When we think of academic research, we often picture peer-reviewed journal articles and books published by well-known authors. But there's a whole world of valuable research that doesn't follow this traditional route. Enter, grey literature.
Grey literature refers to information produced outside conventional academic publishing, such as research from governments, academic institutions, businesses, and NGOs. Although it is often formally published — for example as government or NGO reports — it does not go through traditional peer-reviewed journals or commercial academic channels. Instead, it is typically distributed via institutional websites or specialised repositories.
According to the ICGL Luxembourg definition (1997, expanded in 2004), grey literature is: "Information produced on all levels of government, academia, business and industry in electronic and print formats not controlled by commercial publishing."
The term "grey " captures its in-between nature. It isn't quite formal academic publishing, but it certainly isn't informal either.
For researchers and students in the fields of food science, nutrition or health, grey literature can be a rich source of insight. It includes technical documents, industry standards, conference proceedings, and much more. These resources can offer early insights into emerging research or cover topics that traditional journals might overlook.
Grey literature can fill important gaps in the academic record. It often explores niche subjects, newly emerging topics or includes results that are null or negative, all things that commercial journals often don't choose to publish. This makes grey literature a valuable tool when conducting comprehensive research.
Additionally, grey literature brings diversity into the research landscape. It provides platforms for the voices that may not be able to professionally publish their work, meaning articles from local businesses, independent researchers or small academic institutions are able to publish work without requiring the traditional resources. This adds a broader, richer perspective to your literature search.
However, it is important to be extremely critical when using grey literature. As they are not peer reviewed articles, they might contain incorrect facts, invalid research, biases , or simply be outdated.
This means while grey literature is a vital part of a comprehensive literature search, you should never blindly trust what you read. Always cross-reference against different sources and ask yourself:
Grey literature doesn't always go by this single name, making it harder to identify in some cases. Some alternative names include unpublished literature, report literature, fugitive literature, non-conservative literature and non-traditional literature. If you are ever struggling to identify whether something is grey literature, consider two questions:
If the answer to both questions is no, then it is most likely grey literature.
In academic settings, grey literature is invaluable for providing real-world context, supporting literature reviews, informing systematic reviews, and providing up-to-date statistics and case studies. For example, a student writing about food labelling regulations might use policy documents or technical standards.
In industry, grey literature plays a crucial role in regulatory compliance, product development, and market research. A food manufacturer might rely on patents or government safety guidelines to innovate and stay compliant.
Grey literature encompasses a broad range of documents. You may have already used grey literature without realising it. Common examples in food and health research include:
Because grey literature can include a wide variety of documents, it can also be found almost everywhere. As they are not circulated by a traditional publisher, they are often distributed by a range of means. An organisation or governing body may publish their whitepaper or policy brief directly through their website. Patents must be filed with patent offices, and although they are usually available online, searching through the sheer volume of patents can be challenging.
Learn more about how to find and retrieve food science and nutrition patents
Relying on traditional search engines or AI tools to find relevant and reliable grey literature for your literature search can be challenging. The limitless amount of available data, much of which is not trustworthy or accurate, means you may struggle to find what you need. Instead, it is often better to utilise specialist databases such as FSTA (Food Science and Technology Abstracts).
If you're researching food science and nutrition, FSTA stands out as a uniquely valuable resource. Unlike general search engines or broad academic databases, FSTA is specifically designed to support research in these fields. FSTA provides a wealth of grey literature that is harder to find elsewhere and is carefully curated for the sciences of food, health and nutrition. This includes conference proceedings, patents, technical reports, and standards. These resources offer insight into current research, innovation, and regulatory developments that are highly relevant to both academic and applied contexts.
What truly sets FSTA apart from other search engines is the curation of data it holds. Everything is carefully selected by IFIS Publishing subject professionals, meaning you can use the grey literature it provides without worrying about the quality or credibility of the source. Over 2.4 million records, including academic journal articles, trade publications, patents, and more, are all discoverable in one search. Everything is tagged using keywords from the FSTA Thesaurus - the biggest food thesaurus in the world. Just one literature search can include highly relevant results from traditional journal articles and from reputable grey literature. Using FSTA, researchers and professionals can efficiently discover all of this content without having to trawl the open web.
The Future of Grey Literature
We’re currently reviewing how we identify and include grey literature in FSTA, and would welcome feedback from faculty, researchers, librarians, industry professionals, and PhD students.
Your feedback will help guide FSTA’s coverage and help us ensure it continues to meet your food information research needs. Complete the survey
Grey literature is an essential part of the research ecosystem, especially in fast-moving fields like food science and nutrition. It can provide unique insights and real-world data that you won't find in peer-reviewed journals. But it comes with responsibilities: always assess the source and consider the context.
With FSTA, you can access high-quality, expertly indexed grey literature that’s directly relevant to your field. It’s a trusted resource for students, researchers, and professionals who want to go beyond traditional publications.
Happy researching!
This article was written by guest author, Mia Askew, with additional contributions by Hannah Casbolt.