World Health Organisation guidelines advise a safe maximum daily intake of 1000µg and the British Health Food Manufacturers Association advises that food supplements should not deliver more than 500µg per day. The UK Government adheres to a RDI / (recommended daily intake / amount) of 150µg whilst in America this is 200µg. There is no international agreement on a maximum safe daily intake.

“In all species studied the tolerance is high relative to normal dietary iodine intakes, pointing to a wide margin of safety for this element” (12).

Common kelp tablets widely (and very cheaply) produced as iodine supplements are a less balanced source of iodine than Seagreens® and none has organic quality certification. Seagreens® Food Capsules and Seagreens® Iodine+ Capsules are entirely free from additives or agents, and may be the only pure vegetable source on the market.

They are approved by the Vegan Society. Market research prior to introducing Seagreens® Iodine+ Capsules in 2003 found a leading brand of (not organic) kelp tablet sold as “a natural source of iodine” and “suitable for vegans” contained 0.225mg (225µg) of iodine, 264mg of cellulose and calcium phosphate ‘fillers’, plus 11mg of silica, magnesium stearate and stearic acid added for manufacturing convenience. No product of organic quality was available.

Whilst soil mineral deficiency may even exclude iodine altogether (a micro- or trace mineral), the widespread use of (unchelated) iodine in animal feed, milk and dairy products have made these the main sources of iodine in the British diet, disadvantaging vegetarians. Whilst UK government statistics estimate an average adult daily iodine intake of 200µg, average daily intakes of 80µg may not be uncommon in vegans (13). Seagreens® may also have a regulating effect in hyperthyroid.

Several papers provide a comprehensive review of the research on this subject (53-59). Iodine has been shown to reduce radioactive iodine-131 absorbed by the thyroid. In Norway pharmacies are obliged to maintain stocks to supply their local population in case of nuclear accident.

Iodine, of which Seagreens® is an ideal natural source, has been noted by researchers in connection with the incidence ADHD and ADD in the children of iodine-deficient mothers in Western industrialised nations (124, 125).

Seagreens® original blended Seagreens® Food Capsules typically provide 422µg per gram (per recommended daily use of 2 x 500mg capsules - 221µg per 500mg capsule). Alternatively, where economy is a prime consideration, Seagreens® Iodine+ Capsules are a less expensive single 500mg vegetable capsule for daily use delivering 350µg iodine per day but with a less significant input of the other related nutrients. The difference between these capsules is that the Iodine Capsule contains a single wild Wrack seaweed with a high iodine content, where the Food Capsule is a deliberately low-iodine mix of Seagreens® seaweeds allowing all the other nutrients to be ingested at higher levels.

The marked decline in dietary iodine during the past fifty years included the removal of iodate from bread during the 1980s, when it was largely replaced by the goitrogeneous additive, bromate. This has since been associated with an increased incidence of obesity, diabetes, and hypertension as well as thyroid and breast cancer (118).

Recognising the deficiency of iodine and the excess of sodium in the nation’s diet, the latter caused largely by its addition to our daily bread, Seagreens® approached a number of bread manufacturers in Britain and elsewhere, inviting them to replace salt with Seagreens® Culinary Ingredient.

Foremost among those who adopted the idea is Artisan Bread of Whitstable in Kent, England, a biodynamic bread producer established at about the same time as Seagreens®. Artisan has gained national recognition for the quality and goodness of its product range which includes a bread for almost every special diet.

See also Obesity

See also Thyroid and Iodine Deficiency