In a study that looked at the iodine status of various Norwegian population groups, researchers studied nearly 300 people across a wide range of ages. Their group included 44 vegetarians, 19 of whom were also vegans.
The study’s participants were asked to complete food diaries, which were then assessed by researchers to calculate the iodine content of the foods and beverages consumed. They also reported any iodine intake they happened to be getting from supplements.
In addition to totaling participants’ iodine intake based on the information provided by their food diaries, the researchers measured their urinary iodine concentrations and correlated them using the figures calculated from the food dairies.
They found that vegans had the lowest probability of sufficient iodine intake from both food and supplements at 14 percent. Children, on the other hand, were the group with the highest likelihood of getting enough iodine. All of the groups except for vegans got most of their iodine (up to 60 percent) from milk and yogurt, while the vegans mainly got it from supplements.
Why do you need iodine?
Iodine is essential for biological functions like growth, development and metabolism. Those with iodine deficiencies can end up with thyroid nodules, goiters, thyroid cancer, menstrual problems, and headaches. Children and pregnant women are particularly vulnerable; pregnant women who do not get sufficient dietary iodine could give birth to children who have lower intelligence levels.
The recommended daily allowance of iodine in the United States is 150 micrograms for adults, 220 micrograms for pregnant women, and 290 micrograms for those who are breastfeeding.
Iodine is found in foods like milk, fish, and certain cheeses, all of which are not consumed on a vegan diet. Vegans can get iodine from sources like Swiss chard, spinach, asparagus, turnips, and kelp. Smaller amounts of the mineral can also be found in walnuts, brown rice, almonds and lima beans. Iodized salt is not considered a good course of iodine because it has poor bioavailability, which means your body cannot fully absorb it.
Unfortunately, it is possible to take too much iodine, so it’s important to be careful that you don’t overcompensate with supplements. In the Norwegian study, 12 people were found to be taking excessive amounts of iodine, and the three people whose levels were the highest were all taking kelp supplements.
If you do choose seaweed supplements, in addition to ensuring you don’t overdo it, you should also be sure you get them from a trusted source as many of the commercial varieties are contaminated.
Symptoms of excessive iodine include stomach pain, diarrhea, a metallic taste, headache, runny nose and nausea.
Iodine deficiency surprisingly common
It’s not just vegans who aren’t getting enough iodine; according to the National Health and Nutrition Examination Survey, more than half of the population does not get sufficient levels of iodine. In addition to poor diets, it’s also being blamed on farming practices that deplete iodine and other minerals from the soil. In addition, toxic chemical exposure can hurt your body’s ability to absorb it. The mineral is essential for a healthy immune system and has anticancer properties, so it’s important to make sure your intake is within an acceptable range.
See Iodine.news for more headlines on iodine.
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