So I'm quite into foraging, and seaweed (the real thing not chinese take away stuff...) is supposedly very nutritious for you and very easy to forage up, but are there any seaweeds which are not edible, or possibly not worth eating, on UK shorelines?


There is one poisonous: the Desmarestia. The other species should be okay. However, I can't say anything about if they are "worth eating" :)

Desmarestia is a genus of brown algae found worldwide. Members of this genus can be either annual or perennial. Annual members of this genus can produce and store sulfuric acid in intracellular vacuoles. When exposed to air they release the acid, thereby destroying themselves and nearby seaweeds in the process. They are found in shallow intertidal areas.

Avoid this


So I went and asked Professor Michael Guiry, Director of AlgaeBase and world authority on seaweed. Here’s his reply:

“As far as I know, there are no really poisonous seaweed in this part of the world. “Our” Desmarestia species (4 of them and as you said mostly in deep water) produce sulphuric acid and can have a cellular pH of 2.

Anything else you might want to eat is free of poisons in the conventional sense as far as I am aware. However, care should be exercised when collecting in areas with high coliform counts and other bacteria, particularly in estuaries.


Further reading: blog post by Ginger Hultin

  • I'll delete this paragraph... Is really subjective over all.
    – OddDeer
    Dec 2 '15 at 8:38
  • 2
    Regarding the deleted paragraph - I wonder what they've got against that part of the coast... I live in Felixstowe, and (up until a couple of years ago, not had it renewed for what seems like administrative/political reasons) we regularly had a Blue Flag award despite being host to the UK's biggest container port... Dec 2 '15 at 11:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.