Iodine: why, what kind, recommended amounts and how to supplement.

For quick reference later – Iodine recommendations –  RDA -150 ug (micrograms) – Ketogains recommended starting at .5- 1 mg up to 3 mg with 1 mg maintenance+ 200-400 ug selenium


(for those without pre existing thyroid conditions, not recommended to supplement iodine if you have existing thyroid conditions until further research is conducted, proceed at your own risk)

Iodine is a vital nutrient for every process in the body. Iodine was added to table salt to prevent goiter from deficiency but the amounts in it are hardly enough. The RDA of 150 ug is just enough to prevent goiter. It is not likely that this is enough considering 90% of dietary iodine is lost via urine and 52 mcg can be lost during 1 hour of sweating. Simple math shows us that an intake of at least 500 mcg daily is a good starting point for those beginning a ketogenic diet without previous thyroid issues. Currently there is not enough information on hand to create a recommendation for those with previous thyroid issues, proceed at your own risk. More links below so you can educate yourself.

During adaptation, keto flu often induces a “brain fog”. If you experience this brain fog, it may be worth your time to experiment with higher doses of iodine. These doses have not been clinically tested but there is a lot of anecdote regarding it’s efficacy. You can check your thyroid levels but realize that the ranges are only an average of “healthy” people, usually on a high carbohydrate diet, changing carbohydrate levels impacts the way the thyroid functions and therefore the panels can be off yet you’re entirely asymptomatic. More info here on how carbs impact thyroid function.

For adaptation, we recommend starting with 150 mcg and increasing by 500 mcg every 1-2 weeks. Do not increase your dose more than 1 mg/week. Too much iodine increase at a time can worsen symptoms and inflame the thyroid, according to Many have taken their dose into 100 mg+ range but most only need to go to ~12 mg daily for full effect. 12 mg is a safe recommended maintenance dose.

Here is the protocol for supplementing iodine, doses, types, additional supplements, and other important information.

More info on additional supplements (//

Alongside your iodine intake, it is recommended to take other nutrients to help balance and absorb iodine into your system.

  • Vitamin C – 2,000 – 5,000 mgs / day optional – supports the symporters and assists as an antioxidant to detoxing. However, on a ketogenic diet, vitamin C requirements are very low, almost nonexistent. Though vitamin C can help absorption of iodine so it won’t hurt to be without, but having it can help.
  • Selenium – 200 – 400 mcg / day – needed for detoxification and thyroid hormone creation. This supplement is the most important to take with iodine. Never skip the selenium, it can damage your body to be without it. Chris Kresser discusses selenium here and here
  • Salt – ½ tsp / day – supports adrenals, binds to bromide and assists in removal, supports symporters (sodium iodine symporters or NIS). If you experience detox effects or other malaise, increase sodium intake immediately to relieve the symptoms.
  • Magnesium – 400 – 1200 mgs / day – critical for over 300 enzyme reactions in the body. Also important to help maintain a “calm energy”. But you should be taking this already.
  • Optional – ATP CoFactors -1 tablet 2x / day – when individuals continue to feel fatigued or have autoimmune thyroid disease this product can assist in increasing ATP (energy) within the cells. Riboflavin and no-flush niacin. These are not likely necessary on a ketogenic diet, due to reduced need for these nutrients.

Finally, the above is mentioned for brain fog during adaptation, however many adapted keto dieters continue to supplement iodine for life. There is growing evidence that it is not possible to get enough iodine via whole foods due to lack of iodine in dirt and iodine uptake inhibitors in the diet and environment. We recommend at least experimenting with iodine at low doses and building carefully, especially from an athletic perspective, due to iodine loss in sweat.

More links:

This post, like all other posts are updated as new information is presented. Feel free to contribute evidence in the commentary.