Mercury found in seafood may not be a risk – choosing selenium rich species of fish/seafood is key!

We do not recommend fish or seafood for any/all cats, or for dogs with a history of urinary/renal issues or renal disease/insufficiency.

We also do not recommend using fish or salmon oils to provide omega-3s in the diet.

SFRAW’s Focuses on Utilizing Whole Foods: When it comes to nutritional safety, balance, bio-availability/absorption and stability, we promote and rely upon the use of unadulterated, wholesome, fresh/raw whole foods in nearly every circumstance. Unlike most other prepared raw foods, SFRAW Formulas and Grinds do not contain added vitamins or minerals, but they do contain a variety of whole foods that provide these nutrients in a safe and balanced manner.

For some whole foods, traditional preparations or handling may enhance or increase the nutritional quality of foods. The nutritional and health benefits associated with altering/gently “processing” whole foods via traditional preparations/handling, should be considered on a case by case basis because every food can/will react differently to traditional handling such as: soaking, mashing, sprouting, low-heat extraction (bone broths), fermentation, aging, and combining with other foods (especially herbs and spices) etc.

The best sources of beneficial omega fats for dogs/cats come from high-quality animal fats and low-contaminant seafood: An incredibly important (and sometimes overlooked) component of a well-prepared, properly planned fresh foods diet is the balance of essential fats (omegas) in the ingredients used. We provide omega-rich and balanced foods in two ways:

Number one: SFRAW uses only 100% grass-finished, wild-foraged, pasture-raised meats/poultry, eggs, dairy in all of our Grinds & Formulas. Sourcing is KEY and handling is important to provide a starting strong platform for nutritional balance and safety.

Number two: Omega balance and incorporating omegas with the most health benefits in our Formulas is also accomplished through the addition of 5% whole raw anchovies, sardines, oysters. For the seafood-free Rabbit Formula, we use duck egg yolks with added pasture-raised duck or pork fat. The seafood species we have chosen are rich in beneficial omega3s and are known for being sustainable, well-managed, low-contaminant and lower in mercury, which makes it safer. These selections of small oily fish/oysters provide additional important nutrients, too — such as B-vitamins, vitamin E, zinc, and, most importantly when it comes to seafood – adequate selenium!

Better Understanding Risk: Selenium and Mercury InteractionsBecause of media coverage and urgent government warnings, we realize that some may have concerns regarding the mercury levels found in seafood. In addition, the controversial, problematic safety report from the Clean Label project, may have erroneously boosted concerns about this ingredient use in pet foods.

So, here’s where you need to know: the mercury found in these seafoods may not be a concern at all! This is because the selenium found in adequate amounts in these very same foods provides a “neutralizing” effect on the mercury found in these foods. (side note: isn’t nutrition interesting and isn’t nature just so amazing!?)

The resources linked to/quoted below will provide you with the information that you need to make a decision you feel comfortable with for your animals. While mercury toxicity is certainly a significant risk that should be avoided, especially in pregnant women, babies/children and animals, the mercury (methylmercury) found in the most commonly consumed seafood is in effect “neutralized” because these species also contain adequate levels of selenium.

Recent evidence indicates that assessments of mercury exposure and tissue levels need to consider selenium intakes and tissue distributions in order to provide meaningful risk evaluations.  –Mercury toxicity and the mitigating role of selenium by Berry MJ1, Ralston NV; 2008 Dec.

Learning more about this important issue should put you much more at ease and perhaps even change your mind if you have avoided utilizing seafood in your animal’s diet. The resources linked to/quoted below will provide you with the information that you need to make a decision you feel comfortable with for your animals.

For a look at the issue overall without making any clear conclusions or recommendations, this blog post, Can Two Wrongs Make a Right? Mercury and Selenium in Fish, provides a nice review.

For a local take on the issue, the Monterey Fish Market has a great blog post, Mercury and Selenium in Seafood.

IMO, this industry prepared PDF actually provides an accurate and concise overview of the risks involved, Selenium and Mercury Fishing for Answers.  I’ve quoted this for the takeaway message:

Selenium is the key to understanding mercury exposure risks. Scientists discovered that if a body has sufficient selenium to maintain proper function, the risks from mercury are mitigated.

It is essential for our health that we understand the real risks of avoiding fish versus the potential risk of mercury exposure from eating fish. Since ocean fish are excellent sources of selenium, they provide nutrients without repercussions from mercury exposure.

Chris Kresser has several excellent blog posts on the topic worth your review including: 5 Reasons Why Concerns About Mercury in Fish Are Misguided. Here’s an excerpt:

#1 (reason): Studies of mercury exposure in fish consistently ignore the important role of selenium
We’ve known about the role of selenium in preventing mercury toxicity for at least 45 years, with the first research report on this topic appearing in 1967. (1) Since then several studies have shown that selenium consistently and predictably counteracts the adverse effects of mercury exposure. (2)

How does selenium do this? Exposure to mercury is harmful because it deactivates special selenium-dependent enzymes—called selenoenzymes. <snip> Our current understanding is that mercury interferes with selenonzyme function by binding to selenium. In fact, mercury cannot cause harm until it occurs in high enough amounts to inhibit a significant percentage of selenoenzyme activities. Mercury is only harmful because it binds to selenium and prevents it from performing its vital roles in the brain.

As long as you are eating fish that contains more selenium than mercury, the amount of selenium in the body will always be in plentiful excess of mercury. That means that these essential selenoenzymes are never inhibited to a meaningful degree. Fortunately, the vast majority of fish most people consume have more selenium than mercury. The exceptions are pilot whale, shark, tilefish, king mackerel and swordfish.

Unfortunately, the well-documented protective effect of selenium is consistently ignored in both the medical community and the media when reporting on potential harms from fish consumption. This is almost certainly causing harm, as it has led to advising pregnant women and young children to eat less fish, when we should instead be telling them to eat more.

Kresser has covered this issue a few different times, and this is a great podcast he has available on this very topic: The Truth about Toxic Mercury in Fish

VitalChoice is obviously a biased source for information regarding this issue, so I hesitated to include this, but they have provided such an nice, well-researched overview of the concerns and current information on this important topic: Mercury-Fighting Mineral in Fish Overlooked in Heated Debate Advocacy groups that raise red flags about mercury in fish fail to mention seafood’s built-in safeguard.

Health Benefits of Selenium: The widely protective and numerous beneficial effects selenium has on the body, and the specific interaction it has with mercury exposure from all sources, is important to understand. Learn more about selenium and how it can be used to “detoxify” the body of mercury exposure from all sources (not just seafood) here. There’s also good information provided in this article: Highlights from the 200 Years of Selenium Research Conference

Well sourced, low-contaminant (low-mercury, low-PCBs, etc.), sustainable whole fresh/frozen raw sardines, anchovies, mackerel, smelt, cod, herring, oysters, clams, mussels, salmon, trout, halibut, flounder — all provide different levels of omega3s, plus important vitamins & minerals in the canine diet. We feel strongly that relying on these select seafood choices is a far safer and healthier option over fish oil supplementation (or the use of other oils such as flax). We sell a variety of outstanding options for this including frozen salmon roe and Marine Phytoplankton.

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