The Proper Human Diet or “PHD” is an approach to low-carb eating developed by ketocarnivore enthusiast Dr. Ken Berry. The Proper Human Diet calls for centering meals around high-quality meats and animal fats, eliminating all grains, sugars, seed oils, and processed foods while allowing very limited amounts (if any and all) of low-carb veggies and fruits. Dr. Berry developed the Proper Human Diet based on years of personal experimentation, his family medicine practice observations, and anthropological research on ancestral eating patterns.

What is the Proper Human Diet?

The PHD is a type of low-carb high-fat ketogenic eating plan that prizes meat and animal fats. This way of eating eliminates all processed foods and minimizes fruits and vegetables. It avoids all inflammatory foods and those which may contain toxins and antinutrients. The PHD is proposed as a way of realigning your physiology with ancestral eating habits.

The PHD founder Dr. Ken Berry points out that dietary guidelines are misleading and downright dangerous. Foods that we’ve been told to eat are inflammatory and toxic, while wholesome, nutrient-dense animal foods, especially red meat, eggs, and saturated animal fats, have been demonized with bad science and propaganda. Thankfully modern science is setting the record straight. [1] [2] [3] [4] [5] [6]

Dr. Berry’s message: Do not trust industrial food producers and the organizations they support (like the American Heart Association) to have your health in their best interest. If you want to get healthy, eat like our ancestors.

This approach is based on a growing body of research showing that our paleolithic ancestors were hyper-carnivorous apex predators that thrived on fatty meat from large animals for nearly two million years. [7]

It wasn’t until humans essentially ate these large animals into extinction that we began cultivating plants around 10,000 years ago. [8]

The legacy of our fatty-meat-seeking ancestral evolution persists in the physiology of modern humans. In short, our bodies are designed to thrive on meat and animal fat. Furthermore, fruits and veggies served only small and temporary roles in the ancestral diet. As a food of last resort, they are not essential and can contain harmful plant toxins and antinutrients.

Grains, sugars, and industrial seed “vegetable” oils were nonexistent and have been shown to be highly inflammatory.

“Proper” then refers to a diet that is most properly aligned with human physiological needs and therefore provides the body with exactly the nutrients we need while eliminating all harmful foods.

Dr. Ken Berry

Dr. Ken Berry

Dr. Berry developed the Proper Human Diet during his career as a family doctor. After more than a decade of treating over 25,000 patients, Dr. Berry proclaimed, “I’ve seen so much suffering and heartache, all because of the unnecessary complications of diseases caused by our modern diet. Well, I’ve had enough!”

Dr. Berry gained widespread recognition with his bestselling book “Lies My Doctor Told Me” and has since gained over 2.5 million ardent YouTube followers.

Dr. Berry now makes it his mission to promote the Proper Human Diet as a powerful lifestyle approach to treating the diseases he sees in his office every day, including metabolic syndrome, Type-2 diabetes, obesity, fatty liver, heart disease, and depression.

Dr. Berry and his wife Nisha (who suffers from Hashimoto’s) experimented with different versions of keto for years. And in 2020, Dr. Berry made the transition to the all-meat carnivore diet.

The carnivore diet can be seen as a somewhat more restrictive version of his Proper Human Diet.

Foods To Eat on the Proper Human Diet

If it used to moo, bleat, oink, swim, or cluck (and whatever sound bivalves make), then you should eat it! Additionally, eggs and cheese are excellent PHD foods. Some fruits, greens, and low-carb veggies are permitted in a supplementary role. Here is a list of Proper Human Diet Foods listed in order of importance.

Ruminant Meat
The best, most nutrient-dense meats with the healthiest fat profiles are from ruminant animals:

  • Beef: Ribeye steak is the meat of choice for most Proper Human dieters. At the same time, less expensive meats like 70/30 ground beef are an excellent budget option.
  • Lamb
  • Goat
  • Bison
  • Buffalo
  • Deer
  • Moose

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2. Pork
Pork products like ribs, pork belly, and bacon are also excellent, though they are considered second-tier because they are less nutrient-dense and have a good but less-optimal array of fatty acids when compared to ruminant meats.

3. Animal Fats
The Proper Human Diet eliminates most carbs, which means you have to get most of your calories (70-80%) from fat.
If you eat too much protein (more than 1 gram of protein per 1 gram of fat), you’ll get protein poisoning.
So, choose fatty cuts of meat and add generous helpings of animal fats like:

  • Butter
  • Ghee
  • Lard
  • Beef, bison, and duck tallow

Some people practicing the Proper Human Diet also allow for coconut and olive oil. Be sure to dispose of all other vegetable oils and shortening. These Industrial oils are toxic, inflammatory, and maybe the most dangerous dietary substance out there. [9]
In fact, studies show that the only lifestyle factors more deadly than consuming vegetable oil are severe obesity and heavy smoking. When considering that vegetable oil is implicated in obesity, it may be more accurate to label vegetable oils as public enemy number one.

