The Essential Nutrients in Meat That Are Nearly Impossible to Get From Plants

If there’s one message I’ve been repeating for years, long before The Carnivore Code was published, it’s this: animal foods are the most nutrient-rich, bioavailable, and biologically congruent foods for humans. They’ve been at the center of human evolution for millions of years, and they continue to be the foundation of optimal human health today.

Yet, somewhere along the way, we became disconnected from this truth. We started fearing meat, fearing fat, and forgetting the biological brilliance of the nutrients found in animal foods, nutrients that plants simply cannot provide in the same form, if they provide them at all.

When I talk about the importance of meat, I’m not just talking about protein. Yes, protein quality matters, but that’s only the beginning. The real magic in meat lies in its unique suite of essential vitamins, minerals, peptides, and compounds that are either absent, poorly absorbed, or metabolically inferior when they come from plants.

This blog dives into the nutrients in meat, how effectively our bodies absorb them compared to plant-based nutrients, and what these differences mean for anyone focused on supporting their health.

1. Vitamin B12: The Irreplaceable Human Nutrient

Vitamin B12 is one of the clearest examples of a nutrient humans simply cannot get from plants. Period.

Why B12 Matters

• Required for methylation (affecting DNA, neurotransmitters, detox pathways)
• Essential for nerve myelin
• Prevents anemia
• Critical for fetal development
• Plays a role in cognitive function and mood

A deficiency in B12 isn’t subtle. It creates real and lasting damage. I’ve seen this firsthand in my medical practice, where people eating plant-heavy diets present with neurological issues that can take months or years to reverse.

Why Plants Can’t Provide It

Some people claim that fermented foods, algae, or “dirty” vegetables contain B12. But the forms found in plants are:

• B12 analogs (pseudovitamin B12)
• Biologically inactive
• Can block absorption of true B12

Only animal tissues, meat, eggs, milk, fish, organs can provide the real thing.

2. Heme Iron vs. Non-Heme Iron: It’s Not Even Close

Iron is essential for oxygen transport, immune function, and energy. But you’re not absorbing iron equally across foods.

Heme Iron (from animals):

• Absorption rate of ~15–35%
• Not inhibited by fiber, phytates, or oxalates

Non-Heme Iron (from plants):

• Absorption rate of ~2–5%
• Blocked by plant antinutrients
• Easily oxidized
• Often accompanied by inflammatory compounds

One of the most ironic things about plant-based messaging is that they constantly push spinach, lentils, and grains for iron, while ignoring the fact that your body may absorb almost none of it, especially in a plant-heavy diet where phytates are abundant.

There’s a reason those eating animal-based diets rarely have iron deficiency anemia.

3. Retinol (True Vitamin A) vs. Beta-Carotene

I’ve talked about this so many times: plants contain precursors to vitamin A, not the real thing.

Animal Foods Provide Retinol (Active Vitamin A)

Found only in:

• Liver
• Egg yolks
• Butter
• Dairy fat

Retinol requires no conversion and is immediately usable by the body

Plants Provide Beta-Carotene

Beta-carotene is:

• Poorly converted to retinol
• Highly variable (up to a 28-fold difference between individuals)
• Blocked by genetics, gut issues, illness, fat deficiencies
• Not efficient enough to meet human needs

A bowl of carrots is not the same thing as a tablespoon of liver.

4. Vitamin K2: The Missing Link in Bone and Heart Health

Vitamin K exists in multiple forms, but only animal-sourced K2 (MK-4) does what humans need most:

Directs calcium into bones Prevents calcification of arteries Supports insulin sensitivity Regulates sex hormones

Plants Only Provide K1 (Not Enough)

K1 from leafy greens:

• Has poor conversion to K2
• Doesn’t regulate calcium the way K2 does
• Requires bacteria that most people don’t have in abundance

Food sources of K2 come from animals:

• Beef
• Fatty meats
• Eggs
• Butter
• Cheese
• Liver

This is why people see bone density improvements, hormone stabilization, and better dental health when they reintroduce animal fats into their diets.

