Seaweed, how much is too much ?

[Toddy]

I confess that I have always loved salty green stuff. Samphire is a delight, brassicas are dinner, nettles are good food, so is a plethora of the weeds.

I am a little fat lady but my diet's rich in good stuff.

I have become addicted to the Itsu seaweed thins. Happily have a pack a day ....look a biscuit is an occasional treat, I had one a week ago, but I don't really have a sweet tooth. I'm a good vegetarian, and savoury green stuff is much more appealing.

The issue is that the packs come with warning about not eating too much since it can affect your thyroid......now I mind as a child happily eating the kelp, chewing on the stalks, and for years I have said to folks that there are no poisonous seaweeds round out coasts (well, in sewage free areas) and reading the wee sachet of lovely tasty green munchiness this afternoon it occurred to me that I don't know how much seaweed we can actually safely eat.

Anyone know ?

 

[Broch]

Mainly, it's the iodine content that is bad for the thyroid. Brown seaweeds are considered to be higher. I'll see if I have some guidelines for quantities and which ones are considered lowest.

 

[Broch]

OK, based on my rough notes:

Laverbread, such as Porphyra umbilicalis, has about 13-80 micro grams of iodine per gram of dried seaweed. Some kelp species have thousands of micro grams per gram. But, that isn’t the whole picture because effects can be cumulative. So, even our fried laverbread and oat breakfast may not be healthy if we ate it every day.

My understanding, and based on the notes I have typed up, is that it’s only a problem for people with existing thyroid problems or for people already taking iodine supplements. Then, of course, we know that seaweeds are very good at absorbing other elements – heavy metals and arsenic.

According to Geoff Dann there isn’t enough research to be conclusive about the safety of eating seaweed but at the same time there do not seem to be many actual reported problems even in communities (like South Wales) that have a tradition of eating it regularly.

 

[Toddy]

Cheers @Broch

I wonder if we can find Korean or Japanese research on it ?

I'm a little concerned because for years I've been telling folks it's all edible, and while it is, just how much has never been a factor.

I have to be really careful with the seaweeds, much though I love them, because I'm allergic to fish, but it's not a horrendous allergy...just hives, hay fever, throw up.... and some of the seaweeds aren't as clean of mini shellfish bits as they might be. The Itsu stuff, and the Korean ones I bought online, have been excellent, no need for the rapid ingestion of anti histamines

 

[demented dale]

Theres a lady here on the West Coast of Ireland called Prannie Rhatigan. She has written several books about seaweed. She is a mine of information on the subject. I did a seeweed foraging course with her years ago.
https://irishseaweedkitchen.ie, Heres her website. Drop her an email if you don't get answers on here. xxx

 

[Toddy]

@demented dale

Thank you