Ratio Diets vs Formulated Balanced Diets
There is a lot of debate about feeding dogs, not only in terms of commercial diets vs cooked vs raw diets but also whether to formulate a diet based on a ratio or a balanced, formulated diet. Everyone has the best interests of their dogs at heart and we all want to ensure our dogs are receiving all the nutrients they need to survive and thrive.
In this article I am going to discuss the difference between ratio diets and balancing over time versus feeding a nutritionally balanced, formulated recipe.
What is a ratio diet and what does balancing over time actually mean?
The concept of ratio diets became popular with the advancement of Dr. Billinghurts B.A.R.F diet, otherwise known as the Biologically Appropriate Raw Food diet. It refers to feeding a dog a ratio of meat, bones, organ meat and fruit/vegetables based on a percentage of their bodyweight.
Depending on who you talk to ratios vary. Some people follow the 7-1-1-1 model, which is 70% muscle meat, 10% raw bone, 10% fruit and vegetables and 10% organ meat (of which 5% should be liver). Other people like a 6-1-1-1-1 model, which is 60% muscle meat, 10% raw bone, 10% fruit and vegetables, 10% nuts and seeds and 10% organ meat (of which 5% should be liver).
Both ratios will work but it is important to note that they are only guidelines and you need to do what works for your dog as every dog is an individual. Some will do better with a bit more bone while others will do better with a bit more vegetables in their diet.
Anyone that follows this feeding approach acknowledges that the meals will not meet every nutrient requirement of their dog but believe that rotating meats, bones, organs and fruit and vegetables will address all their dog’s nutrient needs, balancing them over time. Balancing over time could be over a few days or weeks.
When feeding a ratio diet you first need to know your dog's bodyweight and then feed a percentage of their bodyweight (based on their energy/activity needs) as per the ratio you choose. The percentage used to calculate the amount of food to feed an adult dog is generally 2-6% of their body weight, depending on their activity level and age.
A guideline from Dr. B’s (Billinghurts) website for determining the percentage of bodyweight to feed an adult dog is:
Non-exercising healthy adult dogs or older dogs, feed 2-3% of bodyweight daily
Active healthy young adult dogs which exercise daily, feed 3-4% of bodyweight daily
Working, racing or high active dogs, feed approx. 3-6% of bodyweight daily. Feed the higher amount when active or working.
So let’s analyse a couple of examples of ratio diets
This is my dog Oscar and he weighs 15 Kg. He is a healthy, adult reasonably active 9 year old dog (notice his pearly white teeth).
For the purpose of this article I am choosing 3% of Oscar’s weight to determine how much daily food he should eat. Taking 3% of 15Kg gives us 450 grams to be fed daily, which I will divide into two meals so Oscar gets breakfast and dinner.
Applying the 7-1-1-1 ratio of 450 grams:
70% muscle meat (which can include heart and a mix of meats) is 315 grams
10% bone is 45 grams
10% fruit and vegetables is 45 grams
10% organ meat is 45 grams (5% should be liver)
Let’s make two meals using the above ratio guidelines and then we can look at the nutrients in each.
126 grams ground turkey, 126 grams ground beef and 63 grams lamb heart
45 grams bone, e.g. turkey neck (note: a small amount of meat is present on neck)
10 grams pumpkin, 10 grams blueberries, 10 grams spinach, 10 grams banana, 5 grams apple
22.5 grams beef liver, 22.5 grams beef kidney
At a glance this looks like a good recipe. Let’s analyse it to see what nutrients are met and what is deficient. (Note: anything less than 100% of nutrient requirements is highlighted in blue, if it meets nutrient requirements its green and if there is too much in the recipe its highlighted in red text)
(Nutrient profiles provided by Raw Fed and Nerdy Formulation spreadsheet)
Let’s step through the analysis of this recipe:
Calcium to phosphorus should be a ratio of 1.2 as a minimum. In this nutrient profile calcium is only 91% met however there is 167% of phosphorus in this recipe. That is only a ratio of 0.7. Minerals not only need to meet minimum requirements but they also need to be balanced. You may wonder why this is important. The reason is that some minerals bind to others and also compete with each other for absorption in the small intestine. Too much of one mineral means that other minerals will not be absorbed or at least only a small amount will be absorbed in the small intestine.
