Keeping dogs out of vets since 2011

How much iodine is safe for dogs?

iodine for dogs

Everything we assume we know about iodine in dogs is based on studies of conical flask iodine (iodide) and kibble-fed dogs. Like every other mineral (calcium, phosphorus, zinc, iron, magnesium, manganese, copper) the artificial, conical flask version is handled very differently by the body. For the aforementioned minerals, it’s because they are not chelated to a carbon molecule. This the body hates. Eg dogs absorb about 10% of the zinc or iron oxide fed to them, so they have to include LOTS in their mixes (and the AAFCO guidelines thus say to give LOTs, incorrectly – when you are using real food their “minimum” figures are excessive).

Iodine is different. Both conical flask iodine and food-sourced iodine is actually iodide (bound to something like potassium) as iodine on its own would actually kill you. But it turns out it’s the conical flask iodide that has the dramatic effect on the body because it’s not bound up with fibre which slows its delivery to the bloodstream.

Hence studies of dogs fed either kibble OR real food, when supplemented with conical flask iodide, develop thyroid issues.

Dulse, red seaweed

However, in a “real” iodide study where dogs were fed a whopping 15g of Ascophyllum per 1kg of food fed to dogs (this is more than double the dose of our Canident where we say a 35kg dog eating 1kg a day would be eating 6-7g max). The authors fed this for a month and found the “dogs showed good health conditions throughout the study“.

We shouldn’t be too surprised at this. We know Japanese folk are happily ingesting up to 8-20 times their RDA of iodide from seaweed and fish each day, with no problems (and those RDAs are not based on conical flask data, we wouldn’t be so foolish in human nutrition…but then, Ronald Mc Donald doesn’t write our nutritional manuals, for the large part). If anything, the Japanese derive great benefit from the practice, being among the healthiest and longest-living people on the planet.

The most recent test of our beloved tooth-cleaning, brown seaweed-based product Canident during summer (when it is expected to have its highest iodine content) reveals it contains 340mg/kg or 0.34g of iodine per kg of product (dry weight). This means, at its height, Canident is providing around 25 times (and up to 50 times in summer at the max dose) of the dog’s RDA for iodide, according to the conical-flask data AAFCO enthuses (a group most of us know to ignore for nearly every other nutritional statement…).

56 copy

So just to let our customers know, on the basis of the above and the fact we have never, ever heard of ill harm from consuming our products over the last decade, we will not be dropping the recommended feed amount on our label, until we know more.

On knowing more, we badly want to look into this – the thyroid impact on dogs fed a daily feed dose of seaweed. I’m chatting about this with a group. There is an issue here. You need to take bloods and that you are not allowed to do (outside of illness in the vets) as it falls under “experimentation”. The paperwork there is enormous, rightly (mind you, they can test dry food on 6 caged dogs for 6mths, is there anything crueler?!!).

So that’s where we are with the nutrient. It’s a tricky one and folk are very confused but I’m not going to shy away from the discussion. I see some manufacturers stating their iodine contents as incredibly low, I suspect to avoid having this discussion with their clients online. In many instances, including when looking at the figures stated by an industry leader, I’m not aware of any brown seaweeds that clean teeth have so little iodine, even in winter (unless it’s near a leaking nuclear power plant…I’m joking, of course…sort of).

I’m very open to discussion about this. If you have any ideas, I’m all ears. I want this answered as much as everyone else. Howeer, like most other conversations about correct or optimal nutrient inclusions for dogs, we are at sea (pardon the pun), lost in a melee of non-sensical dry food, George-Jetson-style nonsense.

For now, I’m going to see what info I can find on farm animals (pigs, chickens, cows, all get seaweed in great abundance…). I will keep you all posted what I find.

Share This Article



Need Advice?

1-to-1 Online Consultations

Should you need a little hand holding, I’m here to help. Consultations are typically 1 hour in length: 15 minutes to read your presubmitted questionnaire and prepare for your pet, 30-40 minutes with you directly via Zoom / Skype and 10-15 minutes to write your summary email, including all necessary tips and their diet plan. It also includes a follow up email should you need it.


"Finally! A well-written, well-referenced thorough examination of the raw dog food debate. A fantastic gift for your favourite veterinarian."
Dr. Karen Becker


For the most up-to-date advice, support, tips and ticks from Dr. Brady and his team, please subscribe below .

Related Articles

Fresh, good-quality protein for dogs with kidney disease
Raw dog food

Kidney failure in dogs – Could dry food be fuelling this disease? Part 2

In veterinary circles, the jury is still out on why so many pets today are suffering from kidney disease. Cats are twice as likely to get kidney disease than dogs (Veterinary Medical Database, University of Purdue) which largely rules out a genetic cause.  If genetics were solely to blame, then dogs should suffer more than

Read More »
Itchy dog DF dog
Raw dog food

Allergies in Dogs: Symptoms, Causes, Treatment & Remedies

Allergies in dogs is a big subject, and what’s more, the list of dog allergy symptoms can make you dizzy. Unfortunately, this can make the whole matter very confusing…in someone else’s hands! We at Dogs First are the dog allergy specialists, and below, in the most popular and most visited article on the site, we

Read More »
Turmeric for dogs
Dog Health

Turmeric For Dogs – Natures Most Powerful Anti-Inflammatory

The amount of info about turmeric for dogs is incredible. Unlike most herbal remedies, turmeric has a vast amount of high-quality scientific and clinical studies supporting it and testifying to its incredible anti-inflammatory properties.  The primary pharmacological bit in turmeric is called curcumin (that’s the deep orange colour). Clinical research has shown that curcumin is

Read More »