- ma 23 feb 2015, 15:48
Limiting B.AR.F. — is Ten Percent R.M.B.’s Enough?
Copyright © Ian Billinghurst
Commenting on a claim by a “barf nutritionist”
This article may be reproduced, but only in full and acknowledging its source.
The following question was submitted to me by Annemarie Rijnveld
Dear Dr. Billinghurst,
A “barf nutritionist” has made the claim that where RMB’s constitute the principal Calcium source in a raw food diet, 10% RMB’s will supply a sufficient amount of calcium.
Based on your knowledge and experience, would you agree with this claim?
Do you believe that a raw diet that includes 10% RMBs consisting of breastbones, oxtails, chicken wings, etc. will supply a sufficient amount of Calcium''? We would love to read your considered opinion on this important
With kind regards,
The full text of the “barf nutritionist’s” claim reads as follows …
''How much calcium, how much phosphorus?
Due to new findings in nutrition science, the calcium-phosphorus content of dog food has become quite controversial.
A few years ago, the recommended amount of calcium was much higher than today, with a Ca:P ratio of 1:1 - 2:1.
New insights published in 2006 NRC (National Research Council) state that an adult dog’s basal (minimum) metabolism requires 50-90 mg Ca /kg body weight /day.
Nowadays, it is claimed that the Ca: P ratio isn’t all that important; instead, it is important that the dog’s calcium requirement is covered.
If a dog is fed an adequate supply of RMBs, this will be the case.
In a raw food diet, the average Ca content of the bones can be assumed to be at least 2,500 mg/100 gr, provided the dog is fed a variety of RMBs (breastbones, oxtails, chicken wings, etc).
Thus, a raw diet that includes 10% RMBs (of the total ration) will supply a sufficient amount of Calcium''
The short answer is that ten percent RMB’s may be OK for an adult, nonreproducing canine, however, the question we need to ask is: “Does the programme as proposed fall within evolutionary norms for ALL canine life stages?”
And the only answer I can give is: “ I suspect not.
It may be OK for adult non-reproducing canines, but for growing canines and lactating canines, the level of calcium supplied will almost certainly produce problems related to a sub-clinical or even an overtly clinical calcium deficiency. While that is the answer to the question in a nutshell, I suspect most people will want a little more detail.
In making a more detailed answer, I will concentrate on the adult dog’s calcium requirements vs the calcium requirements of a growing pup.
This is the central dilemma that the “barf nutritionist’s” regime poses for the vast majority of dog parents. The other dilemma involves the calcium requirements of a lactating bitch; a dilemma for any dog breeder who chooses to accept the ten percent level as correct.
I will start by observing that mammalian bodies are far more complex than we can ever imagine.
Their labyrinthine homeostatic mechanisms enable mammals to adapt to a wide range of nutritional environments. Unfortunately, those mechanisms cannot overcome genuinely poor nutrition, as typified by fake industrial food.
However, when a nutritional programme is based on the principles of evolutionary nutrition, it works harmoniously with and recruits those homeostatic mechanisms to produce normal — healthy — functioning.
This is how evolutionary principles become the solution to most of the health problems we face today.
They answer the question: “What do I feed this body to make it function normally”.
This is the deceptively simple but powerful message I have sought to drive home for the last four decades, in my writings, my teachings. In essence, mammalian bodies respond to raw whole foods in an entirely different way to cooked and processed foods.
Their typical response is long-term health. However, when a raw food programme falls outside an animal’s evolutionary limits, that animal’s homeostatic mechanisms cannot cope, with less than perfect health being the eventual outcome.
So while it is mandatory to steer clear of non-evolutionary material such as fake industrial food (FIF) in order to produce best possible health, it is equally important, when feeding an Evolutionary or BARF programme of nutrition to make sure its composition falls within evolutionary limits or norms.
When we do this, those convoluted and mostly incomprehensible homeostatic and molecular biological mechanisms, will produce the healthy results we require.
Unfortunately, many people fail to understand or accept this simple truth.
Their fundamental doubt, their disbelief in evolutionary principles means they cannot accept that the mammalian body will respond “normally” to a nutritional programme that modern investigative science had no hand in forming. They cannot function without the “blessing” of peer-reviewed studies.
In developing his or her barf programme, our “barf nutritionist”, has fallen into this trap. He or she has not used evolutionary principles to form his or her evolutionary programme of nutrition.
Our “barf nutritionist” is not alone.
