What’s a Healthy Diet? Eating Well from an Evolutionary Perspective

Healthy eating is one of the most confusing, controversial, and divisive topics out there. Scroll through social media or browse wellness blogs, and you’ll find an overwhelming range of opinions, often contradictory, about what it means to eat “healthy.” From vegan, vegetarian, and raw food movements to paleo, ketogenic, and carnivore approaches, dietary tribes seem to live on opposite ends of the spectrum.

Science adds both clarity and confusion to the discussion. You’ll find well-researched studies supporting nearly every position, from vegan, carnivore, to the health benefits of seed oils. But science rarely delivers absolute proof — it can only show what a specific study, with specific parameters and subjects (or testing of specific biomarkers), has found. Add in human complexity — genetics, culture, lifestyle, and development — and the picture becomes even messier. It's impossible to control for all of the complex factors that make each person's lifestyle and health history unique. Science is incredibly useful and insightful in understanding health and nutrition, but results are often cherry-picked to support any specific health bias, and confounding variables can be easily missed or overlooked.

A healthy diet isn’t a one-size-fits-all approach. Human beings are drawn to neat, clear-cut ideas about health because uncertainty is uncomfortable. We naturally want confident and definitive answers to complex questions about health and longevity (and numerous other complex issues). “Good vs. bad” is easier to understand and accept than contingency, context, or ambiguity. Charismatic voices that promise certainty feel reassuring, especially when it comes to something as fundamental as food. As a result, there's a lot of money to be made selling ideologies and, even better, a miraculous product that bundles health and longevity into a single daily dose.

But to really understand what “healthy eating” means, we need to zoom out—beyond modern dietary tribes, trends, and marketing propaganda—and look at the long arc of human evolution. From that vantage point, a more grounded and biologically coherent picture emerges. While certain genetic and physiological shifts have occurred since the rise of agriculture and modern food processing—such as changes in dentition, jaw structure, and lactose tolerance—our deeper adaptations to whole-food nutrition and cooked diets run much deeper.

For instance, the human digestive tract evolved in tandem with the mastery of fire and cooking, leading to shorter intestines, smaller teeth and jaws, and a reduced gut volume—an evolutionary energy trade-off that supported the development of a more metabolically costly and neuronally complex brain. These ancient adaptations to cooked and nutrient-dense foods are deeply encoded in our biology and unlikely to change anytime soon. Seeing the bigger picture of human dietary evolution offers far more clarity than getting lost in the noise of modern diet trends and conflicting data.

A (Very) Brief Evolutionary History of the Human Diet

Our species, Homo sapiens sapiens, evolved from earlier upright-walking apes (hominins) over the course of more than a million years. From them, we inherited key traits — bipedalism, binocular vision, dexterous hands — and, importantly, a highly adaptable diet. While we no longer spend time in trees, we can still effectively climb them and hang from branches with long arms and grasping hands, all traits we share with modern primates living today.

Early human ancestors were chimp-like apes living in the region of modern-day Africa, and we still share most of our DNA with modern chimpanzees, bonobos, and gorillas. Like them, we’re omnivores capable of eating a wide variety of foods. But while we share many features, our digestive systems and skulls tell a different story. Gorillias, for example, have giant skulls with fin-like bone structures on top (called sagittal cresting) because they're equipped for a much different diet than we are.

Western gorilla (Gorilla gorilla) skull at Barcelona Zoo (Catalonia, European Union). Note the large canine teeth, jaw, and cresting on the top and sides of the skull, created by powerful masseter muscles—biological equipment for shearing and shredding dense, raw vegetation.

In this line-up, starting with the smallest, we have a macaque (monkey), an orangutan, a chimpanzee, and lastly, a human skull. Note the vast difference between the human skull shape (and particularly the mouth and teeth) with that of other primates. The chimpanzee (directly next to the human skull) is one of our closest living primate relatives. It has much larger and sharper teeth and a protruding maxilla (bony region below the nasal cavity); the zygomatic arch (cheek bones) are much larger and more robust for stronger jaw muscles. Image source: Christopher Walsh, Harvard Medical School, derivative work: TimVickers, CC BY 2.5, via Wikimedia Commons

Gorillas and chimpanzees spend much of their day eating and digesting raw vegetation. Their massive jaws, canine teeth, and specialized guts are designed for this. Humans, by contrast, can eat quickly and expend energy elsewhere — walking, hunting, building, thinking. That shift was monumental. While you'll find other primates spending much of their day sleeping and resting, humans are far more active and productive, equipped to spend long hours expending immense energy on various complex tasks and projects.

Somewhere along the evolutionary line, our ancestors (distant hominins, long before humans emerged) learned to process and cook food. Cooking was revolutionary: it made previously inedible foods digestible, increased calorie availability, and reduced the energy demands of digestion. It also freed time for other pursuits — like toolmaking, socializing, and eventually, thinking more complexly. Civilization would not be possible without this vital shift in human evolution. And it resulted in hominins leaving Africa and spreading across the globe.