Common vegetable oils to avoid include:

4. Eggs
Eggs are perhaps the most nutritionally complete food on earth. This makes sense when considering that they need to contain all the building blocks for growing an entire creature. Their combination of healthy fats, complete high-quality proteins, and an abundance of vitamin D and vitamin K make eggs a supremely proper food for the human diet.

5. Fatty Cheese
Some Proper Human Dieters choose to eliminate all dairy for 30-90 days to assess for dairy allergies. At the same time, others make fatty ripened cheeses a PHD staple. Fatty cheeses can be a great way to maintain the pleasure of variety while boosting your intake of healthy fatty acids and fat-soluble vitamins. Ripened cheeses like pecorino and blue cheese offer the added benefit of tens of thousands bioactive compounds that promote heart health and that have even been shown to reverse aging. [4] [5]

6. Organ Meats
Organ meats, widely considered nature’s most potent multi-vitamin, pack a nearly unbelievable amount of vital nutrients, including B vitamins and vitamins A, E, K2, D, and C. Bone broth, especially when made at home from marrow bones, provides collagen and complex amino acids that help repair the intestinal lining and support joint and skin health.

7. Seafood
Fatty fish like Salmon provide high-quality protein, healthy fats, including omega-3s, and a complex of B vitamins. While shellfish like mussels and oysters provide crucial vitamins and minerals, including robust amounts of vitamins B and D, zinc, selenium, and copper. Beware that most seafood is contaminated with toxins from industrial pollution. For this reason, seafood is optimally enjoyed once in a while on the Proper Human Diet.

8. Salt and Electrolytes
Though not technically a food, salt, and electrolytes are important dietary nutrients and become even more important on low-carb eating plans like the Proper Human Diet. This is because when you cut carbs, your body flushes water weight and along with it, electrolytes like glycogen and magnesium. This flushing is often a temporary side effect of the transition from a high-carb diet. Liberally salting your foods is key to maintaining your electrolyte levels. Doctors knowledgeable about low-carb diets generally recommend increasing salt consumption to 12 grams (2 teaspoons) of salt per day in the first few days of adapting. After that, it is generally recommended that you consume 5 grams (1 teaspoon) of salt daily to avoid flu-like symptoms of headaches, fatigue, and constipation. [10]

Here’s a list of low-carb-friendly veggies:
9. Vegetables
Though Dr. Berry himself avoids all plant foods, he views most vegetables as fine on a PHD when consumed in moderation. His rule of thumb: “If it’s green and leafy then go for it! If it’s starchy or sweet, then avoid it.”
10. Fruit
Most fruits are too high in carbs to be enjoyed often on a Proper Human Diet. Dr. Berry points out that in the context of human dietary evolution, fruits were seasonal. When we eat fruit (and all sugar), our body sends signals telling us to eat more as fast as possible. This causes a spike in the hormone insulin, which tells the body to turn excess sugar into fat that is stored on our bodies to be used as an emergency fuel source when food is scarcer in the winter.

However, for modern humans, food is rarely scarce, and once you start eating sugar, this loop is self-reinforcing and hard to escape (meaning the more fruit/sugar you eat, the more you want). So, if you’re seeking to reduce sugar intake, loose excess weight, and reduce inflammation, cutting out most fruit is a wise move. And remember that drinking freshly squeezed juice often has more sugar than a soda. If you’re trying to lose weight, reducing sugar intake is key.

This list of lower-carb fruits can be consumed in moderation:

11. Nuts and Seeds

Nuts and seeds are generally low in carbs and high in fat. However, they’re also high in abrasive fiber, inflammatory Omega-6 fatty acids, and often contain plant toxins and antinutrients that minimize their overall health benefits.

For this reason, nuts and seeds in the Proper Human Diet should be consumed only occasionally.

A list of acceptable nuts and seeds includes:

Nut Carbohydrate per 100g Amount of Nuts per 100g
Nut Carbohydrate per 100g Amount of Nuts per 100g
Pecan 4 Grams 20 nuts
Brazil 5 Grams 40 nuts
Macadamia 7 Grams 70 nuts
Hazelnut 7 Grams 50 halves
Walnut 9 Grams 80 nuts
Almond 9 Grams 5/8 cup
Hemp Hearts 28 Grams 160 nuts


If our ancient ancestors didn’t drink it, it’s probably better that we don’t either. This leaves us with mineral water. If you do rely on caffeinated beverages, choose low-carb coffee and tea made without sugar. But feel free to add butter. Alcohol like gin, vodka, and whisky are simply not good for us, so they are best avoided. Diet sodas, though low in real sugar, often contain artificial ingredients that are certainly not ancestrally aligned. Carbonated mineral water is fine if you can’t go without your bubbles.


