Hello intrepid explorer, we meet again! The adventures we shared in the Carnivore Code seem like they were just yesterday, and what an incredible journey that was. When I published the Carnivore Code—the book that details my personal, transformative experience with an animal-based diet and the science supporting this way of eating—I had no idea that it would resonate so deeply with readers. Since then, I’ve heard from many of you about how eating a carnivore diet has changed your life for the better.

Since publishing my first book, I’ve continued to learn, research, and refine my ideas, but many essential tenets continue to resonate with me deeply. Over the years I’ve learned that one of the keys to living a rich life is asking the best questions I can. No matter how much I learn, I realize there’s always more to discover. I continue to be fascinated by the puzzle of how we can eat in order to live the most radical lives possible.

I was asked recently to describe my background on a podcast. I’m a traditionally trained, board-certified medical doctor, author of The Carnivore Code, and host of the Fundamental Health podcast. I’ve spent the past few years spreading the message of the healing power of an animal-based diet, a way of eating that has helped me and countless individuals achieve a profound new level of health.

But as I responded, I came to the realization that I was probably born 300 years too late. Adventure and exploration are written into my soul. I’ve never been content to simply learn the consensus views and stop there. Whether I am in the wilderness climbing a mountain peak in the summer, backcountry skiing in the winter, or exploring deserted coastlines in search of waves, I’m always curious to see what is around the next bend, over the next ridge, or beyond the current horizon. I think I would have been better suited to a time when there were more geographic frontiers to explore, but I’m enjoying exploring scientific and intellectual frontiers today.

In addition to my love of exploration, I derive great satisfaction from sharing cool things I’ve discovered. Shared happiness is truly a special experience. From my days as a ski bum in Jackson Hole, Wyoming, I distinctly remember the effervescence I felt riding the chair lift on fresh snow days, sharing my favorite ski spots with strangers (soon to be friends) as we rode to the top of the mountain. Some of my best memories from that time in my life come from showing these newfound friends pristine powder runs and seeing the sheer joy displayed on their faces as we floated down the side of the mountain.

Though I’m not a ski bum any longer (at least not by trade), the experience of sharing something beautiful and amazing with others is no less meaningful for me. Hearing countless stories from people who have found improved health and vitality by shifting their lifestyle toward animal-based diets brings me profound joy.

This is why I do what I do.

I have been incredibly fortunate to have spent time in beautiful places and to have the pleasure of enjoying my travel and exploration thanks to a healthy body. It is my greatest hope that my work will help many more people reclaim their ancestral birthright to radical health so that they may live life to the fullest, free from the suffering of chronic diseases that limit their experience.

It’s been a little while since our last sojourn together. Shall we set off on another adventure? I think it’s time. Before we begin, I’d like to take a moment to share my overall perspective on human health and optimal wellness—starting with my personal experience of changing my diet for the better.

My Story

I grew up in a medical family with a physician father and nurse practitioner mother, which meant that topics like atrial fibrillation, heart failure, anticoagulant medications, and atherosclerosis were common dinner table conversation topics. From a young age, I would accompany my dad to the hospital. I was simultaneously disconcerted at the sickness that surrounded us in those corridors, but also intensely curious why and how these people had gotten so sick to wind up there. From childhood, I’ve been fascinated by the roots of chronic illness and interested in understanding how to correct and reverse these—for my own health and the health of my friends and family.

Despite having both parents in medicine and growing up steeped in such an environment, I too suffered from autoimmune issues beginning at a young age. I’ll never forget the loving but firm cajoling from my father to not forget the albuterol inhaler I used for my asthma, which grew increasingly worse over the years despite that and other medications. My hands, elbows, and wrists were also often afflicted with eczema, a condition that would continue to plague me for decades.

During my college years at William & Mary, I studied molecular biology and was fascinated by the power of this field to peer into the abyss of our internal workings. The intersection of biology and chemistry held me enraptured for much of my college years. Though I originally planned to go to medical school immediately after graduation, the muse of adventure called to me, and I spent a number of years exploring mountain wilderness areas across the western United States and abroad in New Zealand. I thru-hiked the Pacific Crest Trail, learned to ski and mountain bike, and even got into distance running, eventually completing multiple 50-mile races in the mountains.

This was an incredibly rich and memorable time in my life, but through it all my asthma and eczema continued to limit me on more than one occasion. When I turned to my doctors for help, the only answers I received were more inhalers, creams, and oral steroids, which temporarily ameliorated symptoms but didn’t fix the underlying problems. There was never any attention given to my diet or even the consideration that my dietary choices (which at this point in my life were less than ideal) could have possibly been driving these autoimmune issues.

As a child of the ’80s in a health-conscious family, we thought we were doing the right thing by limiting our fat intake, and no one thought about food quality or potentially immune-triggering foods. This was a time when all of the ills of Western culture were blamed on the dreaded saturated fat, and monstrosities like margarine somehow gained widespread acceptance while time-honored animal fats became demonized.

In my early 20s when I was traveling after college, I didn’t think much about my diet, and I certainly never considered the possibility that the foods I was eating could cause my asthma and eczema. It wasn’t until I went to school to become a physician assistant (PA) years later that the connections between the food I ate and my own health became more apparent.