Cooking, fermenting, drying, and other forms of food processing were the first steps in “outsourcing” digestion. Our brains, which now consume approximately 20% of our daily energy, could only have evolved in tandem with this dietary revolution, resulting in brains with a higher number of densely packed neurons, which allow for more complex intelligence, movement, and social organization. It's not actually the size of the human brain that makes us unique compared to other animals and primates, it's the greater efficiency it evolved as a response to more diverse enviornmental conditions, and the unique ways we digest and metabolize food reflects this efficiency.

Adaptability: The Cornerstone of Human Nutrition

Humans are one of the most adaptable eaters on Earth. From the frozen tundras of Ice Age Europe to the tropical forests of Africa and Asia, we learned to thrive on whatever was available — meat, tubers, grains, nuts, seafood, and insects. Distantly related ancestors, like Neandertals, appeared to subsist at times on the marrow found in animal bones, exploiting whatever food source they could find.

Yet there’s a difference between surviving and thriving. Early humans and other early hominins often lived short, injury and disease-prone lives. They survived on what they could find, not necessarily what was ideal. Today, our goal isn’t just survival — it’s long-term vitality, fitness, cognitive clarity, and disease prevention.

Different populations adapted circumstantially to different foods. For example, Inuit peoples thrived on high-fat, animal-based diets, while many African and Asian groups have thrived for millennia on starch-rich plant foods. So there isn’t one “ancestral” diet that fits everyone, and humans are capable of surviving on a variety of dietary adaptations, which is what led to our successful global reach. What we do share is a universal adaptation to whole, nutrient-dense foods — and a need for variety. Additionally, since non-human ancestors had already pioneered digestive outsourcing, we also rely heavily on technological means of food processing, such as cooking.

Unique factors, such as certain genetic predispositions, metabolic conditions, and diseases, will require adjustments and more specialized approaches, but all humans will fare better on some variation of a diverse, whole-food diet that maximizes the bioavailability of the foods they consume. This is always a good starting point.

Why Whole Food Diversity Matters

Despite our adaptability, human health declines rapidly on ultra-processed foods. An optimal and healthy diet is one that focuses on simple, natural ingredients. Our evolutionary advantage lies not in eating everything, but in eating real food — whole plants and animals prepared in ways that make nutrients more accessible.

Cooking, fermenting, and using natural fats to extract nutrients from plants are ancient techniques that remain essential today. Humans aren’t well equipped to live on raw plant foods alone; we lack the specialized digestive systems of gorillas or ruminant animals that can ferment dense vegetation in multiple stomach chambers. These species are built to thrive on raw leaves and shoots — but we aren’t.

For humans, a healthy diet is one centered on cooked plant foods and whole animal foods, with as much variety as possible. Early hunter-gatherers ate seasonally, often consuming hundreds of different species throughout the year. In contrast, modern industrial diets rely heavily on a narrow set of staples — wheat, rice, corn, potatoes, chicken, beef, and pork.

The less diverse your diet, the less diverse your gut microbiome — and the weaker your long-term resilience. Additionally, exposure to a wide range of complex phytochemicals produced by edible plants (which vary from season to season) also offers numerous other health benefits. Diversity is nature’s insurance policy.

Still, incorporating some raw plant foods offers unique benefits that cooking can’t replace. Fresh fruits (like citrus and berries) and leafy greens supply vitamin C, enzymes, and phytonutrients that are sensitive to heat. Chewing fibrous raw vegetables and tougher foods (like nuts) also supports jaw function and facial strength, while stimulating neural pathways linked to brain health and even neurogenesis.

The ideal human diet, then, combines both — the nourishment of well-cooked, easily digestible meals and the vitality of raw, living plant foods — balanced with the seasonal rhythm of nature.

Eating Closer to Our Ancestral Roots

Despite the complexity of modern nutrition debates, eating healthy is actually simple:

Do your best to eat the kinds of foods humans have been eating for most of our evolutionary history, most of the time.

That means:

• Whole, unprocessed foods — both plant and animal

• Cooked or fermented foods to aid digestion and nutrient absorption

• Seasonal and diverse food choices

• Include fats from whole food sources (like grass-fed butter, whole-fat milk and yogurt, ghee, olive oil, avocadoes, and coconut oil)

When it comes to fats, the conversation often reduces to “good” versus “bad,” but the reality is more nuanced. Saturated fats, seed oils, animal fats, and plant-based oils don’t affect everyone the same way, and their impact depends on what else is being consumed, a person’s metabolic state, and their genetic tendencies. For example, someone who is active and insulin-sensitive may tolerate saturated fats differently than someone with chronic inflammation or genetically elevated LDL levels.