Too many raw feeders today feel compelled to walk the path dictated by AAFCO. What they fail to recognize is that AAFCO is the body that recognizes only fake industrial food as a legitimate way to feed a companion animal. It is this path our “barf” nutritionist” has taken as he/she seeks to answer the question “What percentage of the Evolutionary Programme of Nutrition should be devoted to Raw Meaty Bones (RMB’s).
When people use AAFCO principles to construct their RAW diets, they come to some amazing conclusions. Take the use of chicken wings as an example.
Having accepted the levels of calcium and phosphorus as proposed by AAFCO, many of today’s raw feeders will use those levels to decide how many chicken wings should be fed (as part of the over-all programme). Having made the appropriate calculations, people will arrive at diametrically opposing views.
Some of these people conclude: “Chicken wings are dangerous and should not be fed as they contain way to much calcium”, while others will state: “Chicken wings are a poor source of calcium and if you rely on them to supply calcium, you will produce a calcium deficiency”.
The point is, AAFCO standards are both irrelevant and misleading when constructing RAW Diets. And there is no body better equipped to make this point, than the AAFCO writers themselves.
Quoting from one of AAFCO’s official publications (2014) re … the fundamental goals and origins underlying recommendations for dog and cat food nutrient profiles, the AAFCO writers tell us that “… canine and feline nutrition experts … were charged … to establish practical nutrient profiles for both dog and cat foods based on commonly used ingredients.”
Note the words “based on commonly used” ingredients”.
Commonly used ingredients in fake industrial foods for pets include items such as …
§§ Meat and bone meal,
§§ Chicken By-product Meal
§§ Fish meal,
§§ Chicken liver meal,
§§ Peanut hulls,
§§ Soybean hulls,
§§ Vegetable oil … and so on.
These materials bear no relationship to the RAW, WHOLE and ACTUAL food materials our companion animals evolved eating.
Take for example, the protein-source items on that list; meat and bone meal, chicken by-product meal, fish meal and chicken liver meal.
All these “commonly used” animal source ingredients have been subjected to extremely high temperatures prior to being used to produce pet food. And they will be cooked yet again to produce the finished product.
This repeated heat assault means that those pet parents feeding FIF are serving a highly denatured product, where all components have reacted chemically with each other. These reactions produce a substantial loss of useful protein, a loss of vitamins and minerals, together with the production of compounds that are not only useless, but are in numerous cases toxic, mutagenic and carcinogenic.
It gets worse. Many people assume that because the word “chicken” appears on the pet food labels, this product contains a clean or pure combination of chicken flesh, skin and bone. Sadly, this is a long way from the truth. We know this because of the words “by-product” and the word “meal”.
The inclusion of the words 'By-product' in the descriptor means that the 'chicken' used will contain a high level of indigestible material; it will be a mix of entrails, feet, bones and heads — heat treated of course.
The inclusion of the word “Meal” in the descriptor means that this material, following cooking and drying, is finely ground. The reason for grinding is to disguise the masses of cooked bone that has been added to the product.
Cooked bone is very cheap, which is great for the manufacturer. Unfortunately, it severely damages the nutritional value of the finished product; cooked bone contains mostly indigestible protein.
The calcium it contains acts differently to the calcium in raw bone. In growing animals this upsets the calcium phosphorus balance (ratio) and the way calcium is absorbed.
This contributes to the bone and joint abnormalities such as hip and elbow dysplasia, as seen in the larger breeds that routinely dine on these materials.
If we give all of this some thought, by including the words “based on commonly used” ingredients”, AAFCO is acknowledging — perhaps unwittingly — that their standards do not relate to the materials used to construct RAW WHOLE foods.
AFFCO’s standards relate or apply ONLY to the OVER cooked, highly DENATURED, HIGHLY INAPPROPRIATE (in a biological/evolutionary sense) and DANGEROUS ingredients used to make fake industrial foods. (What they don’t acknowledge is the damage caused by the products they oversee).
That same AAFCO publication also tells us that that for many essential nutrients, including many minerals (such as calcium), there is insufficient data to establish a minimum requirement. They note the problem of bioavailability or digestibility, which can range — depending on the mineral — from 10 to 100 percent.
They cite numerous factors affecting mineral availability or digestibility including: specific source of the mineral, the concentration of other specific minerals in the mix and/or ingredients use to make the pet food as well as the mineral status of the animal (in terms of the mineral in question).
