Iodine Deficiency: 4 Odd Reasons This Epidemic is Killing Brain Power

Imagine a child who could have over 13 IQ points higher intelligence from a simple change in the pregnant mother: welcome to iodine deficiency.

In the worst regions of the world a simple iodine supplement could raise the IQ of children by a standard deviation (a lot!) when given to the pregnant mother [1][2]. This is the lowest hanging fruit…

…but plenty of healthy adults struggle with iodine deficiency as well.

The changes in diet have led to more common symptoms of iodine deficiency for men and particularly for women. There is an abundance of evidence that iodine is an essential mineral, which many people are simply neglecting in their diet (especially with the war on salt).

Iodine Benefits: What is This Nutrient’s Purpose?

The benefits of iodine are mostly related to thyroid function and specific hormones. Iodine is a trace mineral extracted in high quantities in China and Japan specifically for health purposes. Without iodine, our bodies cannot manufacture specific hormones that we need for adequate physical and mental function.

According to many organizations, iodine deficiency is one of the leading causes of cognitive disabilities in the world. One thyroid expert named Dr. David Brownstein found that over 96 of his 5,000 tested patients were deficient in this essential mineral [3].

As we will describe below, there are many reasons people are deficient in iodine and it is a global health problem. In fact, the World Health Organization estimates that 72% of the world’s population is deficient, creating all manner of brain health problems [4].

Iodine Deficiency Symptoms

The major iodine deficiency symptoms are related to a disease called cretinism, which is an extreme form of iodine deficiency whereby fetuses in a pregnant mother are mental retardation or simply lower intelligence as a result [5].

This is what the World Health Organization has set out to solve (especially in the third world) because it robs children of capabilities before they leave the womb. This naturally translates to changes in schooling success. In one study (published in the book Poor Economics), children who were born with adequate iodine in the gestation period stayed in school longer because of their added ability to learn.

Of course, this doesn’t even consider the effect of iodine deficiency on the person (particularly women) who may experience any number of the following side effects:

  • Depression
  • Headaches
  • Memory problems
  • Fatigue
  • Brain fog
  • Weight changes

Almost all of these are signs of hypothyroidism, which can be related to an iodine deficiency and clearly negatively effects cognitive abilities [6]. One study looked at 15 different cognitive tests and found evidence of poorer performance on many in those who had hypothyroidism (often directly related to iodine deficiencies).

As great as remedying an iodine deficiency might be, it is possible to go overboard. One study followed iodine consumption and how it could negatively impact cognitive performance when it gets to be too high [7].

Iodine Deficiency and Cognitive Defects

From the existing research, one might reasonably extrapolate that taking iodine supplements after birth or throughout life is inherently valuable for improving mental performance. This may not be so.

According to self-experimenter and blogger, Gwern Branwen, a meta-analysis suggests that except for one outlier study, most evidence points to no benefits of iodine supplements after birth [8]. It would seem that most of the best results (or at least highly leveraged results) come while the baby is in utero.

Iodine Deficiency Test

The best way to test iodine deficiency is with a crude patch. This iodine deficiency test can help detect levels in a crude way that can give you direction if not a true depiction. An iodine deficiency test will usually come with a small square patch, which is placed on the inside of the forearm, thigh, or abdomen to see the results.

In the morning you will inspect the painted area and if the color remains, iodine is adequate. If color is done, there could be an iodine deficiency.

A better way to test iodine deficiency is through a blood test of thyroid stimulating hormone. This should be pretty standard on blood tests, but may be something to add if not. Try to hit a reference range between 0.27 – 4.2 uIU / ml.

This might not mean much to you now, but after the test is over you will see that if you’re in the range, there is a good chance you are not deficient in iodine.

Iodine Supplements and Food Options

There is no need to go directly to iodine supplements in order to fulfill this essential nutrient. There are plenty of foods that have iodine, though it is best to stick with one as often as possible: seaweed.

In Japan and China, countries with some of the largest seaweed consumption, the iodine deficiency is the lowest. Seaweed is a great way of getting high quantities (sometimes 1000%+ daily recommended value) of natural iodine.

Other food sources of iodine include cod fish or dairy products like yogurt and raw milk. With enough of these foods in your diet, it is pretty easy to get iodine in adequate doses.

Iodine vs Nootropics

Understanding iodine deficiency is a perfect example of how our unique individual biochemistry and needs influence what kind of supplementation we should have. Developing hypothyroidism and problems with hormones as a result of iodine deficiency will wreak havoc on your life and health.

By paying attention to these biological factors (rather than nootropics for improving aspects of cognition) we can do more good with less invasive drugs. These are what we call “easy wins” and in the case of iodine, it may not even be a supplement required to provide that win.

References (Click to Expand)
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