How Much Iodine Is Too Much?
In this article we mainly will discuss how much iodine is too much. To get a clear picture of this we want to look at specific iodine questions like:
- How much is too much?
- How much is too little?
- Testing to do to figure out if you have too much iodine?
- What problems can occur to your thyroid and your health in general from not enough or too much?
If this interests you, keep reading we're gonna discuss the details.
Why Iodine Is Important
We are going to discuss how much iodine is too much below, but first I want to give you a little background on iodine. Like why iodine is important and why this question is important to begin with. Iodine is an essential trace mineral that is important mainly for it's importance with thyroid function. When thyroid hormone is being produced one of the main components is iodine.
A large portion of the population was deficient in iodine in the early 1900s. and that caused thyroid problems. To solve this problem the government introduced iodine into the salt. It is now known as iodized salt. For the most part, this solution resolved most of the iodine deficiency in the United States.
More recently in the last 20 years or so more and more people are using natural salt like sea salt and Himalayan salt. These by and large do not have iodine in them not nearly to the degree that iodized salt does.
So if you are someone living in an area where there is low iodine in the soil, the foods will also be low in iodine. These people need to be more conscious of getting iodine from salt. Salt is not the only place we get iodine, however it is also in many seafoods. If you eat prepared foods on a regular basis most place use iodized salt to season with. So you are also getting iodine here. Iodine can also be found in cheese and some vegetables.
The RDA for iodine is around 50 micrograms per day and our bodies cycle through about one hundred micrograms per day. So you really don't need to consume a whole lot of iodine on a day-to-day basis. However your total body load, the total amount of iodine in your body is around 15 to 20 milligrams. This total body load will vary depending on your size. When you are deficient depending on how long you've been deficient, it will take your tissues and body a while to get your total levels back to 15 to 20 milligrams.
It may take months or even a year of supplementing with small amounts to get that level up because you don't want to do too much all at once. Your body and in particular your thyroid can be pretty sensitive to the amount iodine you're consuming. Too much iodine can disrupt the thyroid function just like too little can also disrupt the thyroid function. If you don't get it right you have increased chance of Hashimoto's Thyroiditis, higher rate of hyperthyroidism and also low thyroid or hypothyroid.
So we want to look at and sort out each one of these three different scenarios:
- low thyroid
- high thyroid
Ultimately we want to answer how you can safely take your iodine without causing more problems to your thyroid or body.
Research on How Much Iodine is Too Much
So in trying to figure out how much iodine is too much or how much you need, we want to look at some research looking at what happens when you take too much or don't get it quite right. If you are already significantly deficient and you start taking a moderate to higher doses of iodine it could cause problems. Specifically it can shift your body into thyrotoxicosis which is a severe hyperthyroid state. In this situation the person will have palpitations, anxiety, sweating, can't sleep, etc. It is a very uncomfortable state.
Another scenario is with autoimmune thyroid issues or Hashimoto's. Some people have very mildly elevated thyroid autoantibodies and may not even know they have it.
If they start taking iodine and it can worsen or exacerbate this problem. Sometimes people have antibodies but they are within the normal range and have a genetic susceptibility to Hashimoto's. For these people, taking iodine can induce Hashimoto's or increase the amount of antibodies that are being produced. So this begs the question, how much is too much?
There's a study done in the American Journal of Clinical Nutrition that looked to see what a moderate to high dose of iodine would do in people that have normal thyroid function. The study was done in healthy Chinese population and they were randomly assigned to receive different doses of iodine. They received 400 micrograms and up. The result showed that people getting the 400 micrograms started to see a decrease in thyroid function. Not all of the people did but about 5% of the participants that did get the iodine started to get a decline in the thyroid function. As that dose went up the amount of people that saw a decline in thyroid function also went up. The decline in thyroid function reached 50% at the 2 milligram dose. Usually the upper recommended dose for iodine is around eleven hundred micrograms . This is what's usually thought of as the upper limit. As this study illustrates you don't even need this much to potentially cause a problem.
To me it highlights the idea that you really want to know what your iodine levels are before you start taking it. Also to a certain extent you want to know what your antibody levels are.
Testing How Much Iodine is Too Much
With all the above in mind, most people that take iodine will be fine without causing long-lasting permanent problems, but it can. The simplest way to approach this is to get your iodine level checked before you start taking even small amounts. It's a good idea.
If your levels are normal, you could still take a small amount of iodine but you probably want to be more cautious. The standard test for iodine is called a serum plasma iodine test. It is done through a simple blood test that most labs can perform. The cash price is expensive so if you have insurance you probably want to use that. If your levels do come out low that means generally it is safe for you to take iodine. However depending on how low it is will dependent on your dose. You also have to consider how long your level has been low to understand how long you should continue taking it. You could simply run the test again periodically as well. Let's look at a few hypotheticals.
If your level is below 35 micrograms per liter, you want to start with a lower dose. It is probably best for everyone to start with the lower dose but these people specifically should start with a lower dose and titrate up. The reason is when you are low to being with you can trigger thyrotoxicosis (hyperthyroidism). You can go up to around that 1000 or 1100 micrograms but slowly over a four to six-week period.
Regardless of dose, you want to make sure you are re-checking your levels every four to six weeks. If you are lower then when you started (and this can happen), you probably need a higher dose. In other cases your levels may come out much higher. In this case you need a lower dose. Each time you check your levels you should avoiding the iodine for up to three days before you do the test. This will ensure that the dose that you took that day and subsequent days is not still in your system. This ensures you are looking at what the total body levels are. Eventually you don't want to be supplementing with the iodine every day . You are also trying to find that dose that is not going to increase your levels too much to negatively affect your thyroid function normal.
That should give you a deeper understanding of how much iodine is too much, how much is too little and how to supplement with iodine when you want to optimize a low thyroid function with iodine. Again iodine can cause problems if you get too much so make sure you're not overdoing it. If you have questions about your iodine supplementation submit a comment below. If you would like a customized plan on iodine and thyroid support, click on the link below for a free consultation to get started.