The ocean’s diverse seaweeds are full of nutrients and can be very tasty. While seaweed is common in many Asian dishes, it is not as popular in many traditionally European cuisines. However, this was not always the case. New archaeological evidence also shows that early Europeans ate seaweeds and freshwater plants 8,000 years ago. The findings are described in a study published October 17 in the journal Nature Communications and anchor the plants in the past.

[Related: Why seaweed is a natural fit for replacing certain plastics.]

In the study, researchers examined biomarkers that were taken from the calcified dental plaque of 74 individuals found at 28 archaeological sites from northern Scotland to southern Spain. The plaques revealed “direct evidence for widespread consumption of seaweed and submerged aquatic and freshwater plants.”

The samples where biomolecular evidence survived showed signs that red, green, or brown seaweed and freshwater aquatic plants were eaten. One sample from Scotland’s Orkney archipelago also had evidence of a type of sea kale. The researchers also found that seaweeds and freshwater plants were continually eaten in Europe into the Early Middle Ages. 

“Not only does this new evidence show that seaweed was being consumed in Europe during the Mesolithic Period around 8,000 years ago when marine resources were known to have been exploited, but that it continued into the Neolithic when it is usually assumed that the introduction of farming led to the abandonment of marine dietary resources,” study co-author and University of York bioarchaeologist Stephen Buckley said in a statement.

The nutritional benefits from eating seaweed were likely very well understood by ancient European populations. Some historical accounts report laws related to collection of seaweed in Iceland, France, and Ireland dating back to the 10th Century. Sea kale is also mentioned by Roman naturalist and writer Pliny as an anti-scurvy remedy for sailors on long sea voyages. Through the 18th century, seaweed was considered a famine food and is featured in a popular Irish-language folk song

[Related: Why seaweed farming could be the next big thing in sustainability.]

Currently, there are roughly 10,000 different species of seaweeds around the world, but only 145 species are regularly consumed. Depending on the type of seaweed, the plants are a great source of fiber, iron, and potassium among other vitamins and minerals. Cultivating seaweed can also be very environmentally friendly, as the seaweed produces oxygen while absorbing excess nitrogen in the water.

“Our study also highlights the potential for rediscovery of alternative, local, sustainable food resources that may contribute to addressing the negative health and environmental effects of over-dependence on a small number of mass-produced agricultural products that is a dominant feature of much of today’s western diet, and indeed the global long-distance food supply more generally,”  study co-author and University of Glasgow archaeologist Karen Hardy said in a statement. “It is very exciting to be able to show definitively that seaweeds and other local freshwater plants were eaten across a long period in our European past.”