In short, AAFCO’s recommendations for mineral levels in pet foods are a nutritional compromise; an arbitrary figure — sitting somewhere between the two extremes of digestibility — and employing numerous assumptions basically, they are having a GUESS.
And remember, these recommendations are for foods where all the ingredients are highly compromised in terms of freshness, wholeness etc.
These “Guesses” are NOT for products based on evolutionary principles. I should also point out that in relation to calcium for growing animals, AAFCO recognizes the need for increased levels in the diet compared to adult requirements. In saying this, they are of course one hundred percent correct.
Furthermore, these increased levels of calcium apply whether the animal is eating FIF or BARF. I point this out because, as already mentioned, this fact is vitally important in relation to our “barf nutritionist’s” statement.
The next point I need to make is that AAFCO recognizes two ways to substantiate the nutritional adequacy of a pet food.
The FIRST WAY is by ensuring the product has a nutrient profile consistent with AAFCO standards (for each of the nutrients that AAFCO recognizes as essential).
THE SECOND WAY is for the product to pass the AAFCO feeding protocols.
On this point, AAFCO MAKES IT CLEAR that where a product is substantiated as nutritionally adequate by feeding trials, that product does not necessarily have to meet the AAFCO nutrient profile standards.
That latter FACT is important and highly relevant to anyone wishing to feed raw. The point is, we already know that any properly formulated BARF product, when subjected to AAFCO feeding protocols, will be found to be nutritionally adequate.
And THIS WILL BE SO FOR ALL LIFE STAGES.
This brings me back to our question of Evolutionary principles vs FIF principles.
What must be understood is that the nutrients in MODERN fake industrial foods behave very differently in the body compared to nutrients derived from RAW WHOLE FOODS.
This means the standards imposed on fake industrial foods by AAFCO bear very little relevance to the standards that RAW Whole Foods must adhere to. And note in this regard, AAFCO (probably unwittingly) allows for this by accepting a food as complete and balanced where feeding trials prove it to be so.
And as already pointed out, ALL properly constructed BARF or EVOLUTIONARY programmes of nutrition cannot help but pass such tests.
The next issue that needs to be discussed is the difference between the Calcium-phosphorus ratio of a product or diet vs the total amounts of calcium and phosphorus in that diet.
I am making this point because too many people make the mistake of equating the two. The Ca:P ratio tells us the amount of calcium relative to the amount of phosphorus — in the diet.
What it DOES NOT tell us is the ABSOLUTE AMOUNT of calcium (or phosphorus) in the diet. This means that diets with the same Ca:P ratio can have vastly different levels of calcium and phosphorus.
Let me give you an example. Suppose we have two dog food samples — 100 gm of each. We will call them Dog Food A and Dog Food B.
100 gm of Dog Food A contains …
§§ Calcium = 1 gm
§§ Phosphorus = 1 gm
100 gm Dog Food B contains …
§§ Calcium = 10 gm
§§ Phosphorus = 10 gm
Dog Food A and Dog Food B each have the same Ca:P ratio (1:1)
HOWEVER, Dog Food B has ten times the levels of Calcium (and phosphorus) as Dog Food A.
This brings us to the question of the calcium (and phosphorus) ratios and requirements of growing dogs vs adult dogs. Adult dogs can maintain adequate calcium levels in their body, even where the levels of calcium in the diet are quite low. The adult dog will simply take enough calcium from its food to maintain both its bones and the correct calcium levels elsewhere in its body.
What we are observing here is the adult dog maintaining its calcium levels as opposed to building new bones. Of course there is a point, below which there will be insufficient calcium in the diet to maintain these calcium levels; an all-meat diet is an obvious example.
Please note that all canine diets, whether based on FIF or BARF principles, have plenty of phosphorus. This is because they are high in protein, which is always high in phosphorus!
Look with me now at someone feeding a raw food diet to an adult dog.
Let’s assume that the diet currently being fed includes a level of RMB’s at around the five percent level. In this case, the calcium to phosphorus ratio might be 1:20 (one gram of calcium for every twenty grams of phosphorus — or may be even a wider ratio — 1:50 perhaps).
In general, we would not expect this to cause a problem. There will be enough calcium in the diet to maintain both skeletal calcium levels and provide for all other bodily functions dependent on calcium.
The dog will simply extract — from the food — the calcium it requires.
In other words — and getting back to the question under discussion — the “Nutritionist” you are quoting is quite correct — but only for adult dogs.
And that is the point to notice. My worry is that people will see this recommendation and think that it applies to growing puppies or lactating females.
