Menadione sodium bisulfite complex (synthetic vitamin K) is a common supplement in pet food. With the trend moving towards more natural, holistic and organic pet foods, this additive has become a controversial ingredient because of a misunderstanding of its purpose and its toxic effects in certain laboratory settings.
Menadione Safety Concerns?
It’s true that menadione has some cytotoxic effects, depending on its purity and dose. It is also being studied for its anti-cancer and anti-inflammatory benefits. Some concern comes from the fact that the product has a Material Safety Data Sheet that outlines some concerns and cautionary procedures when working with the substance. However, many common products have MSDS labeling. One reason there is a MSDS for menadione is because it’s typically handled in a setting where it is mixed to form other products; since there are some concerns, it gets reported on the sheet. The same is true for many ingredients of common products, like Vitamin C. It sounds scary when named ascorbic acid and has its own MSDS: “MUTAGENIC EFFECTS: Mutagenic for mammalian somatic cells. Mutagenic for
bacteria and/or yeast.” Whoa!
Check out calcium carbonate’s MSDS: “The substance may be toxic to kidneys. Repeated or prolonged exposure to the substance can produce target organs damage.” However, this really boils down to handle any purified substance with care; don’t inhale any powders; and too much of anything is bad for you.
In case the Group 3 Carcinagenic in the MSDS for menadione scares you, it’s simply the group for substances unclassifiable to carcinogenicity in humans. The following list the categories of possible carcinogens according to International Agency for Research on Cancer:
Group 1: Carcinogenic to humans
Group 2A: Probably carcinogenic to humans
Group 2B: Possibly carcinogenic to humans
Group 3: Unclassifiable as to carcinogenicity in humans
Group 4: Probably not carcinogenic to humans
To be clear, this is not proof that it is not carcinogenic, just that it has not been proven in humans. The data on causing cancer in animal cells is also a little muddied. It is understandable to be careful with it. However, it appears that eating grilled meat and potato chips is more likely to be cancer-causing.
Menadione in Pet Food
As for the use of MSBC in animal feed, it’s been around for a long, long time and there are no verified, well-cited studies that I can find that indicate it has ever caused harm when used in small doses as a food additive. I have emphasized the last part because injections of large-doses of synthetic Vitamin K can lead to issues; again, too much of anything is harmful. “The dose makes the Poison” – Paracelsus.
There are numerous claims from well-meaning, but misguided, bloggers, animal caretakers and those that fall for the “Appeal to Nature” fallacy. The way we arbitrarily classify products as “natural” or “artificial” is inherently flawed and we cannot let something as important as health be swayed by personal philosophy.
This is where an understanding of the scientific comes in very handy. Just wanting something to be true does not make it true. The more people you convince that something is true does not make it true. Anecdotal evidence can only be trusted so far. Actual research and experimentation should be the basis of any health, nutrition or science claim.