Plant Milks and Iodine: Recommendations for Vegans

Plant Milks and Iodine: Recommendations for Vegans

By |2017-09-28T20:53:12+00:00September 28th, 2017|13 Comments

The growth of the plant milk market is nothing short of amazing. Given the variety of options, it’s easier than ever to switch out cow’s milk for a more compassionate alternative.

But as these milks become more popular it’s natural (and important) to ask questions about how replacing cow’s milk with plant milks might affect nutrient intake.

In a study published this month in the British Journal of Nutrition, researchers looked at iodine content of plant milks in the United Kingdom. Iodine is a mineral needed for healthy thyroid function. Deficiency in pregnancy or early childhood can have lifelong effects on learning and development in children. In adults, chronic deficiency may affect mental function and it might raise risk for one type of thyroid cancer.

The researchers looked at 47 plant milks from 20 brands. They included milk made from soybeans, almonds, coconut, oats, rice, hazelnuts and hempseed. Except for the three samples that were fortified with iodine, all of the plant milks came up short compared to cow’s milk. It’s a legitimate concern because in both the UK and US, cow’s milk is a significant source of dietary iodine. This is largely due to farming practices since iodine is added to the diets of the cows and is also in the solutions used to clean the cows and milking equipment (which leach into the milk itself).

Aside from cow’s milk, the best sources of iodine are fish, sea vegetables, some commercial breads, and iodized salt. Although most plant foods contain some iodine, the amount varies depending on where the foods are grown, and it tends to be fairly low.


Iodine Recommendations for Vegans

Given the role that cow’s milk has traditionally played in iodine nutrition, it would be good for companies producing plant milks to fortify them with small amounts of iodine. Until that happens, vegan experts recommend either of two options for getting adequate iodine.

  • Include approximately ¼ teaspoon of iodized salt in your diet every day. Note that, although salt is iodized by law in Canada, it’s optional in the US and the UK (and it’s not commonly iodized in the UK) so you need to read labels. Sea salt may be iodized, but it usually isn’t. Kosher salt is not iodized. The salt used in production of processed foods is rarely iodized.
  • Or, take a small iodine supplement providing 75-150 micrograms of iodine every two to three days.

Some vegan advocates suggest regular consumption of sea vegetables as a source of iodine. This is probably not the best option, though, since iodine content of these foods varies widely. The British plant milk study included two samples that had added sea vegetables in their ingredients. Both were still low in iodine. In contrast, batches of soymilk fortified with the sea vegetable kombu were taken off the market in Australia and New Zealand several years ago because of dangerously high iodine contents. This doesn’t mean you shouldn’t consume sea vegetables, but it’s probably wise to limit them to a few servings per week and to not depend on them for iodine. Avoid iodine supplements that are made from kelp for the same reasons.

None of this is an indictment against plant milks or vegan diets and it’s certainly not some big cause for concern. A vegan diet simply represents a different way of meeting nutrient needs. It’s good to have the information that this study provides so that we can do what we need to do to ensure the health of vegans. I’m more than happy to sprinkle a little iodized salt on my beans if it helps the cows. (It also makes the beans taste better.)

For more on iodine in vegan diets see this article on Vegan Health.






  1. Scott September 29, 2017 at 2:23 pm - Reply

    I think this is a very important article that all vegans should read… because I think many do not consider iodine when they switch to a vegan diet. I do have to say though that I’m a little surprised by the amount of supplementation you recommend. Do you think 75-150mcg every 2-3 days is enough? That would average to 25-75 mcg/day. Where does the other 75-125 mcg come from? I take a 225mcg supplement 4 times a week which gives me about 129 mcg/day averaged. I figure I’m probably safe getting the last 21 mcg from food. I don’t use iodized salt because I’ve read that the concentration of iodine in iodized salt can rapidly degrade after several months of storage and I don’t use salt very regularly anyways. I’ve also read that 150mcg/day is the minimum you need to prevent a severe deficiency, but many believe that your body could really use more than that for optimal health. People who eat fish and sea vegetables regularly get much more than that and it doesn’t seem to be detrimental to health. With the low amounts of iodine in most plants, I just figured getting closer to that minimum level in supplements would be good.

  2. Phyllis Becker September 29, 2017 at 3:02 pm - Reply

    Thanks for this, Ginny, not only for providing valuable health information, but for giving me a possible excuse for my “mental function” decline. 😉 Because I have high blood pressure and therefore use very little salt in cooking, the supplement idea seems best for me. Off to the Food Co-op!

  3. Bruce Baran September 29, 2017 at 4:52 pm - Reply

    We don’t use table salt in our house, preferring to stay away from processed foods, and so use only natural salts, such as Himalayan or Sea Salts. So I add a bit of dried kelp to a seed and nut mix that I eat everyday along with my porridge as I’ve been told that kelp is the highest in iodine among sea plants, with nori being slightly lower. According to reports just one gram of dried seaweed usually provides 1-2 times the RDA of iodine.