Vitamin E is only 2% in this recipe, not only do dogs have a minimum requirement of vitamin E (which is obviously not met in this recipe) but it also needs to be provided in higher quantities to offset the amount of fat in the diet. Higher levels of vitamin E are needed to stop oxidation of fats in the diet.
Only 28% of vitamin D is provided in this recipe, vitamin D is needed as it regulates calcium and phosphorus levels in the body, influences calcium and phosphorus absorption from the gastrointestinal tract and their deposition in bone tissue. A deficiency leads to impaired bone mineralisation and rickets in growing animals.
The protein content is excellent. All amino acid requirements are met.
Moving onto essential fatty acids (EFA’s) they also need to be meet minimum requirements (which they do in this recipe) but also need to meet a ratio too, anything from a ratio of 3:1 to 6:1 Omega 6:Omega 3. In the above example Linoleic acid is Omega 6 and Alpha-Linolenic Acid is Omega 3. So, although the minimum amounts are met in this recipe, the ratio of omega 6:3 in this recipe is way out of range, it is more than 10:1. Omega 6 are the inflammatory omega’s so this is a pro-inflammatory recipe.
In summary, feeding this recipe regularly would not be ideal as the ratio’s are not balanced, some nutrients are too high and some are too low.
200 grams ground chicken, 115 grams tinned sardines (in springwater)
45 grams bone, e.g. chicken feet with skin
20 grams pumpkin, 5 grams papaya, 20 grams broccoli
22.5 grams lamb liver, 22.5 grams pancreas
The analysis of this recipe gives us the following results:
(Nutrient profiles provided by Raw Fed and Nerdy Formulation spreadsheet)
Analysing the nutrient profile of this recipe we see:
This recipe also meets all protein (amino acid) requirements.
Omega 3 and Omega 6 requirements are met
Most of the B vitamin requirements are met except for Thiamin (B1). A deficiency of Thiamin can significantly affect the functioning of the Central Nervous System (CNS).
Vitamin E is also not met as only 8% of the requirements are provided in this diet.
Calcium doesn’t meet minimum requirements and doesn’t meet the calcium to phosphorus ratio
Amount of zinc in the diet is also too low and doesn’t meet the zinc to copper ratio
Magnesium and manganese also don’t meet minimum requirements. Manganese is necessary for normal bone development and reproduction. Magnesium is required for protein and carbohydrate metabolism, as well as providing structure to the skeleton. Magnesium is a mineral that should not be consumed in excess as it is linked to the formation of struvite urolithiasis (bladder stones).
Vitamin D is well supplied in this recipe which does balance out the deficiency of vitamin D in the previous recipe
As you can see from these two recipes, although they meet the requirements of a ratio diet they do not provide all the nutrients a dog meets. If these two recipes were rotated there would be a consistent lack of nutrients in the diet and unbalanced minerals. Over time these nutrients will not be balanced and this will lead to ill health due to nutrient deficiencies. Finally, as B vitamins are water soluble they need to be met in the diet every day. Also, there is a low capacity in the body so store zinc, so it is also recommended to provide this mineral every day too.
A formulated, balanced diet
In contrast, a formulated balanced diet are homemade recipes that meet the recommended amount of nutrients as defined by either the NRC, AAFCO or FEDIAF. The nutrients in the recipes are also balanced to ensure that the correct ratio of minerals are supplied in the meal, e.g. calcium to phosphorus, zinc to copper. By feeding a balanced meal every time it takes the guess work out of trying to balance over time using a ratio diet and also eliminates the risk of long term nutrient deficiencies or feeding above the safe upper limit which can eventually lead to toxic levels in the body.
In summary, when choosing to formulate a homebased ratio diet for your dog its important to know what nutrients the recipe is deficient in to ensure they are met in another recipe. Ratio diets require a lot of guesswork as you don't know what nutrients are missing and which are being fed in excess. Balanced recipes, just like buying a pre-prepared meal off the shelf for your pet, give peace of mind that your pet is receiving all the nutrients it needs in the required amounts to survive and thrive.