No, Table Salt is Not A Good Substitute for Potassium Iodide

Today’s latest mobile phone SMS scare advises people to stock up and eat table salt, which usually has added iodine, as a “healthier” way than potassium iodide pills to counter radiation exposure. Does this make sense? Actually, no, it doesn’t — in order to get the equivalent 130mg dose of potassium iodide that is usually recommended for adults during a radiation crisis, a person would have to eat 250 tablespoons of iodized table salt each day. Sea salt has much less iodine, so that’s an even worse option.

So, everyone, let’s please not drive ourselves into a salt-induced city-wide heart failure. Please try to inform your friends who may be hoarding table salt, or who are spreading these SMS messages today.

However, I do think, in terms of general health, that eating seaweed and kelp products is already a healthy idea, and since they have a bit of iodine, then it certainly cannot hurt and will also prevent you from being naturally iodine-deficient. But again, if there were a real emergency, you certainly could not rely on kelp alone, nor kelp tablets, as an adequate substitute to potassium iodide pills/liquid. Again, it’s the same reason — you’d need hundreds of plates/pills of kelp each day to get the same protection.

I got this information from an American website which also sells supplements. I would prefer a more objective source, but their articles are written well and quote research articles for verification. Here is their blurb on table salt:

From the Salt Institue:

“U.S. salt producers use potassium iodide at a level of 0.006% to 0.01% KI.”

According to Morton Salt:

“Each 1/4 teaspoon serving of Morton Iodized Salt (1.5 gram weight) contains 130 MICROGRAMS of Potassium Iodide.”

Thus, to achieve an intake of 130 MILLIGRAMS of Potassium Iodide (what one KI adult dose tablet contains) would require ingesting 250 teaspoons or over 5 cups of iodized salt per day! Don’t even think about it! (Morton Lite Salt Mixture comes in lower yet, at only 90 MICROGRAMS of Potassium Iodide per 1/4 teaspoon!)

Sea Salt is an even worse ‘option’. Iodine per Kilogram of sea salt is about 3 mg. You’d be looking at over 33 kilograms of Sea Salt a day to achieve the amount of iodine in a 130 mg dose of KI! Hardly an option!

A 6-ounce portion of ocean fish only contains about 500 MICROGRAMS of iodine. Some specific seafoods, portion size and their iodine content in MICROGRAMS: Mackerel 150g 255 mcg, Mussels 150g 180 mcg, Cod 150g 165 mcg, Kipper 150g 107 mcg, Whiting 150g 100 mcg, Fish fingers 75g 75 mcg, Scampi 150g 62 mcg, Herring 150g 48 mcg, Prawns 150g 42 mcg, Sardines, canned in oil 150g 35 mcg, Trout 150g 24 mcg, Tuna 150g 21 mcg.

Well, you can do the math here! More fish per day would be required than most eat in a year!

Kelp Tablets…hardly. Solgar Kelp Tablets, for example, contain only 225 MICROGRAMS of iodine! (Fortunately, it is also available in a 1000 tablet bottle, unfortunately though, you’d need to be swallowing 442 of them per day and likely not wander too far from a bathroom!)


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2 thoughts on “No, Table Salt is Not A Good Substitute for Potassium Iodide”

  1. Do we have data on lethal doses of table salt? Would someone risk severely harming themselves (by disrupting sodium levels in the blood) if they were to ingest 250 tablespoons of salt per day?

    I guess there isn’t much risk of that. People may be stupid enough to think table salt is a radiation treatment, but they are not stupid enough to kill themselves with it.

  2. Actually, many people have died from eating too much salt. The condition is called hypernatremia, and it’s common in infants, the elderly and sometimes even from drinking too many sports drinks! Here’s one review:

    “Fatal hypernatremia from exogenous salt intake: report of a case and review of the literature.
    AUModer KG, Hurley DL
    SOMayo Clin Proc. 1990;65(12):1587-94.

    Hypernatremia is a common electrolyte disturbance, most often caused by volume depletion. Hypernatremia due to sodium excess occurs less frequently, and fatal hypernatremia solely from ingestion of table salt is rare. We describe a 41-year-old man who had seizures and hypernatremia after ingestion of a supersaturated salt water solution intended for gargling. He had consumed approximately a third cup of table salt (approximately 70 to 90 g of salt or 1,200 to 1,500 meq of sodium). His initial serum sodium concentration was 209 meq/liter. Hypotonic fluid therapy was given to provide free water and to correct the hypernatremia gradually. Our patient, however, failed to recover from the initial insult and died 3 days later. Review of the literature revealed 10 adult and 20 pediatric cases of hypernatremia attributable to exogenous intake of salt. The type of therapy (fluid or peritoneal dialysis), the type of fluid used, and the rate of correction of hypernatremia did not influence survival. The age of the patient and the initial serum sodium concentration were the most important prognostic indicators. Both very young patients and those with lesser degrees of hypernatremia had a better rate of survival than did other patients. In addition, our review illustrates the surprisingly small amount of salt that can cause severe hypernatremia and the danger of using salt or saline as an emetic.”

    And more from many doctor’s favorite website, UpToDate:

    SODIUM OVERLOAD — Acute and often marked hypernatremia (in which the serum sodium concentration can exceed 175 to 200 meq/L) can also be induced by the administration of hypertonic sodium-containing solutions. Examples include accidental or nonaccidental salt poisoning in infants and young children, the infusion of hypertonic sodium bicarbonate to treat metabolic acidosis, hypertonic saline irrigation of hydatid cysts, and massive salt ingestion as can occur with the ingestion of a highly concentrated saline emetic or gargle [32-36].

    The hypernatremia in this setting will correct spontaneously if renal function is normal, since the excess sodium will be rapidly excreted in the urine. This process can be facilitated by inducing a sodium and water diuresis with a loop diuretic and then replacing the urine output solely with water [7]. Too rapid correction should be avoided if the patient is asymptomatic; these patients, however, are less likely to develop cerebral edema during correction, since the hypernatremia is generally very acute with little time for cerebral adaptation. (See “Treatment of hypernatremia” and “Manifestations of hyponatremia and hypernatremia”.) Even with optimal therapy, the mortality rate is extremely high in adults with a serum sodium concentration that has acutely risen to above 180 meq/L [35]; for reasons that are not well understood, severe hypernatremia is often better tolerated in young children [33].

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