Where do you get your iodine from? The answer may depend on where you are, or in other words, how the country you're living in has chosen to add supplemental iodine to the nation's diet. The Standard American Diet, for example, will provide your iodine via regular table salt whereas in the UK, it's supplied in fluctuating quantities via cow's milk from supplementation of the cow's feed.
Bearing in mind that we're, quite rightly, being advised to reduce our salt intake and that consumption of dairy milk is on the decline, are these measures appropriate in today's world? We think not. But since modern soils supply inadequate quantities of iodine for plants to grow in, what's the solution? A good response is seaweed.
The various types of seaweed typically contain various levels of iodine, and indeed a good range of other minerals. Many of us are familiar with nori ..the one made into sheets for making sushi rolls. It's a good source of iodine without being too potent a source as is the case for kelp, unless consumed in very small quantities. Kelp can be so high in iodine that ¼ tsp or less a day may be plenty. An option that provides more iodine than nori but less than kelp is one of our favourites, namely dulse. A tsp of dulse flakes is a good rough guide for maintaining an appropriate level of iodine. Another favourite of ours is wakame which, in addition to its iodine content also supplies a decent amount of the Omega 3 fat EPA, which in turn is a precursor for the all important DHA. After all, these fats aren't manufactured in the bodies of fish, the fish eat omega 3 rich sea vegetables and then pass them on to whatever or whoever eats the fish.
There are a couple of things to consider with respect to consuming seaweed. They are inherently highly nutritious and beneficial foods, but human interference in the oceans has led to varying levels of pollutants, not least heavy metals such as mercury, and some sea vegetables take up larger quantities of these than others do. The same applies to arsenic which is simply unacceptably high in some seaweeds. The ones we have highlighted here - nori, dulse and wakame are some of the seaweed varieties that are less affected by such contamination, such that the benefits typically outweigh the low levels of contaminants.
There is a final consideration perhaps especially for vegans. It's good news with a cautionary twist. Unlike almost all land-grown plants which are inevitably grown in today's depleted soils, seaweed can supply some vitamin B12 ....if it is fresh! This is not the case for dried sea vegetables, meaning B12 will still need to be sourced elsewhere. If, like us, you do consume seaweed and are thinking of having your B12 levels tested, we recommend asking for a homocysteine test or a methylmalonic acid test as the dried seaweed contains B12 analogues which appear as B12 on a standard blood test, but these analogues are not the active form of the vitamin and they may then mask a deficiency.
So in conclusion, there is a good range of seaweed options in most health food stores and increasingly even in supermarkets meaning that we can obtain iodine and other beneficial nutrients without compromise.
This German language link provides some good supporting information about various sea vegetables. The mineral values table provides easily understood data even if German is not your language: https://proveg.com/de/ernaehrung/lebensmittel/algen-naehrstoffreicher-salat-aus-dem-wasser (We should add here that we do not consider hijiki an ideal choice due to high levels of arsenic).
A research paper on the fluctuating quantities of iodine in UK dairy milk: https://www.sciencedirect.com/science/article/abs/pii/S0946672X18307466