Role of Animal Fat in Human Health

🧈 Why Animal Fat Is Essential for Human Health.

In this article I am going to explore the role of animal fat in Human Health. It has been demonized for ages, but wrongly so. Evidence suggests that the low-fat movement in the 70s was sponsored by the sugar industry to promote processed foods. This has resulted in the obesity epidemic, as people swapped healthy eggs and meat for processed cereals and carbohydrates. [read more here] Evidence shows that those who consume low-fat dairy products (which are more processed and less natural) tend to be fatter. [LOW FAT DAIRY MAKES YOU FAT - article here]

🧠 1. The Brain: Built on Fat

Your brain is nearly 60% fat by dry weight, and most of that is saturated and monounsaturated fat — the kind found in meat, butter, eggs. The reason our brain has evolved is due to availability of fatty meat, organs, bone marrow and brain!

• Myelin, the insulating layer that allows neurons to fire efficiently, is rich in saturated fat and cholesterol.
• Cholesterol is not just safe for the brain — it’s essential. It keeps neurons stable, supports memory, and acts as a building block for neurotransmitters and hormones.
• Omega-3 fats (DHA and EPA) from fatty fish improve communication between brain cells and help protect against depression and cognitive decline.

And when we eat fewer carbs, our brains start using ketones (from fat) as fuel — which enhance mental clarity, protect neurons, and reduce inflammation. That’s one reason why many people report sharper thinking on a higher-fat, lower-carb diet.

PS- see my article on what statins do to your brain.

❤️ 2. The Heart: Runs on Fat

It may surprise you, but the heart’s preferred fuel is fat, not sugar. The country in Europe with highest saturated fat consumption is France - which has the LOWEST risk of heart disease. 2ND highest fat consumption? Switzerland. 2nd lowest. Breast milk is rich in saturated fat, yet babies do not die of heart disease.

About 70% of is energy comes from fatty acid oxidation.

• Saturated fats (like stearic acid in beef and butter) provide steady, clean energy for heart muscle without spiking blood sugar. They also produce less inflammation when burned as fuel compared to Polyunsaturated Fat.
• When in ketosis, the heart can also burn ketones very efficiently — producing more energy with less oxidative stress.
• Contrary to old beliefs, natural saturated fats do not clog arteries. They actually help form stable, non-oxidized cell membranes, which resist damage and inflammation.

Meanwhile, animal sources of omega-3s (EPA/DHA) improve blood vessel function and reduce inflammation inside artery walls. BLOOD OMEGA3 level can be used as a direct predictor of heart disease. If you eat too many nuts, grains, seeds and refined oils, the omega 3:6 ratio in your blood will be disrupted, increasing risk of heart disease. See graph below:

🦠 3. The Immune System: Fat as a Signal and Shield

Our immune cells are wrapped in membranes made of fat. The balance between saturated, monounsaturated, and polyunsaturated fats determines how well those cells respond to threats.

• Animal fats provide cholesterol and sphingolipids, which form “lipid rafts” — tiny platforms that help immune cells communicate and respond quickly to infections.
• Arachidonic acid, found in meat and eggs, acts as a raw material for immune signalling molecules (prostaglandins, leukotrienes).
• In balance, these signals keep inflammation under control. When we replace natural fats with unstable seed oils, that balance tips toward chronic inflammation - ALL DISEASES ARE CAUSED BY CHRONIC INFLAMMATION.

🧬 4. Hormones and Reproduction: Cholesterol as the Master Molecule

Every steroid hormone in your body — oestrogen, progesterone, testosterone, cortisol — starts from cholesterol. Without enough dietary fat, your endocrine system simply can’t function properly.

• Fat and cholesterol enable the production of sex hormones, supporting fertility, libido, and menstrual regularity.
• Adequate fat intake improves thyroid hormone conversion (T4 → T3), supporting energy and metabolism.
• Fats also help maintain insulin sensitivity, especially those from grass-fed animals rich in stearic and oleic acid. Fat is the only macronutrient that does not trigger insulin release, and it also stimulates GLP-1, simulating OZEMPIC.

Low-fat diets, by contrast, often lead to fatigue, hormonal imbalance, and menstrual irregularities — signs that your body is conserving energy due to a perceived shortage of building blocks.

💪 5. Muscles, Bones, and Joints: Fat for Strength and Flexibility

Animal fats carry several fat-soluble vitamins critical for tissue repair and resilience:

• Vitamin D3 (from fatty fish, eggs, liver) helps your body absorb calcium and supports bone mineralization.
• Vitamin K2 (abundant in grass-fed butter and cheese) directs calcium into bones and teeth and away from arteries.
• Vitamin A (retinol) supports collagen formation, immune function, and reproduction.
• Vitamin E acts as an antioxidant, protecting fatty tissues from oxidative stress.

These nutrients work together — they’re absorbed and transported only in the presence of dietary fat. Without fat, these vitamins can’t do their job. PLEASE NOTE that these vitamins are only found in animal fat, not plants.

🧫 6. Gut and Digestion: Fat as a Metabolic Regulator, Satiety, diabetes & fatty liver

When you eat fat, your body releases bile, which not only helps digest fats but also stimulates gut motility and prevents gallstones.

• Animal fats encourage a healthy bile flow and nourish the intestinal lining.
• Certain fatty acids help maintain tight junctions in the gut, preventing “leaky gut” and systemic inflammation.
• Fats also shape your gut microbiome, promoting species that reduce inflammation and support metabolism.
• Eating fat promotes satiety by stimulating the GLP-1 receptor, This is similar to how OZEMPIC works. If you eat a high-fat low-carb diet it acts exactly like OZEMPIC. [see my LinkedIn article here - KETO MIMICS OZEMPIC]
• Since fat is satiating, you generally eat less if you eat more animal fat - as shown as study above. This means you will be less likely to eat a lot or binge eat on carbs. This means you will have lower risk of obesity and diabetes.
• Reduced risk of fatty liver: eating fat INHIBITS fat synthesis in the liver. Eating carbs or even protein in excess causes insulin surge which causes fatty liver. 

🧍‍♀️ 7. Skin and Hair: Beauty from Within

• The outer layer of your skin, the stratum corneum, is built from ceramides and cholesterol, both derived from saturated fat.
• They form a waterproof barrier that keeps your skin supple and hydrated.
• Low-fat diets — or diets high in seed oils — can lead to dry, inflamed skin, brittle hair, and impaired wound healing.

⚙️ 8. Mitochondria: Fat and Ketones as Clean Energy

Inside every cell, the mitochondria are the power plants that keep us alive.

Fats are their favourite fuel source — producing more ATP per molecule and less oxidative stress compared to glucose.

Ketones, derived from fat, also:

• Increase NAD⁺, enhancing cellular repair.
• Activate sirtuins (longevity enzymes).
• Protect mitochondria from damage and aging.

🌿 Final Thoughts

- Avoid taking a statin - it will damage every cell in your body.

- Avoid phytosterols especially if you are on a statin. Eat animal fats instead - See this video on the dangers of phytosterol. You are an animal, not a plant, so your body needs cholesterol not phytosterol.

- Cook with saturated fats such as ghee, coconut oil and tallow.

- Cold pressed oils can be used for salad dressings. Avoid heating PUFAs - especially fatty fish - lightly heat. 

- Avoid vegetable oils at all cost. This includes margarines, rapeseed oil, sunflower, safflower, rice bran, corn oil, soy, grapeseed oil cottonseed oil. ENSURE you avoid any foods from outside that are deep fried in vegetable oils. See my article on seed oils here.

- Avoid fried foods and excessive heating of foods.