Calcium and Phosphorus in Raw Feeding
Katherine AllenShare
What They Actually Do — and Why Balance Matters
Before we talk about ratios, let’s talk about function.
Because if you don’t understand what calcium and phosphorus actually do in the body, the numbers mean nothing.
What Calcium Really Does
Most people think:
Calcium = bones.
That’s part of it.
But calcium is also responsible for:
• Muscle contraction
• Nerve transmission
• Blood clotting
• Hormone release
• Heart rhythm regulation
The body regulates blood calcium very tightly. If dietary intake is off, the body will pull calcium from bone to maintain balance.
That’s not a short-term problem.
But during growth, it can become one.
What Phosphorus Does
Phosphorus doesn’t get talked about as much — but it should.
It plays a role in:
• Bone formation
• Energy production (ATP)
• Cell membrane structure
• DNA and RNA function
Muscle meat is naturally rich in phosphorus.
That’s important.
Because when you feed mostly muscle meat without proper bone balance, phosphorus intake rises — and calcium must keep up.
Why They Must Work Together
Calcium and phosphorus are partners.
Too much phosphorus without enough calcium?
The body pulls calcium from bone.
Too much calcium without enough phosphorus?
Mineral imbalance.
The body constantly adjusts to maintain equilibrium.
During adulthood, it has flexibility.
During rapid growth, that flexibility narrows.
Now Let’s Talk Ratio
For growing puppies, the generally accepted calcium-to-phosphorus ratio lands around:
1.2 : 1 to 1.4 : 1
That doesn’t mean you need a chemistry lab.
It means structure matters.
How Raw Feeding Controls It
Muscle meat → higher in phosphorus
Bone → provides calcium and phosphorus in appropriate proportions
When feeding a structured raw framework like:
• ~80% muscle meat
• ~15% raw meaty bone
• ~5% liver
• ~5% other secreting organ
You are indirectly managing that ratio.
Consistency controls balance.
Not guesswork.
Why Eggshell Alone Isn’t Equivalent
Eggshell is calcium.
It does not contain phosphorus.
Adding eggshell to boneless meat increases calcium without addressing phosphorus intake.
For certain adult scenarios, that may work.
For growing puppies, relying on eggshell alone can distort balance if phosphorus isn’t properly accounted for.
Why Puppies Are Less Forgiving
Puppies are building:
• Long bones
• Growth plates
• Joint alignment
• Connective tissue
Mineral imbalance during this phase doesn’t always show immediately.
But growth amplifies mistakes.
That’s why structure is protective.
The Bigger Picture
Calcium and phosphorus aren’t scary.
They’re foundational.
You don’t need to obsess over decimal points.
You need:
• Controlled bone percentage
• Awareness of what contributes phosphorus
• Consistency during growth
Feed with structure.
Feed with intention.
The ratio takes care of itself when the framework is solid.