5. Creatine: The Missing Fuel for Brain and Muscle

Creatine is one of the most well-studied performance-enhancing nutrients on the planet and for good reason. Creatine:

• Improves strength
• Enhances energy production
• Supports cognitive function
• Protects brain health

Plants Have Zero Creatine

None.

If you don’t eat meat, you must supplement. And even then, it’s not the same as consuming it in the matrix of whole animal foods where creatine interacts with peptides, minerals, and amino acids naturally present in meat.

6. Taurine: Critical for the Heart, Brain & Immune System

Taurine is essential for:

• Heart rhythm regulation
• Bile acid production
• Antioxidant defenses
• Mitochondrial function
• Electrolyte balance

Humans synthesize some taurine, but nowhere near optimal levels.

Where does taurine come from?

Exclusively animal foods:

• Red meat
• Seafood
• Eggs

Plants contain none.

This matters. Taurine deficiencies are linked to heart issues, poor insulin sensitivity, and chronic fatigue.

7. DHA (not ALA): The Brain’s Required Fat

DHA is the structural fat of the human brain.

Animal foods supply DHA directly:

• Fatty fish
• Pasture-raised egg yolks
• Meat fats

Plants only supply ALA, which must be converted into DHA. That conversion rate is:

• <5% in healthy adults
• <1% in people with metabolic dysfunction
• Statistically zero in infants

If you rely on plants for omega-3s, you are almost certainly deficient in DHA.

8. Zinc & Copper Balance

Zinc is essential for:

• Immunity
• Hormone production
• Digestion
• DNA synthesis

Animal zinc is highly bioavailable. Plant zinc is not.

Why?

Plants contain:

• Phytates
• Lectins
• Oxalates

These bind minerals and prevent absorption.

Worse… plant-heavy diets often distort the zinc: copper ratio, which affects thyroid health and neurotransmitter balance.

9. Carnitine: Fat Metabolism Powerhouse

Carnitine shuttles fatty acids into mitochondria — literally enabling fat burning.

Animal foods are the only meaningful source:

• Red meat
• Lamb
• Dairy

Plants contain negligible amounts.

This is one reason many people feel exhausted or metabolically unstable on plant-based diets.

10. Bioavailable Protein (Complete Amino Acids)

Animal protein:

• Contains all essential amino acids
• Has optimal ratios for human use
• Is highly digestible (90%+)
• Supports muscle, bone, organ, and immune health

Plant protein:

• Lacks essential amino acids
• Is less digestible (50–70%)
• Comes packaged with antinutrients
• Often relies on fortification

This is why people eating animal-based diets see:

• Better body composition
• Faster recovery
• Improved cognitive function
• Stable hormones

The Big Picture: Meat Isn’t “Just Food” — It’s Human Fuel

Animal foods don’t just contain nutrients. They contain nutrients in the form, structure, and biochemical synergy that humans evolved to thrive on.

Plant foods, on the other hand:

• Provide incomplete forms
• Provide precursors that require inefficient conversion
• Provide minerals bound to antinutrients
• Provide compounds that irritate digestion
• Provide calories without the building blocks of optimal health

This is why, when people shift to an animal-based diet, they often describe it as life-changing. For the first time, they’re giving their bodies the exact nutrients they’re biologically designed for.

Organs: Nature’s Multivitamin

No discussion of nutrients from animals is complete without mentioning organs, especially liver, heart, spleen, thymus, and kidney.

They contain:

• Vitamin A
• B vitamins
• K2
• CoQ10
• Choline
• Heme iron
• Trace minerals
• Peptides like splenin and thymosin

These compounds don’t exist in meaningful amounts in plants, and they play a central role in immune function, metabolic stability, and hormonal balance.

Final Thoughts: Returning to the Foods We’re Designed for

Animal foods, especially meat and organs are not just nutrient-dense. They’re uniquely aligned with human physiology.

When we return to these foods:

• Energy improves
• Digestion stabilizes
• Mood lifts
• Hormones recalibrate
• Muscles grow
• Immunity strengthens

This isn’t magic. It’s biology.

And it’s why, after years of research, clinical practice, and personal experimentation, I continue to advocate for a return to the animal-based diet because it’s the most biologically consistent and nutritionally complete way to support human health.

*Questions or comments? Contact our team.