand how the final result has been calculated and whether the reported percentage relates to dried analytical material or the original sample.

ISO 19822 was amended in 2026 to provide an alternative to the DAX-8 resin previously used for separating the hydrophobic fulvic fraction. The relevant method version and laboratory procedures should therefore be identifiable when detailed comparisons are being made.

The important consumer question remains the same: What fraction was measured, and what proportion of the finished product does the reported percentage actually represent?

What does ash-free mean?

Another term that may appear in humic and fulvic analysis is ash-free.

Ash refers to the inorganic residue remaining after controlled combustion under specified conditions. When an isolated analytical fraction is corrected for ash, the intention is to avoid including inorganic residue in the reported organic fraction.

This correction serves a different purpose from excluding moisture from the original sample.

Dry-basis reporting concerns the sample's water content. Ash correction concerns inorganic residue associated with the isolated fraction.

An ash-free result doesn't automatically mean the original Shilajit contains no minerals, and it certainly doesn't mean the isolated organic material is one chemically pure substance.

It's quite possible for an analytical result to involve both ash correction and a dry-basis calculation. The lab report should make these steps understandable rather than leaving a consumer to interpret an impressive percentage without context.

Can results from different fulvic acid methods be compared?

Not necessarily.

Two laboratories could report their findings on exactly the same as-is basis and still produce results that aren't directly comparable if they measure different chemical fractions.

One method may separate a specific hydrophobic fraction. Another might use an approach involving absorbance, carbon measurement, titration or a different extraction procedure.

These methods don't necessarily have the same specificity or measure equivalent material.

This creates two separate questions for every percentage:

What exactly was measured?

What amount of material was it measured against?

An as-is result answers the second question more transparently for consumers, but it doesn't resolve differences in analytical methodology.

We wouldn't regard an as-is figure as automatically trustworthy if the method behind it was unsuitable or poorly defined. Honest reporting requires a meaningful method, representative sampling, appropriate analytical quality and a clearly stated basis.

The differences between separation-based methods, titration, spectroscopy and total organic carbon are examined in our guide to fulvic acid testing methods and which results can be trusted

Can two laboratories using the same method still disagree?

Yes. Analytical measurements have uncertainty, and complex natural materials introduce additional challenges.

Two labs examining representative portions of the same Shilajit may produce slightly different results because of sample preparation, extraction efficiency, handling, moisture variation or ordinary differences in laboratory performance.

Even two measurements performed within the same laboratory may not be numerically identical.

For example, a result of 49.8% from one lab and 50.6% from another doesn't automatically demonstrate that the underlying samples have meaningfully different compositions. Whether the difference is significant depends on the method's precision, the reported measurement uncertainty and the quality of the samples.

The number of decimal places on a certificate shouldn't be confused with the certainty of the measurement.

Representative sampling is particularly important. A test result describes the material submitted and analysed, not necessarily every gram produced by a supplier. If a resin isn't sufficiently homogeneous, or the tested portion doesn't represent the batch being sold, a technically competent analysis may still provide a misleading impression of the finished product.

The same applies to moisture measurements. A dry-basis result can be converted to an as-is result when the dry-matter content of the same representative material is known. Using an unrelated moisture figure from a different batch, or assuming that every resin from a particular supplier contains the same amount of water, can undermine the calculation.

Analytical comparison requires more than placing two certificates next to one another and deciding which has the biggest number.

Water content and loss on drying aren't always identical

Water-specific testing methods are intended to measure water. Loss on drying, commonly abbreviated to LOD in this context, measures the mass lost when a material is dried under specified conditions.

Water may account for most of the loss, but other volatile substances can contribute depending on the material and drying conditions.

Consequently, a loss-on-drying result isn't necessarily an exact water measurement.

When converting dry-basis percentages to as-is values, it's important to understand how the lab obtained its dry-matter figure. A mathematically correct calculation can still be misleading if the underlying measurement doesn't represent what the analyst assumes it does.

This is also why the moisture or dry-matter determination should relate to the same representative material used for the compositional analysis.

What do common Shilajit lab tests actually tell us?

A Shilajit certificate of analysis may contain results from several different analytical techniques. Each addresses a particular question, and none provides a complete description of the material on its own.

