Can vegans be low on iodine? 

We all know how healthy our way of eating is. The benefits of plant foods are well known.

But there is evidence that many people, including vegans, can be at risk for iodine deficiency.
Therefore contrary to popular belief, it isn’t protein we need to be concerned about when going vegan.

The risk of lacking some micronutrients, such as B12 and Iodine can actually be higher.

How much iodine do we need? 🤔
Adults require about 140 mcg to 150mcg. During pregnancy, this needs to be increased.

Let’s have a closer look at this mineral:
Iodine is an essential mineral that is required for healthy thyroid function. It’s used by the body to make thyroid hormones.

These hormones control your metabolic rate, meaning it sets the rate at which your body uses energy when it is resting.
They also help your brain and body grow and develop.

Iodine is found mainly in seafood and in some countries, in dairy.
Dairy farmers use it as one of the feed components and in the past for its disinfectant properties for teats. As vegans, we obviously strike-off seafood, crustaceans, and dairy as a source.

And plant foods, (other than some microalgae), are a rather poor source because try as they might, they can’t absorb enough of it because our soil contains low levels. Therefore our vegetables, fruit, grains, nuts, seeds, and legumes can’t be relied on giving us the correct recommended daily intake.

The local Vegan Society writes: 
“There is no easy way of knowing how much iodine is in plant foods.” Each batch tested shows a different result depending on the soil quality.
Like 1 cup of strawberries may have 5mcg but the next batch tests at 13mcg.

Plus if you eat too many foods that can limit the uptake of this mineral, you can fall short of the recommended daily intake.

Which foods can limit the uptake of iodine?
The main culprits are the vegetables that contain goitrogens. For instance RAW Brussel sprouts, kohlrabi, turnips, rutabaga, radishes, cabbage, kale, and cauliflower.

But only when eaten in crazy huge amounts.
However, good news: when they are cooked, they are fine.

There might also be other foods that could interfere with iodine absorption, such as soy foods.
In 2020 an observational study cautioned that women who have borderline thyroid health may wish to reduce their intake of this healthy food.

Those on thyroid medication may wish to read up about soyfoods taken close to taking medication.
The British Thyroid Foundation has some info for you about this. Scroll down to the info on soya.

Even if at your last blood test your thyroid hormone levels were slightly better than borderline, you could be experiencing some problems usually associated with a deficiency.

One of the most damaging effects of iodine deficiency is on the developing brain during foetal and early postnatal development.  An iodine-deficient diet during that stage of life can cause mental retardation. And an iodine deficiency can also cause miscarriage.

But let us look at iodine deficiencies in adults.
It can cause your thyroid to not function at its optimal levels, and therefore you may experience:
Low mood, anxiety
Fatigue and weakness
Changes or abnormalities in the menstrual cycle
Dry skin and brittle nails
Elevated LDL cholesterol
Dry, flaky skin
Hair loss
Intolerance of cold temperatures
Slowed heart rate
Weight gain not otherwise explained
Are supplements safe?
Yes, but only in the right doses.
There are different types of iodine supplements; some are too high in iodine and can be potentially harmful. Please ask your health care practitioner what the right amount is for you.

Like kelp. Some batches show up close to toxic levels.
For instance, a type of kelp called kombu can have up to 3000 mcg per individual seaweed sheet and can damage the thyroid when used on an ongoing basis.
Other than for individuals receiving iodine for medical treatment, the recommendations for the ‘Tolerable Upper Intake Levels’ varies between countries.

The UK mentions a conservative 500 mcg maximum intake for the average person.
Other countries mention a max of 1,100mcg a day.

So what can we do to ensure thyroid health and sufficient iodine intake?
1) Keep an eye on your overall wellness. If you aren’t feeling OK, please speak to your doctor and get some thyroid health tests so you know where you stand.
2) Eat a variety of plant foods but never eat too much of one particular food. Vary your diet.
3) Consider taking a vegan multivitamin with 150mcg iodine.
4) Or, just like Dr. Greger from Nutritionfacts, eat two nori sheets a day. However, we can’t be sure they contain the amount of iodine.

Read up here on further iodine info. It’s a Fact Sheet for health professionals.
It’s an eye-opener when you scroll down to the low iodine content of our plant foods.
Many contain only 1mcg  or zero mcg per serving.

I take a daily supplement of 150mcg because I definitely don’t wish to fall short on this essential mineral. 😍


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