Scientists developed a new way to detect two types of vitamin K in cosmetics and skincare products. Vitamin K1 was once used in creams to reduce dark circles but is now banned in many countries because it can cause allergic reactions. Vitamin K2, a newer ingredient, is gaining popularity for its potential skin-soothing and anti-aging benefits. Researchers created a fast, accurate testing method that can find these vitamins in different types of products like lotions, creams, and powders. When they tested 30 real cosmetic products, they didn’t find either vitamin in any of them, but the new test could help companies and regulators make sure products are safe and contain what they claim.

The Quick Take

  • What they studied: Can scientists create a reliable test to detect vitamin K1 and K2 in cosmetics and skincare products?
  • Who participated: The study analyzed 30 different cosmetic products across six common types: water-based liquids, emulsions, creams, gels, powders, and oils.
  • Key finding: The new testing method successfully detected vitamins K1 and K2 with high accuracy and sensitivity. The test was so sensitive it could find as little as 0.02 micrograms per gram of product. When applied to 30 real cosmetic samples, neither vitamin was detected in any product.
  • What it means for you: This test helps ensure cosmetic products are safe and accurately labeled. If you use skincare products with vitamin K claims, this method helps verify those claims are true. However, this is a laboratory testing method—it doesn’t directly affect what you should do with your skincare routine.

The Research Details

Scientists created two different laboratory testing methods to detect vitamins K1 and K2 in cosmetics. The first method uses high-performance liquid chromatography (HPLC), which is like a sophisticated sorting machine that separates different chemicals so they can be identified and measured. The second method, called HPLC-tandem mass spectrometry (HPLC-MS/MS), is even more advanced and provides extra confirmation by breaking molecules into smaller pieces to identify them with certainty.

Before testing, the researchers had to prepare the cosmetic samples carefully. They mixed the products with salt water and a special solvent to extract the vitamins, then used a technique called QuEChERS (which stands for Quick, Easy, Cheap, Effective, Rugged, Safe) to clean up the samples and remove interfering substances. This preparation step is crucial because cosmetics contain many different ingredients that could confuse the test.

The researchers tested their methods on six different types of cosmetics because each type has a different texture and composition. A water-based lotion behaves very differently from an oil-based cream, so the test needed to work reliably on all of them.

This research matters because vitamin K1 is banned in cosmetics in China and the European Union due to allergy risks, but vitamin K2 is being considered as a replacement ingredient. Companies need reliable ways to test their products to ensure they don’t contain banned substances and that they accurately label what’s inside. Previous testing methods were designed for medicines and supplements, not cosmetics, so a cosmetic-specific test was needed. The QuEChERS method is faster and cheaper than older testing approaches, which means companies can test more products more affordably.

The study demonstrates strong technical quality. Both testing methods showed excellent accuracy with recovery rates between 89-108% (meaning when researchers added known amounts of vitamins, they could find 89-108% of what they added back). The methods showed very good linearity, meaning they work accurately across a wide range of vitamin concentrations. The sensitivity was excellent—the HPLC-MS/MS method could detect as little as 0.02 micrograms per gram. However, the study only tested 30 cosmetic samples, which is a moderate sample size. The study is primarily a methodology paper focused on developing and validating the testing technique rather than investigating vitamin K levels in cosmetics broadly.

What the Results Show

Both testing methods worked extremely well for detecting vitamins K1 and K2. The HPLC method could accurately measure vitamins at concentrations from 0.1 to 50 micrograms per milliliter, with a detection limit of 0.3 micrograms per gram. The HPLC-MS/MS method was even more sensitive, detecting vitamins at concentrations from 0.005 to 0.5 micrograms per milliliter, with a detection limit of just 0.02 micrograms per gram.

When researchers tested the methods by adding known amounts of vitamins to cosmetic samples, they recovered between 93-104% of the added vitamin K1 and K2 using HPLC, and 89-108% using HPLC-MS/MS. These recovery rates are considered excellent in analytical chemistry. The variation between repeated tests was very small (less than 5-10% variation), indicating the methods are reliable and reproducible.