It does not!
The calcium requirements for growing canines are quite different compared to adult canines.
The growing canine is NOT maintaining its bones;
The growing canine is FORMING or BUILDING its bones.
To build its bones requires high levels of calcium in the diet AND a ratio between CA & P where the levels of calcium and phosphorus are roughly equal (1:1) or where there is a slight excess of calcium over phosphorus — which can be a ratio of around 2 parts of calcium to one part of phosphorus (2:1).
The BARF Diet is able to do this beautifully; however, there are still limits when it comes to growing canines.
Although evolutionary nutrition is very flexible in terms of how many raw meaty bones we need to supply, in my experience, the lowest we should go for growing canines is 20% RMB’s and even then I prefer it to be higher.
That is why I recommend between 30% and 60% RMB’s in the diet (where there is an equal amount of meat and bone in those RMB’s).
This level of RMB’s provides an amount of calcium and a ratio of calcium to phosphorus, which assures us of healthy bone growth in pups.
Please also note that at this level, there will be NO HARM TO AN ADULT DOG — thanks to those homeostatic mechanisms mentioned earlier — where both the adult and the juvenile each take what they need and leave the rest.
However — and this is important — those homeostatic mechanisms will only function fully normally, when the calcium is supplied as Biologically Appropriate Raw Food. (An evolutionary nutrition principle)
To help you understand this principle, consider the following …
Compare two pups, one eating a diet with 10% RMB’s and another being fed a diet containing 60% RMB’s.
If those diets were formulated to have the same Ca:P ratio (quite simple to do), the diet with 60% RMB’s would have around six times the amount of calcium as the diet with 10% RMB’s.
We will now follow these two pups as they go about their daily business. I am particularly interested to look at their stools. We will find that both of these pups form stools that turn white in the sun.
This is because MOST of the calcium present in the RMB’s passes through the pup’s digestive tract unabsorbed.
This is important.
As scavengers, our dogs have an evolutionary history of bone consumption—this is outlined in my writings and forms a basic principal of evolutionary nutrition for dogs.
As scavengers, our pups have evolved requiring bones as their preferred and ideal source of calcium (in the context of a raw evolutionary programme of nutrition of course!). If insufficient bones are supplied, they will suffer from a calcium deficiency, which is related to an incorrect calcium-phosphorus ratio (too much phosphorus), with resulting health problems, including joint and skeletal ill health.
If sufficient bones are supplied they will take the calcium they need and develop in a healthy way — and that includes their skeleton and joints. The take-home point is that because growing canines — as scavengers — have evolved eating a diet high in bones, evolutionary principles dictate that is the best way to feed canine pups.
They respond to the calcium in bones (as hydroxyapatite) in a biologically appropriate way. All they need is plenty of RMB’s. Those RMB’s must not be limited.
We must NOT follow the principles involved in producing fake industrial food to guide us in this important task.
Canines have evolved in such a way that in order to form healthy bones and joints, they must eat plenty of raw meaty bones as pups.
This is a simple but profoundly true principle of evolutionary nutrition. Of equal simplicity and truth is the fact that as adults, canines will do fine with or without such high levels
Unless we are talking about a lactating female
When constructing raw food diets for dogs and cats, it is essential to base what you do on evolutionary principles.
Yes, you can look at modern nutritional science, but make sure it is relevant to what you are doing.
It often isn’t and may lead you astray when it is based on research involving fake industrial food. Always follow the Evolutionary principle if there is any doubt.
Also consider the principle known as Ockam’s razor. This principle states that among competing hypotheses, the one with the fewest assumptions should be selected.
Other, more complicated solutions may ultimately prove correct, but—in the absence of certainty—the fewer assumptions that are made, the better. In other words, the simpler the better and nothing could be simpler than following the principles of Evolutionary Nutrition.
It has been my experience that for pups to develop a healthy skeletal and joint system, they must have a diet that contains around 30% to 60 % RMB’s (the latter preferably).
By supplying less than that to a growing puppy, we risk the dangers of a badly formed skeletal system — amongst other calcium-related problems!
So, if someone tells you that a raw diet that includes 10% RMBs (of the total ration) will supply a sufficient amount of Calcium'', just remember that this is absolutely fine for an adult dog, but there is the strong possibility that it will be a diet that is deficient in calcium in the case of a young dog.
This may well be disastrous for that dog’s growth, most particularly its bone and joint health. It will also produce problems for a lactating bitch and her pups, but that is a whole other story.