Black Foot Raw

Nutrition Lab

Nutrient Synergy and Antagonism


Our course on home prepared raw meals continues today. For the benefit of those joining for the first time, this is a short recap.


Declare war on moisture-deficient dry kibble.


Wipe out carbohydrates. They are not easily digested by your pet, causing a host of problems.


Obliterate legumes, nuts, seeds (We mean this literally. Seeds may have some value if you smash them into powder)


Annihilate plant fats and plant-based proteins (Again, literal, cause if you boil or steam the vegetables and then mash them into a puree, your pet may receive the benefits. This applies especially to fibrous and stalky, oxalate and lectin-rich plants from the deadly nightshade group)


No, we are not suffering from League of Legends overdose. Plant-based foods have no place in your cat’s or dog’s body unless they have been treated properly to remove their anti-predation chemicals and anti-nutrients otherwise they would be the ones declaring war in your pet’s body.


Also important if you’re using raw fish for omega 3, vitamin D and iodine, choose fish that are thiaminase free. If you’re unsure, cook the fish first. This will denature thiaminase so your pet will not lack thiamine deficiency.


Fruits can sometimes be useful as well, if you’re wary of the sugar content and if you avoid feeding them alongside your raw meats. Protein needs an acid bath. When proteins are consumed alongside fruit, it can potentially turn fruit into an alcohol ferment, creating a toxin that must be metabolised in the liver.



Balance (NRC, AAFCO)

It’s one thing fulfilling minimum AAFCO nutrient requirements, it’s quite another to balance the nutrients with one another.


Before we start, a few caveats:


To begin, you need to choose species-appropriate ingredients. It’s all very well that olive oil is high in omega-3 but they contain the ALA form which would not be converted efficiently into the EPA and DHA forms, the forms that your pets can process.


You also have to be wary of anti-predation chemicals and anti-nutrients from species-inappropriate foods. Sunflower seeds are high in vitamin E but they are full of anti-nutrients and anti-predation chemicals and would not be digested by a predator properly. In fact, it would come out of your pet the same way it went in.


Finally, we talk about balance. Balance comes from the proper ratios of nutrients in order that absorption is enhanced and not decreased by nutrient antagonism. AAFCO allows quite a large range between minimum and maximum requirements but toxicities may still arise when excess of one nutrient acts on another.


To understand the relationship between nutrients, consider this:


Providing calcium and phosphorus within safe and recommended limits without consideration for their ratio could lead to a calcium deficiency or excess which could lead to demineralization of the bone, heart problems, metabolic disruptions, abnormal growth and nerve issues.


You also have to know how much vitamin D is required for calcium absorption, along with the knowledge of how much the amount would be affected by the presence of vitamin A. Too much vitamin A cancels out vitamin D and vitamin D deficiency leads to loss of bone tissue, decreased immune function and even cancer.


Zinc and copper compete for absorption. Feeding a high copper-yielding liver like beef or lamb without enough zinc to correct the ratio will lead to zinc deficiency as well as copper toxicity. A double whammy. Without enough zinc, immunity will be compromised, diarrhea will be persistent, a problem common n raw fed dogs. Skin health declines, hair is lost and infections can result. Feeding a low copper liver like chicken or turkey will cause copper deficiency, leading to anemia, weakness, and fatigue.


Stick this on your fridge. You’re welcome.


Two relationships exist among nutrients, and as already expressed above, these are synergy and antagonism. The biggest concern is the trace minerals. These include iron, cobalt, chromium, copper, iodine, manganese, selenium, zinc, and molybdenum. Inhibited absorption of a trace mineral is often due to an excess intake of a particular mineral. One example was the craze over zinc. Many people jumped on the supplemental zinc bandwagon more than a decade ago and a host of problems resulted. For one, copper deficiency occurred. This is due to zinc depressing intestinal copper absorption.


