A nutrient-rich food that has largely disappeared from Western diets was a staple of early Europeans, research shows.

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An analysis of molecules preserved in fossilized dental plaque has shown them to be virtually absent from most Western diets today.

Evidence of hitherto hidden flavors for these nutrient-rich plants and algae has been difficult to detect in the archaeological record, according to research published Tuesday in the journal Nature Communications. When researchers previously discovered evidence of seaweed, they explained its presence as a type of fuel, food wrap or fertilizer.

Previous research has suggested that the adoption of agriculture, starting about 8,000 years ago, caused ancient humans to stop eating seaweed. In Europe, by the 18th century, seaweed was considered a famine food or only suitable for animal feed.

Study author Karen Hardy, professor of prehistoric archeology at the University of Glasgow, said: “It is exciting to be able to demonstrate unequivocally that seaweeds and other local freshwater plants have eaten for a long time in our European past.”

A dietary link to the sea

Hardy and a team of archaeologists from the University of Glasgow and the University of York in the United Kingdom examined the teeth of the first 74 people unearthed at 28 archaeological sites across Europe, including the far north. Scotland, southern Spain and Lithuania.

The oldest sites considered in the study in Spain and Lithuania date back more than 8,000 years ago, while the most recent site is about 2,000 years old.

The researchers were able to detect identifiable chemical signatures in tartar, bacterial residue, and food debris that accumulates on teeth over time in 37 samples from 33 individuals. And of those, 26 samples revealed that seaweed or aquatic plants were on the menu.

Dental plaque is very common and once developed it can only be removed by scraping. Today, this is what dentists do as part of the cleaning process, Hardy explained via email.

But before, it just accumulated, especially in the small gaps between teeth and gums. It is common across most archaeological material throughout the past, Hardy adds. It acts as a trap for material entering and passing through the mouth. Since it is found in the mouth, all material found therein is clearly associated with ingestion.

According to the study, seaweeds, freshwater algae and aquatic plants have distinct, unusual and complex organic chemical compositions, allowing the conservation and detection of highly resilient biomarkers from The three types of organic compounds are lipids, amino acids and alkylpyrroles.

“It was this particular combination of biomarkers that allowed us to identify seaweed and food,” study co-author Stephen Buckley, a researcher in the department of archeology at the University of York, said by email. aquatic creatures”.

Other plants have their own distinctive biomarkers, but they tend to survive less well in archaeological contexts than algae (e.g. seaweed, a type of macroalgae), so they we can say that seaweed and aquatic plants were ingested and therefore consumed, but we do not necessarily get a full picture of ALL the foods consumed, which could may depend on prevailing environmental conditions.

An analysis of the samples shows that ancient humans ate, or at least chewed, red, green and brown seaweed and a variety of freshwater aquatic plants, such as pondweeds and vegetation same genus as water lily.

This clearly shows that the nutritional benefits of seaweed were so well understood by ancient peoples that they maintained a dietary connection to the sea, says Buckley.

Among the remains studied, those found in graves or chambered graves in Orkney, an archipelago of islands off the coast of Scotland, also revealed biological molecular evidence of the consumption of seaweed, including cabbage, most likely sea kale.

And the study notes that it’s not just coastal communities that eat seaweed. At La Corona, a site in southeastern Spain occupied from 6059 BC to 5849 BC, seaweed was part of the diet even though it was 80 km from the coast (49, 7 miles).

Buckley added that it is impossible to be certain whether the seaweed is cooked or eaten raw.

However, he said it was reasonable to assume that seaweed would be a staple food because of its nutritional benefits and the ease of obtaining it from the coast.

Dubbed a superfood, there are about 145 species of seaweed eaten today, mainly in Asia, and they are known to have many health benefits.

Scientists say they hope that their research will highlight the potential for including more seaweed and freshwater plants in today’s diets.

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