Hannah Zulueta Formulation · Owner Questions
Why One Swap Changes the Whole Sheet
A client asked me why swapping one ingredient rewrote her whole recipe. Here is the answer.
A client wrote to me this week with a question that deserved more than a paragraph back.
She had asked for a change to her dog’s recipe. I made it, and the updated version came back with adjustments running through half the ingredient list. She wanted to know why one substitution had produced so many others. She also said something I hear often: she was buying a lot of products, and she would like to keep this simpler than it was becoming.
That is a fair question and she was right to ask it. I answered her directly, and then I sat with it, because I would guess she is not the only person wondering.
Almost everything on this website started the same way. Someone asks me something in a consultation or an email, I answer it, and then I realize the answer belongs somewhere other than one person’s inbox. If you have been reading here for a while, you have been reading other owners’ questions.
So here is that one, at full length.
The one thing to know
A recipe is not a list of ingredients sitting next to each other. It is a set of ratios.
Move one thing and the ratios have to be solved again.
Definitions
What an ingredient actually is
The word ingredient makes it sound like each item does one job. Chicken is the protein. Sweet potato is the carbohydrate. Oil is the fat.
That is not how any of it works. Every ingredient carries dozens of nutrients at once, in amounts that have nothing to do with what we mentally file it under.
Chicken is filed under protein. It is also a large share of the fat in most recipes, which means a large share of the calories, and calories drive everything else.
Liver is filed under organ meat. It is also the copper, most of the vitamin A, a good part of the B12 and the iron.
Spleen is filed under organ meat too, and people assume it behaves like liver. It does not. Spleen is in a recipe for iron.
So when we swap one protein for another, we are not moving a protein. We are moving fat, calories, zinc, iron, several B vitamins, and in Chinese medicine terms, the temperature of the whole meal.
The mechanism
Calories are the denominator
Nutrient requirements for dogs are not expressed as a flat amount per day. They are expressed per unit of energy, per 1000 kilocalories. A dog eating more calories needs proportionally more of everything else, and the targets are written that way.
Which means calories are not one line on the sheet. Calories sit underneath every other line.
Change an ingredient and the calorie total shifts. The moment it shifts, every nutrient value is being divided by a different number than it was five minutes ago. Some that were comfortably in range fall below it. Others that were fine climb toward a ceiling. Nothing about those nutrients changed. The energy they are measured against did.
That is why one substitution does not stay put. It is not fussiness on my end. It is arithmetic.
Worked example one
Ground turkey and chicken breast
Both poultry, both sitting a foot apart in the same case, and the swap people are most likely to make on their own without asking me, because it looks like nothing.
Here is what actually sits inside each one. Ground turkey at 93 percent lean, raw, against raw chicken breast with no skin.
Start with the calories. Turkey carries 1498.6 kcal per kilogram against chicken breast at 1144.6. That is thirty percent more energy for the same weight of food, and the moment that number moves, every other line is being divided by something different.
The fat explains it. 8.34 percent against 2.5 percent. More than three times as much.
The fat is not only calories. Linoleic acid runs 2.23 grams in the turkey against 0.347 in the chicken breast, six times the amount. That is an essential fatty acid with a minimum requirement, and it is the single widest gap on this sheet.
Zinc nearly quadruples. 2.53 against 0.728. In any dog with skin involvement, zinc is a number I am already watching, and this swap moves it more than most supplements would.
Now here is the part that makes this hard.
Several values move the opposite way. Chicken breast carries more protein, nearly double the niacin, almost twice the B6, more choline, more potassium, and more phosphorus. It also shows taurine at 15.9 milligrams where the turkey entry shows none.
So the swap does not make the recipe richer or leaner. It moves roughly a dozen values in two directions at once. Some rise past where I wanted them. Others fall under a minimum. Restoring all of it takes changes to several other ingredients, which is the long email you received.
A note on the zeros. A few entries read as zero when the honest answer is that nobody measured them. Taurine and purines in the turkey entry are almost certainly that rather than a true absence. I mention it because it is another reason substitutions do not get eyeballed. Even the database has holes in it, and knowing where they are is part of the work.
