Many consumers and healthcare providers are aware that certain probiotics may be beneficial for health. But they sometimes have difficulty identifying high quality products in the marketplace.

What is a high quality probiotic product? It contains microbial strains that are properly identified, characterized and quantified, it meets specifications for purity, it is safe for its intended use, and it is manufactured in compliance with Good Manufacturing Practices appropriate for the category of the product. Further, to be called ‘probiotic’, the product must have been shown in controlled human trials to confer a health benefit.

A panel I chair under the auspices of the United States Pharmacopeia, recently collaborated on an expert opinion paper that summarizes recommendations to companies producing probiotics, outlining proper standards in quality manufacturing processes and ways to communicate quality to end users.

We recommend that probiotic producers undergo third-party evaluations to certify both probiotic quality and label accuracy. This use of a third party provides unbiased confirmation of product quality to end-users. Our paper describes the steps necessary for setting up the third-party certification of a probiotic product, in a process that is followed by established certification bodies:

  • Submission of an application to the certification body.
  • Submission of documents regarding facility statistics, a standard operating procedures index, an analytical methods index, a quality manual index, a hazard analysis, a critical control point plan and an allergen control plan.
  • Quality management systems audit.
  • Documentation review.
  • Verification of all testing methods.
  • Corrective or preventative actions.
  • Formal issuance of the certification for the product.

These steps will assure the consumer about quality in manufacturing. To improve transparency to the end-user, some organizations offering third-party certification services authorize the use of a logo or seal that makes it clear that the specific probiotic has been manufactured following stringent conditions.

It should be noted that this process is separate from assessments of the strength of evidence supporting any health claims for a probiotic product.

The panel also calls for publicly available quality standards and methods for identifying the probiotic strain, quantifying viable probiotic cells throughout production and distribution, and ensuring purity. The definition of a probiotic implies that it must be a defined entity to allow for appropriate identification to the strain level, so the panel recommends quantifying specific strains in multi-strain probiotic products. Some of the emerging methodologies that may be useful for quality assessment thus include whole genome sequencing of the bacteria to confirm the probiotic identity.

As both consumers and healthcare providers struggle to know which probiotics are backed by evidence, we recommend that the probiotic products available on the market conform to labeling standards advanced by the World Health Organization and the World Gastroenterology Organization:

  • Genus, species and strain names.
  • Statement of quantity (using colony forming units or another validated measure) of live/active microorganisms through the use-by date. (Levels of live probiotics should be provided through the ‘best by’ or ‘use by’ date and not time of manufacture).
  • Use by date.
  • Statement of benefit: although it is not required, when present, it must be supported by a human study showing the benefit at the dose delivered in the product.
  • Proper storage conditions.
  • Company contact information.

Information can be found at these links on how to read a label on a probiotic food supplement sold in the European Union and the United States.

Overall, this new expert panel document aims to provide ways of showing probiotic quality standards to consumers so they can recognize high-quality products. Currently, this goes beyond regulatory requirements in many jurisdictions. But undergoing unbiased third-party certification is a straightforward way for probiotic companies to improve transparency when it comes to probiotic product quality.



Jackson SA, Schoeni JL, Vegge C, et al. Improving end-user trust in the quality of commercial probiotic products. Front Microbiol. 2019; 10:739. doi: 10.3389/fmicb.2019.00739.