Analytical test	What it can help establish	What it can't establish by itself
ISO 19822	Defined humic and hydrophobic fulvic fractions	Complete Shilajit composition, authenticity or clinical potency
ICP-MS / ICP-OES	Concentrations of specified elements	Every element's chemical form or biological availability
Ion chromatography	Concentrations of selected inorganic ions	Complete organic or mineral composition
HPLC	Separation and, where appropriately validated, quantification of selected compounds	Every compound present in the material
LC-MS	Molecular features and potentially identifiable or quantifiable compounds	That every detected compound produces a biological effect
GC-MS	Compounds suitable for the extraction and chromatographic conditions used	The entire complex organic matrix
FTIR	Spectral features associated with chemical bonds and functional groups	A complete quantitative ingredient list
Water analysis	Water content under the specified method	Authenticity or biological activity
Loss on drying	Mass lost under defined drying conditions	That all lost mass was water
Microbiological testing	Specified microbial contamination	Chemical authenticity or absence of every possible contaminant
Heavy-metal testing	Concentrations of specified elements	That every contaminant has been excluded or that chemical species are known

An elemental result, for example, may identify how much arsenic is present without establishing the proportions of its different chemical forms. Those forms can have different toxicological significance, so total elemental concentration isn't always the complete analytical picture. For more on the differences between elemental detection, chemical form and actual exposure, see our explanation of heavy metals in Shilajit and how to interpret the results

Similarly, identifying a particular organic compound doesn't establish that it's present in a biologically meaningful quantity, survives digestion, reaches a target tissue or produces a clinically relevant effect.

Analytical detection is evidence of what a method found under its conditions. It's not a shortcut to proving health benefits.

One lab test can be highly informative for one purpose and largely irrelevant for another. A certificate showing a high fulvic fraction doesn't establish microbiological safety, just as a passing heavy-metal result doesn't demonstrate that the product contains a particular amount of fulvic material.

Why lab results don't necessarily add up to 100%

A Shilajit certificate may show a percentage for a fulvic fraction, another percentage for humic material, moisture, elemental concentrations in milligrams per kilogram and perhaps a list of compounds detected by chromatography.

It's tempting to regard all these findings as separate slices of the same product and subtract them from 100% to determine what's left.

That usually isn't justified.

The tests may use different sample preparations, reporting bases and methods. Some results measure analytically defined fractions, while others identify individual elements or compounds that may already be included within broader measurements.

A compound identified by chromatography could form part of an organic fraction measured through another technique. Adding both figures together would risk counting the same underlying material twice.

The percentages may also have been corrected or calculated differently.

Unless the measurements were specifically designed to form a complete and internally consistent mass-balance assessment, there's no reason to expect them to add up perfectly to 100%.

The apparent precision of a report doesn't make every number directly additive.

Units, detection limits and the problem with small numbers

Percentages aren't the only figures that can be misunderstood.

Laboratories may report results in percentages, milligrams per kilogram, micrograms per gram or parts per million. For mass-based concentration measurements:

1 mg/kg = 1 µg/g = 1 ppm by mass

And:

1% = 10,000 mg/kg

That means a result of 0.1% is equivalent to 1,000 mg/kg. It's therefore larger than 500 mg/kg, even though the number 500 might initially attract more attention.

Always compare equivalent units and reporting bases before drawing conclusions.

What do ND, LOD and LOQ mean?

Lab reports also use terminology associated with detection and quantification.

LOD, in this context, means the limit of detection. It concerns the lowest concentration or quantity at which an analytical method can reliably distinguish the presence of a substance under defined conditions.

LOQ means the limit of quantification, associated with the level at which a substance can be measured with acceptable analytical performance.

ND generally means not detected under the method's specified criteria.

None of these terms automatically means that the concentration is absolutely zero.

Similarly, a result reported as less than 0.1 mg/kg means it falls below the stated threshold. Whether that threshold represents a detection limit, quantification limit or reporting limit depends on the lab.

These details become especially important when interpreting contaminant results, where an apparently reassuring 'not detected' statement is only as informative as the sensitivity and suitability of the method behind it.

A product tested with a poorly suited or insufficiently sensitive method shouldn't be considered safer merely because the certificate displays more instances of 'ND'.

What does '99% pure Shilajit' actually mean?

On its own, very little.

A product advertised as 99% pure might be referring to dry matter, extracted material, the absence of added ingredients or some other measure. Without a clearly stated definition and an appropriate analytical method, the number doesn't establish much.

Shilajit is a complex natural material, not a single chemically defined molecule that can be assigned a simple purity value in the same way as a highly purified reference compound. We've explored the different organic fractions, mineral constituents and smaller compounds in our chemical map of Shilajit

A claim of 99% purity therefore raises an obvious question: 99% of what?

The same question applies to prominent fulvic acid percentages.

A large number may be accurate within a specific analytical definition, but it's only informative when the method and reporting basis are clear.

One Life Foods' preference for as-is reporting comes from the same principle. We think consumers should be able to relate a reported proportion to the finished product they're buying, rather than having to work backwards from a more flattering analytical basis.