Many others were experiencing mild zinc toxicity symptoms. High intake of one trace mineral decreases the intestinal absorption of another mineral. And this is not simply among the trace minerals. For example, a high intake of calcium blocks intestinal absorption of zinc. So even among macro minerals, consuming high doses of any mineral creates disrupt in balance. Further complications then follow at the metabolic level. Antagonism is experienced with an excess of one element. The excess interferes metabolically with the functions of another mineral. Even more, excesses contribute to disproportionate excretion of another mineral due to what is known as compartmental displacement. This occurs with zinc and copper, iron and copper, cadmium and zinc, and calcium, magnesium and phosphorus.



Left: Wrong way to expel excess zinc. Right: Right way.


Antagonism also exists among the vitamins. Vitamins A and D are naturally antagonistic while thiamine (B1) often creates an antagonistic action on cobalamin (B12). Some antagonism is indirect. One such example is iron’s antagonism on cobalt which is a vital component in B12, thus adversely affecting B12. If this is not complicated enough; hormones have an influence on nutrient absorption, excretion, transport, and storage. And conversely, nutrients have an influence on hormones.


Below is an example of a mere few nutrient antagonism:


  • Vitamin A + Vitamin D + Vitamin E
  • Zinc + Copper + Manganese + Iron
  • Calcium + Iron
  • Calcium + Zinc
  • Calcium + Vitamin E + Vitamin A + Potassium
  • Vitamin C + Copper
  • Vitamin D + Magnesium + Potassium


Below is an example of nutrient synergy:


  • Vitamin D + Calcium + Vitamin K + Boron
  • Iron + Vitamin C
  • Fat + Vitamin A, D, E, & K
  • Vitamin B6 + vitamin B12 + folate
  • Vitamin C + Vitamin E
  • Potassium + Magnesium + Calcium


Creating and providing meals with synergy is vital, but it is also necessary to know when antagonism may be beneficial. For example, many raw feeding pet parents are offering Vitamin A-rich liver on a daily basis. This can cause Vitamin D levels to suffer.


To create balance, providing a Vitamin D-rich meal in rotation while significantly reducing or eliminating liver will give Vitamin D levels a chance to rise. Feeding copper-rich beef liver with inadequate zinc levels will eventually lead to a zinc deficiency; thus providing a zinc-rich meal with a lower copper meal aids zinc absorption. Adding Vitamin C-rich foods or a food-source Vitamin C supplement assists the absorption of iron and is also beneficial with meals too rich in copper. Conversely, antagonism helps to prevent hypervitaminosis if a balance exists between antagonistic vitamins and minerals. Likewise, mineral antagonism also helps to prevent mineral toxicity.


While this may sound bewildering or even frustrating, I want to assure you that there is a straightforward solution. True balance can only be attained by varying meal ingredients, food combinations, and quantities of ingredients. This is why Blackfoot creates 7 recipes for our clients.


But if you’re up for it, these are a few points to take note when formulating your own raw diet:


  1. Calcium to phosphorous (Ca:P)- your goal is to achieve a 1.1:1 up to a 1.2:1 ratio.
  2. Zinc to copper (Zn:Cu)- I like to see this around 15:2.
  3. Vitamin A to vitamin D- I recommend a minimum of 5:1 up to 2:1 to ensure adequate absorption of D.
  4. Magnesium in relation to calcium- the NRC requires a mere 150 mg of Mg per 1,000 kcal. For optimal absorption and proper utilization of calcium, dietary magnesium and vitamin D levels must be optimal. This is critical. Having Mg at 100% to 200% is minimal. You can safely go upwards of 600% especially if your calcium is near or over 200%.
  5. Manganese in relation to Zn, Cu, and Fe- I prefer to maintain manganese levels around the same as copper and iron in relation to zinc.
  6. Selenium value (this will do the work of vitamin E)- selenium levels can be around 200% to 300%.
  7. Omega-6 fatty acids to omega-3 fatty acids- ideally, I like to see a 2:1 up to a 1:1 ratio
  8. Don’t neglect gut health, probiotics and collagen.


If you do most of these, you’ll not only have a pet that will live out its potential, you’ll also have a healthy pet that will be able to take care of you and provide you with company when YOU fall sick instead.


But the problem next would be what if, after you have painstakingly perfected your formula and come up with the theory of everything your pet refuses to eat some of the ingredients or turns out to be allergic to some of them?