Sugar in every form and other “natural” sweeteners like honey and maple syrup are eliminated on the Proper Human Diet. When you’re focusing on single-ingredient whole foods, there’s rarely an opportunity for them anyway. If you are not concerned about weight loss and you get into more creative low-carb keto-friendly recipes, Stevia, Monk Fruit Extract, and Allulose are all acceptable in moderation.

Health Benefits of the Proper Human Diet

The Proper Human Diet is essentially a more ancestrally aligned version of a ketogenic diet. Very low-carb, high-fat ketogenic diets have been subject to hundreds of clinical studies which show them to provide powerful health benefits. Some of the benefits of the Proper Human Diet may include:

  1. Promotes weight loss while sparing muscle mass. You’ll look and feel better while reducing dangerous visceral fat and improving your quality of life.
  2. Reduces food cravings: high-fat, moderate-protein, and low-carb eating help increase feelings of fullness and reduce hormones like leptin and insulin that directly drive food cravings.
  3. Increased insulin sensitivity: Reducing carbs stabilizes blood glucose and insulin levels, making it a powerful intervention for people with metabolic syndrome, type 2 diabetes, and insulin resistance.
  4. Improved cholesterol and triglycerides: While high in dietary fats, the Proper Human Diet can improve your lipid profile, such as increased levels of HDL (good) cholesterol and decreased levels of triglycerides.
  5. Can eliminate PCOS: PCOS is directly linked to chronically high levels of insulin resulting from a high-carb diet. Cutting carbs reduces the hormonal trigger behind PCOS.
  6. Supports the treatment of various cancers: Certain cancers thrive on high-sugar diets.
  7. Protects against neurodegenerative diseases, including epilepsy, Alzheimer’s, and Parkinson’s disease.
  8. Enhanced mental clarity, focus, and mental health: Studies show keto diets can dramatically improve mental health conditions, reduce psychotic symptoms, and eliminate the need for mental health medications. Many other studies directly link meat eating with lower incidences of depression and anxiety.
  9. Regulates inflammation: Chronic inflammation is linked to numerous health issues, including painful/inflamed joints, heart disease, respiratory issues, early aging, diabetes, and autoimmune disorders. By reducing carbohydrate intake, the Proper Human Diet may help lower inflammation markers in the body.
  10. Supports immune function: Even short-term studies have shown an improvement in metabolic function and immune response.
  11. Provides an abundance of important fat-soluble vitamins (K, D, E) that are essential to overall physical health.
  12. Protects the glycocalyx–this delicate membrane covers the surface of every cell and plays a critical role in numerous physiological functions, including heart health, inflammation, and fertility.
  13. Reduce the incidence of AGEs (Advanced Glycation End products): AGEs occur when you combine sugar with protein or fat. This sticky compound clogs up your smaller blood vessels.

5 Tips for Success on Proper Human Diet

These five tips will help you unlock the powerful benefits of the carnivore diet.

  1. Commitment: It takes time to make the transition from a high-carb standard American diet to PHD. Give yourself at least 30 days. Then extend your commitment for another 30 days until it becomes an established eating habit. If you fall off the wagon, dust yourself off and get back up. A big ribeye drenched in salty butter usually does the trick.
  2. Join an ancestral eating community. Like-minded eaters share their successes and tips and motivate each other amidst a world of junk food temptations.
  3. Remove temptations! Don’t make an enemy out of your fridge, freezer, and pantry. Throw away all non-PHD foods, and stock up with ancestrally-aligned whole foods.
  4. Stock up! This part is fun. Fill your shopping basket with succulent meats and cheeses.
  5. Keep at it! It takes time to transform your mental circuitry into a durable habit. Take it one meal at a time, and keep going!

Proper Human Diet: The Bottom Line

Low-carb enthusiast Dr. Ken Berry asks, “Is there a proper human diet? Or can humans eat whatever they want and expect good health?

The answer is clear. The modern Standard American Diet is loaded with processed junk food, and grains and over-loaded with industrial fruits and veggies. These foods contribute to various “diseases of civilization” and autoimmune disorders.

The key to reclaiming health and wellness begins with what you put in your mouth. It makes nutritional sense to look at the whole foods that our ancestors evolved, eating as the key to reclaiming our health and wellness, one meal at a time.

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