That doesn't mean every dry-basis claim is deceptive. A clearly identified dry-basis result may be entirely appropriate in a technical comparison. But if a product advertises an impressive percentage without making the basis visible, consumers have good reason to ask whether it represents the resin as sold.

Can one lab test prove that Shilajit is authentic?

No single routine test can establish every relevant aspect of Shilajit identity, composition and safety.

A more complete assessment may involve humic fraction analysis, an elemental profile, selected organic markers, moisture measurement, contaminant testing, microbiology and information about raw-material origin and processing.

These different sources of evidence are complementary. A strong result in one doesn't compensate for a serious problem in another.

It's also important that a certificate relates to the material actually being sold.

Consumers reviewing a lab report should look for details such as the tested product name, sample identification, batch number, analysis date, analytical method, results and laboratory information. If the product being purchased belongs to a different batch, the report may not establish its composition.

For a practical explanation of certificates, laboratory accreditation, batch traceability and analytical methods, see our guide to reading a Shilajit laboratory report

Laboratory accreditation can provide useful assurance about competence, but the scope of that accreditation should also be relevant to the particular method or test being claimed.

The presence of a laboratory logo, an ISO reference or a long collection of analytical results doesn't automatically prove that every claim made about the product has been verified.

A useful certificate should make the evidence easier to understand, not require the customer to take everything on trust.

Six questions worth asking before comparing Shilajit lab reports

Before deciding that one product has a higher or more impressive fulvic acid result, it's worth checking the following:

1. What exactly was measured? Was it a defined hydrophobic fulvic fraction, a broader extract or something else?

2. Which analytical method was used? Are the methods equivalent and suitable for the material?

3. How was the sample prepared? Was moisture removed, and were the fractions isolated or corrected in a particular way?

4. What's the reporting basis? Is the percentage as-is, dry basis or another explicitly defined basis?

5. Are the units and samples comparable? Do the figures relate to representative material, and is the report relevant to the product batch?

6. How certain is the result? Does the apparent difference justify a meaningful conclusion when method performance and measurement uncertainty are considered?

These questions aren't intended to make lab testing seem unnecessarily complicated. They help distinguish meaningful comparisons from numbers that only appear comparable.

Why we believe as-is reporting is the more honest approach

There's a legitimate place for dry-basis reporting in analytical chemistry. Comparing the dry composition of materials with different moisture levels can be useful, and properly labelled dry-basis results shouldn't be dismissed simply because the figures are higher.

But Shilajit sold as a resin is purchased and consumed as a finished material. The water in that resin contributes to its weight, and therefore to the amount of a measured fraction present per gram of product.

For that reason, we believe the as-is percentage is the more transparent consumer-facing figure. It's also the basis on which One Life Foods chooses to present its Shilajit results.

We're not arguing that an as-is percentage automatically demonstrates superior quality, potency or biological effectiveness. The analytical method still matters, as do representative sampling, safety testing and the many aspects of Shilajit composition that one percentage can't describe.

Our position is simpler. When a consumer sees a claim that a resin contains a particular percentage of a measured constituent, they should reasonably be able to understand that percentage as referring to the product in the jar.

If the result was instead calculated after removing moisture, the brand should make that clear rather than allow the higher number to speak for itself.

A lab report can be technically correct while the way it's used in marketing creates a misleading impression. Shilajit's chemistry is complicated enough without making the denominator unnecessarily mysterious.

The percentage matters. What it was measured against matters just as much.

And when we're talking about the product somebody actually buys, we'd rather use the number that describes what's in the jar.

Technical references and further reading

ISO 19822:2018. Fertilizers and soil conditioners: Determination of humic and hydrophobic fulvic acids concentrations in fertilizer materials.

https://www.iso.org/standard/66271.html

ISO 19822:2018/Amd 1:2026. Amendment 1: DAX-8 resin alternative.

https://www.iso.org/standard/87295.html

Eurachem/CITAC. Quantifying Uncertainty in Analytical Measurement, Third Edition (2012).

https://eurachem.org/index.php/publications/guides/quam

Eurachem. Terminology in Analytical Measurement: Introduction to VIM 3, Second Edition (2023).

https://eurachem.org/index.php/publications/guides

The numerical examples in this article are hypothetical and demonstrate reporting-basis calculations. They aren't measurements of particular brands or commercial Shilajit products. Valid product comparisons require suitable, comparable analytical methods and representative samples.

Written by

Chris Simon, Founder of One Life Foods.

Chris has worked in the supplement industry since 2009 and is known for seeking out exceptional ingredients, products, and formulations. Read more about Chris and the story behind One Life Foods.