Fulvic Acid in Shilajit: Which Test Can You Trust?

If you’ve ever compared Shilajit products, you may have noticed something strange. One brand proudly claims “80% fulvic acid,” another lists 50%, while someone else insists on 30–40%. How can they all be talking about the same thing and yet be so far apart?

The short answer is this: it is not just about the Shilajit. The figures depend heavily on how the fulvic acid was measured in the laboratory. Different testing methods produce very different results, sometimes dramatically so. What looks like a superior product on paper may simply have been tested with a looser, more generous method.

This is one of the main reasons why understanding how Shilajit is properly tested is essential when comparing products. It not only clears up the confusion but also helps you see which brands are being transparent and which may be leaning on inflated numbers, and why choosing properly tested, transparently sourced Shilajit actually matters.

TOC (Total Organic Carbon)

This is one of the most common tests, largely because it is cheap and easy to run. TOC measures the total organic carbon in a sample but makes no distinction between different types of organic matter.

On the plus side, it is widely available and produces impressive-looking percentages that appeal to people browsing labels. The problem is that those numbers are highly misleading. TOC counts everything organic in the sample, not just fulvic acid. Plant residues, humic acids and all sorts of other organic compounds end up in the calculation. This lack of specificity is exactly why some methods produce inflated fulvic acid values that don’t reflect the true composition.

As a result, TOC almost always inflates the result compared with more specific methods. If you see sky-high percentages on a Shilajit label, there’s a good chance TOC was the method used.

Verdict: A rough estimate at best. Useful for a general measure of organic matter but not a reliable indicator of fulvic acid content.

The Lamar Method

The Lamar Method is more targeted. It involves oxidising organic matter with potassium dichromate and then estimating fulvic carbon using UV-Vis spectroscopy. Unlike TOC, this method was developed with humic and fulvic substances in mind, so it does a better job of narrowing in on the right compounds.

It is reproducible and reasonably affordable, which makes it appealing to many laboratories. However, it does have drawbacks. Shilajit is naturally mineral-rich, and the presence of minerals can sometimes throw off the readings, leading to underestimates. The method is also sensitive to how the sample is prepared and extracted, which means results can vary from lab to lab.

Verdict: More respectable than TOC and a step in the right direction, but it lacks international standardisation and is not considered definitive.

Titration

Titration is a classic laboratory technique where acids and bases are used to measure chemical reactions. In the context of Shilajit, titration is sometimes used on the fulvic fraction after extraction.

The appeal is obvious. It is simple, cheap, and easy for almost any lab to carry out. Even better from a marketing perspective, it often produces very high numbers that look brilliant on a product label.

Unfortunately, those numbers are often meaningless. Titration is highly non-specific and easily interfered with by other compounds. Results can swing dramatically between laboratories. Regulators do not recognise it as a valid method for fulvic acid, and within scientific circles it is considered outdated.

Verdict: Crude and unreliable. More useful for marketing claims than genuine science.

ISO 19822:2018

This is the gold standard. Introduced in 2018, ISO 19822 provides an internationally recognised method for testing humic and fulvic substances. It uses alkaline extraction to separate humic and fulvic acids, followed by gravimetric and carbon analysis. UV-Vis spectroscopy is sometimes used for characterisation but not as the main quantifier.

The strength of this method is that it is specific, reproducible, and regulator-approved. It was designed precisely for the job at hand and avoids many of the pitfalls that plague the other techniques.

The downside is that it takes longer, is more expensive to carry out, and typically produces lower numbers than TOC or titration. That may not look as glamorous on a label, but it is far more meaningful. This is also why understanding how to read a Shilajit lab report matters. A laboratory certificate is only as useful as your ability to interpret the methods behind the numbers. When you see a fulvic acid percentage based on ISO 19822, you can trust that the number reflects reality, not marketing spin.

Verdict: The most credible and trustworthy method available. If transparency and accuracy matter, this is the benchmark.

What About Eurofins and Other Big Labs?

You’ll often see Shilajit brands boast that their product has been “lab tested by Eurofins” or another big-name laboratory. On the surface, that sounds impressive. But here’s the detail most people miss: the method matters just as much as the name on the report.

Large contract labs like Eurofins typically rely on quicker, less specific methods such as UV-Vis spectroscopy (similar to the Lamar method), TOC, or even titration. These approaches are cheaper and faster, but they are not internationally standardised and often produce inflated results. These approaches also struggle to distinguish between different fractions within Shilajit’s overall composition.

This is why you’ll sometimes see very high fulvic acid numbers coming from products tested by these labs. It is not that the Shilajit is necessarily superior,  it is that the method is more generous.

In contrast, we use ISO 19822:2018. It is slower, costlier, and usually gives lower figures than the shortcut methods, but those figures are genuine, reproducible, and regulator-approved. When we say a Shilajit contains a given percentage of fulvic acid, you can be confident it reflects reality, not marketing gloss.

Other Methods You Might Hear About

Alongside the four main approaches, a few other methods crop up in discussions around Shilajit and humic substances:

• UV-Vis ratio scans (E4/E6): More about fingerprinting humic composition than quantifying fulvic acid.
  
• HPLC, NMR, FTIR: Excellent tools for research and structural characterisation but not suitable for routine fulvic percentage testing.
  
• Ash content or residue on ignition: Useful for checking total mineral content but has nothing to do with fulvic acid.
  
• HPTLC (High-Performance Thin-Layer Chromatography): Very effective for proving authenticity and detecting adulteration, but not for measuring fulvic percentages.
  

These methods are valuable for quality control and authenticity checks, but they will not give you a straightforward “% fulvic acid” number.

So, Which Method is Best?

If the goal is accuracy and transparency, ISO 19822:2018 stands above the rest. It might not give you the highest number, but it will give you the most reliable one. Understanding this makes it much easier to evaluate what actually matters when choosing a Shilajit product.

TOC and titration inflate results and risk misleading customers. The Lamar method sits somewhere in the middle, more focused but still lacking standardisation. ISO 19822 is slower and more expensive, but it delivers numbers that regulators and serious laboratories actually recognise.

For a premium brand that values honesty and purity, ISO-based testing is the strongest foundation. And for customers, it is worth remembering that bigger percentages do not automatically mean better Shilajit. Often, they simply reflect looser testing.

The bottom line: Fulvic acid is one of the most valuable components of Shilajit, but how it is measured matters just as much as how much is present. When you see big claims backed by a “lab test,” ask which method was used. If it wasn’t ISO 19822, the numbers may not tell the full story.