Some call menadione a necessity. Others reject it as a dangerous toxin.
So, what exactly is it? And why is it being used to make certain dog foods… and not others?
Menadione is the man-made version of an essential nutrient commonly known as vitamin K. Menadione is itself referred to as vitamin K3.
But K3 is just one of five known versions of vitamin K. The three most common ones related to the subject of dog food are…
- Vitamin K1 – the natural type found in green leafy vegetables
- Vitamin K2 – the kind produced by bacteria living inside a dog’s gut
- Vitamin K3 – menadione, the man-made “synthetic” version
Vitamins K1 and K2 are considered “natural”. That’s why, in addition to being fat soluble, they’re also chemically ready to be used by the body… just as they are.
Now, menadione (K3) is different. Not only is it not fat soluble, this synthetic vitamin must first go through a dog’s built-in process known as “alkylation”… before it can be used by the body.
So, What’s So Important About Vitamin K?
Well, the vitamin is used by the liver to manufacture various clotting factors… chemical compounds designed to stop or control bleeding.
So, how much vitamin K does a dog need?
Well, according to one authority… not much. A dog needs very little Vitamin K per serving to sustain life… just one part per million1.
The controversy over menadione centers around two opposing views.
Menadione… a Nutritional Necessity?
Supporters2 look at menadione as a necessary additive… an important nutritional supplement dog food companies should feel compelled to include in their product recipes. Defenders argue in favor of the use of menadione because…
- Natural vitamin K may lose its potency during processing
- Intestinal disease may prevent gut bacteria from making the vitamin
- Not all manufacturers include green leafy vegetables in their recipes
Advocates also claim menadione should be considered safe because toxic levels are a thousand times greater than the recommended daily dose.
So, many companies choose the only approved vitamin K supplement readily available… menadione.
Or a Dangerous Toxin?
Opponents3 see menadione as only a precursor to the vitamin’s more natural versions. They cite studies that make some rather disturbing claims. Critics like to point out that menadione…
- Causes toxic reactions in liver cells
- Weakens the immune system
- Induces allergic reactions
- Causes abnormal break-down of red blood cells
One company selling menadione warns its human buyers that menadione is “toxic to kidneys, lungs, liver, mucous membranes. Repeated or prolonged exposure to the substance can produce target organ damage.”4
A Wolf in Sheep’s Clothing
By the way, it can be very difficult to spot menadione. That’s because manufacturers frequently list the vitamin in rather complex fashion.
The cryptic phrases below depict some of the more common chemical variations of menadione that can show up on an ingredients list5.
Sorry for the crazy words. I was a chemistry major in college and I too find them just about impossible to read…
- Menadione sodium bisulfate
- Menadione sodium bisulfite
- Menadione dimethylprimidinol sulfate
- Menadione dimethylprimidinol sulfite
- Menadione dimethylprimidinol bisulfite
- Dimethylprimidinol sulfate
- Dimethylprimidinol sulfite
- Dimethylprimidinol bisulfate
- Vitamin K supplement
And watch out! You might even come across menadione hiding behind innocent little phrases like one that refers to it as… “a source of vitamin K activity”.
The Bottom Line on Menadione
So, how should you approach products that include menadione in their list of ingredients?
Well, my take has always been to err on the side of safety.
Until there is an authoritative opinion on the subject of menadione, I recommend that shoppers give preference to menadione-free products whenever possible.
- National Research Council of the National Academy of Sciences ↩
- Aldrich PhD, Greg, http://www.PetFoodIndustry.com ↩
- Contreras, Sabine, http://www.DogFoodProject.com ↩
- Menadione sodium bisulfite, ScienceLab.com, Houston, TX ↩
- Contreras, Sabine, http://www.DogFoodProject.com ↩
{ 7 comments… read them below or add one }
This is very interesting information. I thought I would check out this website recommended by the diabetic support group that I am a member of as I am trying to find a good quality dry dog food for my diabetic Lab. I have research and research, pretty my relentlessly. They are either to high in fat, to high in carbs, of just plain CRAP. And I’m learning about the vitamin K in sheeps cloating. I just noticed that the food I was feeding my labs indeed had the (source of vitamin K activity). I took them off of it as it was brought to my attention about an FDA warning about the food making dogs ill and that it was said it have actually killed several dogs. I’m not willing to risk my dogs health so for now I have them on Chicken Soup Senior. This is a good quality food but I’m not really all that happy with the carb content. In the meantime I am still on the lookout for an even more appropriate food for my Calah. Thanks for such an informative site.
Brenda… you are right about how difficult it is to find this important information for diabetic dogs. I intend to address this neglected subject in detail in future articles and publications. The info should be able to help you find products that are significantly better for diabetic dogs like Calah. For now, try reading my recent article that shows you “How to Calculate the Hidden Carbohydrate Content of Any Dog Food.” Thanks for writing.
It appears that the controversy is unfounded to me.
http://community.dog.com/forums/p/71119/553912.aspx
I have looked at all ingredients in Paul Newmans Own adavnced organic fromula dog food and can not find this Vitamin K 3 or any of the names it could go by that wree suggested by your report. Could it be possible that they took it out when they found it was not good for dogs and if so you need to change an update your report because this dog food appears to be one of the better ones from my reveiws of many and my only one concern is the soy not vit k3 as I do not see it in there anywhere.
Hi Kathy… when I read your comment I re-visited the Newman’s Own Organics website and found our “dashboard” matched the company’s published ingredients list exactly. If you’re getting your information directly from a package, the company may not have updated their website. In any case, thanks for calling this to my attention.
Hi, I just purchased a bag of back to basics honesty chicken & was reading your review. You talk about Menadione in the food but I do not see it listed on the bag. Nor do I see it listed under any of the other names you listed. Could they have removed it? I do not want to open the bag and feed it to my dog untio I am sure.
Thank you,
Nona
Hi Nona… Although it may not mention menadione on your dog food’s package, the chemical can still be found on the product’s ingredients list at the Back to Basics website (which is the source of our data). For a definitive answer to your question, you may try calling the company at 800-219-2558. Hope this helps.