My first foray into the world of self-experimentation with my nutrition was a raw vegan diet. Needless to say, at this point in my life I was unaware of much of the medical literature suggesting that such diets don’t provide adequate nutrients or protein. I learned this the hard way and lost 25 pounds of muscle mass while suffering from horrible gas and bloating and generally being an olfactory nightmare to be around. I feel sorry for the folks I shared an office with during this time. As if the loss of muscle and nearly debilitating gas weren’t enough, a raw vegan diet only seemed to worsen my eczema and breathing issues.

As I continued to study nutrition and health and self-experiment with my diet, I eventually realized that meat and animal foods were a critical part of the human diet and quickly regained strength and muscle mass by returning them to my diet. Over the next decade, I ate a predominantly “paleo” diet (a diet inspired by ideas surrounding a traditional, ancestral human diet) consisting of meat and vegetables and avoided dairy, grains, and beans. This seemed to help with my issues a bit, but they certainly didn’t resolve completely.

During this time, I became very interested in the roots of chronic illnesses like diabetes, heart disease, stroke, and autoimmunity. Working as a PA in cardiology, I constantly saw individuals with atherosclerosis (formation of plaque within the arteries) who didn’t get better despite the medications I prescribed. It quickly became clear that treating these issues with pharmaceuticals did little to affect the underlying process. The best-case scenario I could hope for with these interventions was to slightly slow the progression of disease, but these individuals inevitably seemed to worsen.

This wasn’t an acceptable outcome to me, and despite the fact that I worked with intelligent, well-intentioned physicians, no one seemed to be thinking about the underlying etiology of these issues or how to correct this. It was at this point in my career that I decided to return to medical school so that I would be able to create a medical practice of my own focused on correcting the root cause of chronic illness. I suspected that diet and lifestyle were the true underlying driving factors for these ailments and wanted to understand more deeply how humans should eat and live in order to truly thrive.

Though I had the best intentions and believed in the profound power of dietary change, I still hadn’t been able to correct my own issues. In medical school my eczema got so bad that it covered my wrists, elbows, and lower back, severely decreasing my overall quality of life and making it nearly impossible to work out. Because my skin issues seemed to come and go, it was difficult to pinpoint the foods that were triggering exacerbations. It wasn’t until a severe eczema flare years later during my residency that the light bulb went on and I began to look at the foods I was eating in an entirely different manner.

I knew that humans had been eating meat throughout our evolution and that the increased consumption of meat and organs appears to have been one of the major catalysts for the rapid growth of our brains over the last 2 million years. I was also aware that some plant foods like grains and beans were evolutionarily inconsistent, only entering our diets during the last 10,000 years, since the dawn of agriculture with the Neolithic revolution. But as I researched more about the diets of hunter-gatherer groups like the Hadza, Maasai, Samburu, !Kung San, and Kawymeno in an effort to learn more about a true ancestral and natural diet, I realized that their diets are quite different from the traditional paleo diet.

These groups favor two major types of food above all others: animal organs and meat (eating “nose-to-tail”) and sweet foods like honey or seasonal fruit. Despite the modern notion that the leaves of plants are beneficial for us, you won’t find kale, spinach, or other leafy greens on the menu for any of these hunter-gatherer groups. Though the !Kung San gather the mongongo nut, seeds and nuts are generally avoided by hunter-gatherer groups when high-quality foods like meat, organs, fruit, and honey are available, and grains and legumes are rare to nonexistent in their diets.

The more I thought about this, the more a new diet based on eating animals started to make sense. In an effort to protect themselves, plants contain defense chemicals meant to deter would-be grazers—chemicals that were triggering my eczema. As I researched the nutrient content of meat and organs, I discovered that these foods were incredibly nutritious and contained all of the nutrients humans need to thrive. I didn’t need to be eating huge salads to get the vitamins and minerals I needed; I just needed to eat organs and meat and could add the least toxic plant foods when I wanted, but these weren’t necessary.

I was originally apprehensive about eating a carnivore diet composed entirely of animal organs and meat, but my eczema wasn’t getting better, so I decided to give it a try. The results were astounding. Within a few weeks the chronic eczema on my arms, waist, and lower back completely cleared up and never recurred. My breathing also improved, and wheezing became a thing of the past—without any inhalers or medications. These improvements amazed me, but I was most surprised by the improvements in my mental clarity and overall mood that occurred with the shift to an animal-based diet. Prior to this dietary change, I didn’t think that I suffered from anxiety or depression, but eliminating plants from my diet and focusing on animal organs and meat led me to feel much calmer and less stressed. I’ve often joked about this shift by saying that my “likeliness to honk at someone in traffic meter” went way down.

Eating a carnivore diet challenges many of the conventionally held notions of what a “healthy diet” should be, but I felt so good eating this way that I didn’t want to stop. Thus began my fascination with and dedication to an animal-based style of eating. In the months and years that followed, I immersed myself in the clinical and nutritional literature and discovered that so much of what I’ve been told about healthy eating is flat-out wrong. I also began to believe more strongly that if we as humans can understand what is truly a “species-appropriate” diet for humans, we will have found an incredibly powerful tool for reversing the epidemic of chronic illness that we suffer from today.

My journey is not unique. There are now tens of thousands of people who have benefitted from animal-based diets. My greatest hope is that this cookbook will help millions more understand and incorporate these concepts into their own lives so that they may also attain optimal health and the highest quality of life possible.