The one mineral you lose with sweat that you should know about. Iodine and athletic performance
Did you know that you can lose even 50% of iodine with sweat during 1-2h of exercise? That’s a lot! Surprisingly, nobody is even talking about it! What’s important, iodine deficiency can actually impair your athletic performance. Minerals that we hear about as essential electrolytes that should be replenish during or after exercise are sodium, potassium, calcium and magnesium. Let me explain why you should pay more attention to Iodine. Especially if you are active and train on regular basis.
Electrolytes lost with sweat and impact on energy Exercise and sweating have lots of benefits if it comes to endorphin release and getting rid of excess toxins from your body. Unfortunately, you are also excreting valuable nutrients. As long as sodium is usually easy replenished, it may not be the same for potassium and iodine. Potassium plays pretty important role in heart function and blood sugar regulation. On the other, iodine has broader spectrum and can influence your whole metabolism, stamina, muscle and joint health. Also your cognitive functions and mood. This is because iodine is the key building block for thyroid that controls lots of processes in your body including energy production! No matter if you are professional athlete or just regular gym goer, well-functioning mitochondria and optimal energy production is the key!
Daily iodine requirement increases with amount and intensity of exercise Your daily minimum iodine requirement is around 150mcg for an adult. However, from functional medicine perspective this amount is underestimated and accounts only for iodine needed for thyroid. Iodine is also used by other body tissues like breasts and ovaries. Interestingly, the highest concentration of iodine in the body is actually found in breast tissues, not in thyroid! Anyway, studies showed that during exercise you can lose on average 40-50mcg per 1h session. It depends on intensity and humidity or temperature of course. You will probably lose more iodine running in a tropical country comparing to a place with less humidity.
Thyroid dysfunction in athletes Athletes in general are more prone to thyroid suppression because of the amount and intensity of exercise they are doing. Female athletes are especially more sensitive to hormonal changes comparing to men. Women are also more prone to hypothyroidism which is low thyroid function. It was shown that intense exercise can decrease T3 levels which is active form of thyroid hormone. Low T3 levels can impact your metabolism and energy production. Iodine is one of the key nutrients needed to make enough of thyroid hormones. That’s why I wanted to emphasise how important is to ensure appropriate iodine intake. Especially when you train on regular basis as significant amount of iodine is lost with sweat. Also, iodine is not in that many foods. If you are vegan you have even more limited choices. The most abundant iodine sources are seaweed and certain fish as haddock and cod. Impact of thyroid on athletic performance Thyroid hormones regulate the size and performance of muscles. This is important not only in terms of building your strength and stamina but also recovery from the trainings. Underactive thyroid can also impact your:
Heart and the amount of blood your heart can pump. Low or slow blood circulation means less oxygen delivered to the muscles which could reduce your performance.
Bones – thyroid also regulates your bone formation. Poor bone metabolism could contribute to more brittle bone and bones more prone to breaking.
Insulin sensitivity. Thyroid regulates your metabolism. If its sluggish, it may be harder for your body to get glucose from the blood delivered to your muscles. In absence of glucose (i.e low carbohydrate diet or training in a fasted state), it will be more difficult for your liver to make glucose from fatty acids.