And the swap moves the temperature
Chicken is warming. Turkey sits cooler, closer to neutral. That is not a side note in how I formulate.
For a hot, itchy, red-skinned dog, moving toward turkey is a therapeutic change and I might make it deliberately. For a cold, thin, older dog with weak digestion, it is the wrong direction and it can undo work we spent months on. I wrote about where turkey sits in is turkey cooling or warming, and the full list is in the TCM food energy list.
One swap that looked like nothing. It moved the calories, the essential fats, a dozen micronutrients in two directions, and the thermal direction of the whole recipe.
Worked example two
The same problem, with higher stakes
Poultry is the swap people make casually. Vegetables are the one people do not even think of as a swap. Green beans, broccoli, both green, both vegetables, both things a dog can eat.
Here they are side by side, raw, per 100 grams.
The fiber is identical, which is the only thing on this list people usually think about when choosing a vegetable.
Everything else is not close. Broccoli carries almost four times the calories, nearly double the phosphorus, and about forty percent more potassium.
Now, here is the part I want to be clear about, because it cuts both ways.
If your dog is healthy, none of this reaches them. A sound pair of kidneys handles the extra phosphorus and the extra potassium without any help from me, and you can put green beans or broccoli in the bowl on the basis of what they like and what is in the fridge. I am not asking anybody to weigh vegetables for a well dog.
Kidney disease removes that margin. Phosphorus and potassium stop being background numbers and become the two things being actively managed, and a dog can be in trouble on both at once. That is the dog this next part is written for.
Kidney disease
What this means for a CKD dog
Potassium in kidney disease is not a single target. It moves in either direction depending on the dog and the stage, and the two directions call for opposite food.
Tap the situation that matches your dog’s labs.
Hyperkalemia
This shows up in later-stage disease, when urine output falls, and in dogs on certain blood pressure medications. It is a cardiac concern and your vet is the one managing it.
Food is not the lever that fixes it. Food should also not be fighting it. In that dog, green beans at 209 milligrams sit better than broccoli at 300.
Hypokalemia
This is common in kidney disease too, from the volume of urine produced, from poor intake, from vomiting, from diuretics.
Here the dog needs more potassium in the bowl, and broccoli at 300 is doing something green beans cannot.
So far this looks simple. Read the potassium, pick the vegetable.
Here is the part that is not simple
Phosphorus is the number that drives kidney disease progression, and broccoli carries 68 milligrams against 38 in green beans. Nearly double.
Which means the low-potassium dog has a problem. The vegetable that solves the potassium is the same vegetable that worsens the phosphorus. You cannot fix both with one swap, and the answer is not sitting in the vegetable drawer. It comes from moving several other things in the recipe to make room for the one change you actually need.
A healthy dog absorbs all of this without anyone noticing. A dog carrying a phosphorus problem and a potassium problem at the same time has no room to absorb anything, and every swap has to be made on purpose.
One more crosscurrent. Broccoli carries almost four times the calories. In a kidney dog who is not eating well, that energy density is useful rather than a drawback, and I might want it for exactly that reason while working around what it brings with it.
Three considerations, pulling three directions, from one vegetable.
Ceilings
Which is also why limits exist
The same logic runs in the other direction, and this is where owners are often right to be nervous.
Copper is the clearest example. Dogs need copper. Copper is also the nutrient I watch most carefully in any dog with liver values that have been climbing, because liver is a spectacular copper source and it is easy to overshoot without noticing.
So I hold liver to a ceiling in every recipe I write. Not because liver is bad. Because the amount is what determines whether it helps or hurts, and somebody has to be responsible for knowing where that line sits.
The same is true of zinc, of vitamin D, of iodine. None of them are dangerous ingredients. All of them have an amount past which they stop being useful.
When an owner asks me whether adding an organ will overload the copper, that is the right question asked for the right reason. In the case that prompted this article the answer was no, because the organ in question contributes iron rather than copper. But I would rather be asked a hundred times than have someone quietly add an extra spoonful of liver because it seemed healthy.
