Dulse has particularly fine gastronomic qualities, and it can be commercially grown in tanks.Previously other scientists from i.a. the Danish Veterinary and Food Administration have cautioned that dulse may contain dangerous levels of the neurotoxin kainic acid, which, when consumed in large doses, can lead to brain damage. Professor Mouritsen's research now shows that dulse contains only extremely small doses of kainic acid, and that a person needs to eat 150 kg fresh dulse in one go in order to experience the poisoning effect observed in animal studies.
"Dulse is - when you observe common sense rules for freshness and hygiene when handling food - perfectly safe to eat. No person can eat 150 kg in one go", says professor Mouritsen.
He and his colleagues also measured dulse's content of heavy metals, inorganic arsenic and iodine - substances that may occur in seaweeds and may be harmful in large doses.
Dulse contains only very small concentrations of iodine, arsenic, mercury, cadmium and lead, and they are all below the WHO-defined limits. Nor the content of vitamin K is alarmingly high.
"Not even people who take blood thinning medicine need to worry if they eat dulse in moderation," says professor Mouritsen.
Two well-known seaweed species (Sargassum muticum
and Sargassum fusiforme
) are known to have a very high content of inorganic arsenic, which increases the risk of cancer. S. fusiforme
is not found in North Atlantic waters, but can be purchased in stores. S. muticum
is found in North Atlantic waters.
For his own part professor Mouritsen is not nervous to harvest and eat seaweed from North Atlantic waters.
"There are many delicious, healthy and safe seaweed species in North Atlantic waters. Just stay away from old seaweed washed up on the beach and harvest only seaweed from clean waters", he adds.
Dulse is a particularly delicate seaweed, he points out, and he is supported by restaurant chefs. Through time dulse has been one of the most popular seaweed species in the parts of the western world with a tradition for eating seaweed.
"Dulse has a very appealing taste. It tastes best as dried and can be added to bread, omelets, soups and fish dishes. It can be fried and served as a crisp substitute for bacon or sprinkled over a salad", suggests professor Mouritsen.