    Of course I don’t measure it out exactly, but I’m getting probable close to 6 grams per week of the kelp.

    Good article Ginny, and I do wish the plant milk companies would start adding iodine to their products.

  4. Hayley September 29, 2017 at 9:26 pm - Reply

    Thank you so much for sharing this! I have been vegan for 20 years and have recently developed a thyroid condition, most likely connected to iodine deficiency.

    I never supplemented with iodine before now and because of books like The China Study etc, I also stopped eating table salt about 8 years ago. I’m also from the UK where salt doesn’t have to be iodized. I expect I was extremely low in iodine. I just didn’t realise I needed to supplement anything other than B12 and perhaps iron. I never properly researched it because I guess because I really wanted to believe supplementation wasn’t necessary on a plant-based diet, other than B12.

    I now take Dr. Fuhrman’s multivitamin, which covers most of what might be missing in a plant-based diet, and I will never neglect supplements again.

    I intend to always be vegan, as it’s important to me to do the least harm to animals as possible, and now I have my vegan multivitamin I’m confident my nutrient intake is covered! 🙂

    • Will October 3, 2017 at 2:38 am - Reply

      I’m thinking of taking Fuhrman’s multivitamin as well. Do you know if Ginny has ever commented on his products?


  5. Canastenard September 30, 2017 at 7:46 am - Reply

    Hello Ginny!

    For iodine my habit is to sprinkle some dried wakame on my dish once per dish every day, but that’s not you advise apparently. Do you think this habit may promote the risk of too little or too much iodine? Considering how you’re advising to “limit them to a few servings per week” I guess it’s likely the later.

    Maybe I might consider eating less seaweed, like only two or three times a day, and add some iodized salt to my diet. On the other hand it would make getting enough calcium a bit more of a challenge, as wakame is very rich in it and it’s the only nutrient I find challenging to get enough of on my vegan diet. I know I may use fortified plant milks and calcium set tofu but regularly buying them might be expensive – but that’s not the fault of veganism itself because in a world where dairy isn’t so prevalent I’m pretty sure fortified plant milks would be cheaper – although I plan to fix that by making my own homemade tofu made with calcium sulfate so it will on the long run be less expensive than buying them in store.

  6. dimqua October 2, 2017 at 3:13 pm - Reply

    Most kelp supplements manufactures claims that their products are reliable source of iodine. Is this just untruth?

  7. Martine October 10, 2017 at 8:10 pm - Reply

    Thanks for writing this! Iodine is an underrated topic. Here in Holland where I live, the bread salt is fortified with extra iodine, which causes problems for people who don’t like to eat a lot of bread (you have to eat 4-6 slices to meet the RDA). Some of the salt in the stores is fortified (not as much as the bread salt though), but this isn’t compulsory, so many salts don’t have iodine. I’m not a bread person, so I’ve decided to order the special bread salt and use that for cooking. Another good option is the Veg1 supplement by the Vegan Society which contains 25 mcg B12, 20 mcg vitamin D3 and 150 mcg iodine.

  8. julie handy October 11, 2017 at 11:52 am - Reply

    me and two friends have all the sudden become active vegans… its been approx 14 weeks now… i am feeling like im lacking something very important and as a woman who has always been relatively healthy and especially blessed with ((good jeans)), pedigree, that is desirable …??.. i believe it is iodine….???? i used to drink milk reg and the butter and cheese sour cream etc ….and now none of this….. this has got to be a jolt to our metabolism….and systems……
    please help
    we are not convinced as to how to get and maintain a steady intake of iodine and how to figure out what we can in corporate in our everyday cooking routines that will give us this this…??? i am even considering eating fish 4 or 5 times a month to keep a certain amount in my intake … cause kelp sound wrong and hard to swallow…no bt seriously please any in put would be greatly appreciated

  9. Robert October 31, 2017 at 7:50 pm - Reply

    Would a person with a soy allergy be allergic to all soy foods, fermented and non-fermented? I seem to tolerate soy milk very well. I would “like” to add natto or rather vitamin K-2 derived from natto, to my diet. New research on K-2 looks promising for bone and heart health.



  10. Moshe November 7, 2017 at 5:44 pm - Reply

    What is a Kosher Salt ?
    As far as i know Kosher regards to the kind of animals that are permitted to be eaten by the Jewish ‘Tora’ low.
    But Veganism is all about NOT eating animal products. What am i missing ?


    • RCubed January 21, 2018 at 11:29 pm - Reply

      Kosher salt is about size of the salt granular size

  11. Abi December 4, 2017 at 2:29 pm - Reply

    Thank you for this article, and all the others you’ve written! I’ve only just discovered your blog, but wish I had done a couple of years ago when I quit veganism due to malnutrition that I didn’t feel equipped to tackle. I’m almost back to a fully vegan diet and this time I’m determined to keep researching the lesser known aspects of nutrition, listen to what my body needs and ensure I don’t fail.Thank you 🙂

Leave A Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.