The real complaint
About the shopping list
Here is the part I want to say plainly, because it is what sits underneath the question.
The list is long at the start. It gets shorter.
The beginning of a case is the building phase. We are correcting deficiencies, moving several numbers at once, and often working around what a dog will actually eat while feeling unwell. That takes more ingredients than the same dog will need six months later.
Once things stabilize, the recipe simplifies. Ingredients that were doing corrective work come out. Rotations get wider, which means you are not hunting one specific item.
If a product is hard to source, tell me. That is useful information and I can usually formulate around it. What does not work is quietly substituting something similar, because the whole page recalculates and neither of us knows what it recalculated to.
Standard
Why I hold it this tightly
Your vet counts every milligram of your dog’s medication. You read every decimal on their labs, and you should.
I hold the food to that same standard.
Food is not replacing the medical plan. It is supporting it, and it can only support it if the numbers are actually right. A recipe that is close enough is a recipe doing something other than what it says on the label.
That is the whole reason a small change produces a long email from me. Not because the change was a problem. Because checking what it did is the job.
What to do
What this means for you
Fair warning
How I work, and whether that suits you
I should be upfront about something.
I am the type to niggle over these details. If you work with me, you are going to get emails about linoleic acid and phosphorus decimals, and a recipe update that changed six lines when you asked to change one.
Some people find that reassuring. Some people find it exhausting, and I would rather you know before we start than three weeks in. If you want someone who will tell you that beef and chicken are basically the same and to stop worrying, that person exists and there is no shame in wanting them. This is not everyone’s preference, and that is completely fine.
Here is why I am like this.
I watch what I eat. Not out of vanity, and not in a way that runs my life, but because the details do real work in a body. That becomes more true with age, not less. Midlife and the years after are exactly when the small things start showing up in how you feel, how you sleep, what your bloodwork says, and how well you recover from anything at all.
I do not hold your dog to a standard I would not hold myself to. I formulate for my own three the same way I formulate for yours, and I read a recipe you send me with the same attention I would give my own bloodwork.
Your dog will be at this for years. The small numbers are what add up over years.
How we find out
The truth reveals itself
A recipe is the best answer I can give with what I know on the day I write it. It is built out of numbers, and those numbers describe the food. They do not describe your dog.
Then you feed it, and they start answering.
They answer in their coat, in their stool, in whether they come to the bowl. They answer in how they get off the couch in the morning. If you run labs, they answer there too, in whether the values move the direction we were aiming for or sit exactly where they were.
That is the part no spreadsheet reaches. I can tell you what should happen. Your dog tells us what did.
Which is why I ask for the follow-up. Your dog is the only one who knows whether the food is being metabolized the way we intended, and they will say so plainly if anyone is watching.
Build it carefully, feed it, and then pay attention. Your dog tells you what is best.
Read next
Complete and balanced: AAFCO, NRC and FEDIAF
Warming and cooling foods: the TCM food energy list
Nutrient values from Animal Diet Formulator, using USDA and ADF Typicals entries as noted in each table. Values are for raw ingredients per 100 grams unless stated otherwise. The information on Daily Dog Food Recipes is intended for nutritional, informational and educational purposes only. Please consult your veterinarian about your dog’s medical care.
Hannah Zulueta obtained her Certificate in Canine Nutrition from CASI Institute. She is also studying for her Doctorate in Acupuncture, Traditional Chinese Medicine, and Herbalism from the esteemed Pacific College of Health and Medicine. If you’re as keenly interested in health for yourself, visit her website for human health: Satori Acupuncture and Herbs.
She resides in San Diego with her three dogs, Maggie, Orbit, and Mr. Higgins.
She is available for one on one consultations. She develops evidence-based recipes that meet both NRC and AAFCO nutritional standards while integrating the therapeutic food principles of Traditional Chinese Veterinary Medicine into her formulations.
Additionally, you can find her sharing free content on Instagram.