When the researchers applied these methods to analyze 30 real cosmetic products spanning all six product types (water-based liquids, emulsions, creams, gels, powders, and oils), they found that neither vitamin K1 nor K2 was detected in any of the samples. This suggests that at the time of this study, these vitamins were not being used in the cosmetic products tested.

The QuEChERS sample preparation technique proved to be effective for cosmetic analysis. The method successfully removed interfering substances from complex cosmetic matrices, allowing clean detection of the target vitamins. The technique worked equally well across all six different cosmetic product types, demonstrating its versatility. The HPLC-MS/MS confirmation method provided additional specificity, meaning it could definitively confirm the identity of detected vitamins rather than just measuring something that looks similar.

Previous methods for detecting vitamins K1 and K2 were primarily designed for pharmaceutical products and dietary supplements, not cosmetics. Cosmetics have much more complex compositions with many interfering ingredients, making them harder to analyze. This study is one of the first to specifically address vitamin K2 detection in cosmetics. The QuEChERS approach is newer and more efficient than traditional sample preparation methods like liquid-liquid extraction or solid-phase extraction, which are time-consuming and use more solvents. The dual-method approach (HPLC with HPLC-MS/MS confirmation) follows current best practices for analytical chemistry.

The study tested only 30 cosmetic samples, which is a relatively small number for drawing broad conclusions about vitamin K use in cosmetics. The samples were limited to six common product types, so the method may need additional validation for unusual cosmetic formulations. The study was conducted at one point in time, so it doesn’t show whether vitamin K use in cosmetics has changed over time. The research doesn’t explain why no vitamins were detected—it’s unclear whether companies simply aren’t using these ingredients or whether the samples tested happened to not contain them. The study is primarily a methodology paper, so it focuses on whether the test works rather than investigating real-world vitamin K use in cosmetics.

The Bottom Line

This research provides a validated testing method for cosmetic manufacturers and regulators to use. If you’re a cosmetic company, you can use this method to verify your products don’t contain banned vitamin K1 and to confirm the presence of vitamin K2 if you claim to use it. If you’re a consumer, this research supports the importance of regulatory testing to ensure cosmetic safety and accurate labeling. The confidence level for the testing method itself is high—the technique is reliable and accurate. However, the confidence level for claims about vitamin K use in cosmetics is lower because only 30 products were tested.

Cosmetic manufacturers should care about this research because it provides a reliable way to test their products for regulatory compliance. Regulatory agencies should care because they can use this method to verify that banned vitamin K1 isn’t being used in cosmetics. Consumers interested in vitamin K skincare products should care because this research supports the development of better quality control. People with sensitive skin or vitamin K allergies should care because better testing helps ensure products are safe. This research is less relevant for people who don’t use cosmetics or who aren’t concerned about ingredient verification.

This is a laboratory testing method, not a treatment or supplement, so there’s no timeline for seeing personal benefits. However, if cosmetic companies adopt this testing method, consumers may see improved product safety and more accurate labeling within months to a few years as the method becomes standard practice.

Want to Apply This Research?

  • Track cosmetic products you use that claim to contain vitamin K, noting the brand, product type, and claimed benefits. Record any skin changes you notice (improvements in dark circles, skin texture, irritation) over 4-8 weeks to see if products match their claims.
  • If you’re interested in trying vitamin K skincare products, use this research as motivation to choose products from companies that conduct rigorous testing. Look for brands that mention third-party testing or quality verification. Keep a simple log of which vitamin K products you try and how your skin responds.
  • Create a long-term tracking system for skincare products and skin condition. Note the product name, type, claimed ingredients, and your skin’s response (using photos and written observations). Over 3-6 months, you can determine which products actually deliver on their vitamin K promises. This personal tracking complements the laboratory testing described in this research.

This research describes a laboratory testing method for detecting vitamins in cosmetics—it is not medical advice. The findings do not establish that vitamin K products are safe or effective for treating skin conditions. Vitamin K1 is banned in cosmetics in China and the European Union due to allergy risks. Before using any new skincare product, especially if you have sensitive skin or known allergies, consult with a dermatologist. This study does not evaluate the safety or efficacy of vitamin K2 in cosmetics for human use. Always follow product instructions and discontinue use if you experience irritation or allergic reactions.