Pet Nutrition
 | ||||||
Achieving a Calcium to Phosphorus Balance
Calcium to Phosphorus balance is essential to the development and maintenance of a strong and healthy skeletal structure. If a living creature is not getting enough Calcium in its diet, its body will seek to obtain it from within - from its bone mass. Too much Calcium, on the other
hand, can also cause health issues. It is not difficult to supply this balance.
While some nutritionists and physicians state that the optimal balance is a ratio of 1.1:1 – the Calcium slightly higher than the Phosphorus, other individuals claim that for the carnivore, the Calcium to Phosphorus ratio can be as high as 2:1- twice as much Calcium than
Phosphorus. In his article, Balancing the Calcium/Phosphorus ratio in a raw diet for dogs (2003), Mogens Eliasen, PhD, states that 1.2:1 Calcium to Phosphorus ratio is ideal (about 7% to 10% of the raw meat meal as bone), but leaves room for a slightly higher amount of Calcium in the overall diet as long as it is not in excess.
The following list charts the Calcium and Phosphorus found in various boneless meats and how much Calcium should be added to get the Calcium higher than the Phosphorus and keep within what is considered balanced ranges:
Raw Boneless Meat Calcium* Phosphorus* Difference Calcium needed
(per lb) (estimated)
Beef Chuck 81.6mg 798mg 716mg 730 to 760mg
Chicken Breast 49.6mg 781mg 734mg 750 to 780mg
Lamb Ground 59.0mg 762mg 703mg 720 to 750mg
This list clearly demonstrates how feeding only boneless meats would cause an unhealthy imbalance in this important Calcium to Phosphorus ratio.
Taking into consideration the difference in Calcium to Phosphorus listed in the table above, adding about 800mgs of elemental (absorbable) Calcium per pound of boneless meat is sufficient. However, organ meat is very high in Phosphorus and would require substantially more Calcium to achieve balance; just one of the reasons it is not recommended to feed organ meats in large quantity at one time. See example below:
Raw Boneless Meat Calcium* Phosphorus* Difference Calcium needed
(per lb) (estimated)
Chicken Liver 35.2mg 1329mg 1293mg 1300 to 1350mg
There are three ways people who feed their pets a raw diet accomplish a balance of Calcium to Phosphorus when feeding boneless meats or eggs:
1. Mixing the raw boneless meats with ground Frames (carcass with meat
removed). Preferred because it is the most natural form of Calcium.
2. Adding ground eggshell. (Calcium Carbonate – an antacid) Highly acidic
stomach acids allow our pets to safely digest raw meat. Calcium
Carbonate reduces stomach acid. We suggest eggshell with cooked eggs
or occasional cooked boneless meats only. Pure Bone Meal Calcium is the
safer choice for raw boneless meats and raw eggs.
3. Adding any other Calcium supplement. Least favorable because
supplements may contain other ingredients that dogs and cats are
sensitive to.
Bone is the most natural source of Calcium for our carnivorous companion animals. The Calcium to Phosphorus ratio in bone is 2.5:1 (two and a half times more Calcium than Phosphorus.)
Carnivores were biologically designed to eat whole-prey animals; the meat, fat, organs, and bone. Our pets can easily digest and absorb the Calcium and other nutrients found in bone.
When you feed primarily raw with proper amounts of bone added, you will only need to consider giving your pet added Calcium when you are serving them boneless meats, organ meats, or egg.
Tripe is a boneless meat, but it is naturally balanced in Calcium and Phosphorus and therefore does not require additional Calcium. Tripe supplies excellent protein and unadulterated enzymes and probiotics to your pet’s diet.
You don’t have to be exact with every meal. About seven to thirteen percent (7% to13%) bone in the overall diet is a good target range. With a variety of food, a balance within range, over time is fine. Keep in mind: the minerals found in processed pet food are part of a large mix of overly processed synthetic minerals. Some commercial pet foods contain far too much Calcium causing growth spurts in growing puppies and resulting in life-long joint issues. With all the pet food recalls with supplement potencies too high in this and too low in that we feel 100% more comfortable with using natural sources of Calcium like bone to balance wholesome raw boneless meats.
Recreational Bones as a calcium source: Beef Knuckle Bones - Knuckle bones are hard, but not brittle. The animal will usually gnaw at the knuckle with its back molars wearing off small shavings at a time and nibble at cartilage with front teeth. Knuckle bones supply a good extra source of natural Calcium. In addition, they provide our pet’s great psychological pleasure, strengthen the neck and jaw muscles, and naturally keep their teeth and gums in good health.
Egg shells as a calcium source: Eggshells are approximately 95% Calcium Carbonate; the balance is mostly Magnesium, and Phosphorus. Eggshells also contain micro-elements, i.e., trace amounts of sodium, potassium, manganese, zinc, iron, copper and boron. The composition of an eggshell is quite similar to yours and your pet’s bones and teeth. Ground Eggshell contains about 1900 mg of Calcium per teaspoon. Further research indicates this 1 teaspoon of ground eggshell actually contains only 800mgs of elemental Calcium.
(Elemental Calcium meaning the amount actually absorbed).
