Foods with iodine and the Paleo Diet.
The Paleo Diet is very popular among CrossFit participants and is often advocated by CrossFit Boxes (gyms). It consists of basically meat, vegetables and some fruit and excludes grains, beans, dairy products and limits or excludes salt. This may pose a nutritional risk. Dairy and iodized salt are the major sources of iodine in the US. Since the Paleo Diet reduces foods with iodine, people following the Paleo Diet may end up limiting their iodine intake.
CrossFit and iodine.
Most iodine is lost in urine. New research indicates that people who drink a lot of water may excrete more iodine than other people. Iodine may also be lost in sweat. There’s probably no need to talk about Crossfit and sweat.
Why is iodine important?
Iodine is an essential nutrient. The major sources of iodine in the US are iodized salt and milk and sometimes bread (depends on how it was made). Iodine is needed to make thyroid hormones. In adults thyroid hormones are needed to maintain metabolic rate. Without enough iodine people cannot make enough thyroid hormone. Without enough thyroid hormone people become hypothyroid. Signs are low energy, slow, often gain weight, and develop poor blood lipid profiles which can lead to cardiovascular disease. Iodine is especially important for pregnant women because thyroid hormones are also important for fetal brain development. Children whose mothers did not have enough iodine can end up with a lowered IQ and behavioral problems. It is very important that pregnant women eat foods with iodine. Breastfeeding women should also consume foods with iodine.
What are some foods with iodine other than salt and dairy?
Milk and iodized salt are the major sources of iodine for most people in the US. If you are following the paleo diet, alternative foods with iodine are sea vegetables (seaweeds, kelp) and sea food. Some multi-vitamins also contain iodine, but many do not. If you rely on vitamin supplements check the label and see if they contain iodine. Watch what you buy. If you use salt, check the label and see if it contains iodine. Sea Salt, by the way, will not contain iodine unless the manufacturer added it. The iodine in sea water is lost during the process of evaporating it down to salt. Lastly, and as always, don’t go completely overboard and take more than you need. Total intake for a day should be about 120 to 150 micrograms. If you are pregnant or nursing you may need more. But don’t take too much. Taking too much increases your risk of harming your thyroid and creating more problems.
Johner SA, Shi L, & Remer T (2010). Higher urine volume results in additional renal iodine loss. Thyroid : official journal of the American Thyroid Association, 20 (12), 1391-7 PMID: 21034227
Zoeller RT, & Rovet J (2004). Timing of thyroid hormone action in the developing brain: clinical observations and experimental findings. Journal of neuroendocrinology, 16 (10), 809-18 PMID: 15500540