The problem with egg shell is: There are concerns about adding ground eggshell to our dog’s and cat’s raw boneless meat meals because of the fact that Calcium Carbonate is essentially an antacid. The very high acidity in the carnivore’s gut is what allows them to eat and digest raw proteins without ill effects. If we add eggshell to raw meat are we not at the same time reducing the natural and essential acidity in our pet’s stomach? For this reason we would only use eggshell as a Calcium source when feeding that occasional cooked boneless meat meal or cooked eggs where the importance of extremely high levels of stomach acid is not as necessary to safely digest.
About Calcium Absorption: To function correctly Calcium requires Phosphorus (which is abundant in the boneless meats and present in bones as well). Experts also agree that Magnesium and Vitamin D, as well as Vitamin A and C should be consumed with
Calcium for best absorption. Unlike humans, dogs and cats synthesize Vitamin C internally. Magnesium is present in bones, eggshell, animal muscle meat, green leafy vegetables and chlorophyll, which is found highest in Chlorella. Vitamin A and Vitamin D are found in organ meat. Organ Meats supply a high level natural source of Vitamin D as well as Vitamin A, healthy amounts of Iron and all of the B Vitamins. Of course, the very best source of Vitamin D for you and your pets is the sun. Depending on the sun’s intensity, twenty minutes to an hour of sunshine each day will provide maximum benefit. This can be accomplished by taking your dog for a healthy walk and taking the time to sit outside with your pet or allowing them to do so.
All of these Calcium absorption enhancing vitamins are available as natural sources within a species-appropriate diet. They are better absorbed and safer than synthetic vitamins. Processed pet food has been recalled for excessive vitamin levels, one as recently as October 2010 involving excess quantities of Vitamin D. In addition, foods high in oxalic acid reduce Calcium uptake (e.g. spinach, beets, whole grains, and fiber-rich foods). Beet pulp, grains, and fiber fillers are some of the main ingredients in many processed pet foods.
Calcium Supplements: We believe whole real foods supply the most bio-available form of nutrients. Therefore, we do not give our dogs many supplements, but the need for Calcium to Phosphorus balance is important and if you are feeding boneless meats weekly, Calcium should be added to these meals. As an alternative to the more natural form of Calcium- ground bone or eggshell, some people use a Calcium supplement to increase the Calcium level in boneless meat meals.
We have already established that about 800 mg of elemental Calcium per one pound of raw boneless muscle meat (not considering organ meat) should bring the Calcium above the Phosphorus. Most supplements list the amount of elemental Calcium on the label, but you should verify with the manufacturer.
The biggest challenge with using supplements is identifying one that does not contain other ingredients that cause allergic reactions (such as itching, chewing, and ear issues) or ingredients that are not suitable for our companion animals.
Some examples: Many Calcium supplements also contain Vitamin D for its enhanced Calcium absorbency qualities. Dogs can take the Vitamin D3 – as Cholecalciferol which is
naturally occurring in the body. Cholecalciferol comes from the purified fat of lamb/sheep’s wool and is considered a pre-hormone. Once ingested it converts in the body in part to the hormone calcidiol and in part to a very potent anticancer steroid called Calcitriol.
Another form of Vitamin D is D2 (or Calciferol) as Ergocalciferol, which is a drug, not a vitamin. You want to avoid the D2 form of Vitamin D, Ergocalciferol. It is derived from plant fungus via a radiating process and is not detectable (naturally occurring) in the human body. Unlike humans, dogs and cats are not capable of converting Ergocalciferol (D2) into usable Vitamin D.
Stick with Calcium supplements that contain only the biologically active form of Vitamin D; the D3 as Cholecalciferol.
Calcium Citrate is said to be one of the most absorbable forms of the Calcium. The problem with Calcium Citrate is that it is made from Citric Acid which in most cases is derived from corn; posing an allergy issue for most pets.
Other ingredients - Corn and soy derivatives as well as MSG (an excitotoxin- disguised under various name) are added to many supplement products, including microcrystalline cellulous, Vitamin E as mixed tocopherols, lecithin, maltodextrin, and in some pet supplements (the powder, liquid, and chewable forms) carrageenan, natural flavors, and brewers yeast, etc.
Early on in the practice of raw feeding dogs and cats, experts recommended Bone Meal Calcium as the best supplement to use for balancing the Calcium to Phosphorus ratio boneless meats. Phosphorus is naturally found in Bone Meal as is Magnesium, Protein and many other minerals. Aluminum is a trace nutrient element that can be toxic at certain levels. Dr. Gloria Dodd, DVM has proven processed pet foods pose a great concern over aluminum toxicity. Aluminum is also administered each time our pets receive a vaccination. Heavy metals such as lead are a problem in our environment, especially in dust. Lead, once added to gasoline as an engine lubricant was emitted in automobile exhaust and today still contaminates American soil. Livestock do suffer lead toxicity; many cases are reportedly due to cattle accidentally ingesting discarded car battery parts or licking old crankcase oil. Lead is also unfortunately a reality; found in processed pet food (lead soldered cans), water (where lead soldered copper pipes exist), ceramic bowls, and invegetables grown in lead contaminated soil.
The good thing about Bone Meal compared to other Supplements is that it is pure Bone Meal, no other ingredients of concern. The best you can do if you choose to use Bone Meal, is select one that is sterilized and tested for heavy metals to assure the lowest possible aluminum and lead levels.