The negative health outcomes associated with seed oils, for example, may stem more from the ultra-processed foods they’re commonly found in—such as fried, packaged, or refined snack products—rather than from the oils themselves (though they are less shelf stable and should never be reused for cooking). Likewise, saturated fats have been unfairly vilified in studies that often failed to distinguish between whole-food sources (like dairy, eggs, and pasture-raised meats) and highly processed foods (like pastries, processed meats, or fast food). Much of the early research also relied on limited lipid biomarkers, such as total cholesterol or LDL-C, which we now know do not fully capture the picture of cardiovascular risk.

There is clear evidence that hydrogenated seed oils (which contain harmful trans fats), especially when used for deep frying at high temperatures, should be avoided as much as possible. However, for the most part, rather than isolating a single type of fat as the problem or solution, it’s more accurate to examine overall dietary patterns, food quality, and individual biology. In most cases, emphasizing whole-food sources of fat—whether from olives, fish, nuts, eggs, avocados, or grass-fed and pasture-raised animals—offers more reliable health benefits than following a one-size-fits-all rule about what counts as a “healthy” fat. As a personal bias (in my own diet), I prefer traditional fats as close to whole food sources as possible, given their extensive use by early humans and their limited processing.

Humans are omnivores. We evolved to eat both plants and animals. While short-term vegan or carnivore diets can show benefits for some people, they tend to lack long-term balance. Nutrients like vitamin B12, iron, and certain fatty acids are vital to human brain and nerve health — and these are found primarily in animal foods.

Early humans ate the whole animal, not just muscle meat. With refrigeration nonexistent, animals had to be quickly consumed, in the field, and everything was well utilized. Organ meats, bones, and connective tissues supplied amino acids, minerals, and fats that modern diets often lack. A keto or carnivore diet devoid of diverse animal parts is not going to be complete.

Finally, quality matters. Grass-fed, pasture-raised, and organic foods reduce exposure to synthetic chemicals and deliver higher nutrient density. They’re simply closer to how food has always existed in nature.

In Conclusion

A healthy diet doesn’t come from dogma or dietary tribes. It comes from aligning with the biological wisdom of our species — eating a diverse range of whole, properly prepared foods that have sustained humans for millennia. You don’t have to eat perfectly or stress about every bite. Focus on eating real, nutrient-rich food most of the time, and your body will thank you for it.

Here are some key principles to put it all together:

Whole foods: Focus on prioritizing a variety of whole plant and animal foods rather than highly processed foods. Choose whole grains such as whole wheat pasta and bread, brown rice, or quinoa. Reduce or eliminate highly refined carbohydrates and highly processed meats. For example, try to avoid deli meats and sausage; choose minimally processed sourdough over white bread.

Cooked foundation: Most plant foods and all animal proteins are gently cooked or stewed for optimal digestion and nutrient extraction. Boiling or baking harder vegetables, such as potatoes, squashes, beets, and carrots, is also ideal, preferably for an hour or more. I personally consume both cooked and raw leafy greens, sometimes boiling kale in shallow water for over an hour to extract as much of its nutrition as possible.

Raw accents: Include a few raw fruits or vegetables daily for vitamin C and phytonutrients. Chewing harder foods (such as nuts, seeds, or beef jerky) is beneficial for jaw/facial structure, as well as brain health.

Fermented foods: A small serving of fermented vegetables or cultured dairy supports the microbiome.

Traditional whole-food sources of fat: Use good-quality olive oil, ghee, butter, tallow, or coconut oil. Go with whole-fat, grass-fed, or organic milk, yogurt, and sour cream instead of low-fat versions. Check ingredient lists in processed foods, especially for hydrogenated seed oils, and avoid fried foods made with them.

Strike a macro/micro balance with meals: include a balanced amount of protein (both animal and plant-based), fats, and carbohydrates (both simple and complex), such as starches, whole grains, and lower-carbohydrate vegetables.

Try wild foods: Experiment seasonally with wild foods like weedy herbs (dandelions or cooked nettles) and animals (like Elk, Bison, or Wild Sardines). Less domesticated species of plants and animals have better nutritional profiles and are more closely aligned with early human diets.

However, it’s important to point out that a healthy diet is only one piece of the puzzle when it comes to long-term wellbeing. Genetics, metabolic health, and lifestyle habits—like movement, sleep, and stress patterns—shape how any given person responds to different foods. Two individuals can eat the same meal yet show completely different biomarker responses depending on factors like insulin sensitivity, fitness level, baseline inflammation, or inherited cholesterol patterns. That said, a diverse, whole-food diet is one of the most reliable foundations to build on, because it supports metabolic flexibility and reduces the burden of ultra-processed ingredients. But diet alone can’t compensate for chronic inactivity, poor sleep, high stress, or genetic predispositions. Understanding health in context—what someone eats, how they live, and what their body is working with genetically—provides a much more accurate picture than nutrition in isolation.

If you’d like personal guidance in rebalancing your diet or improving your health through food and lifestyle changes, I offer herbal and wellness consultation sessions where we can design a plan that fits your unique body and lifestyle, taking into consideration a range of holistic factors.

Here are some sample menus of what a broad, whole food diet close to evolutionary patterns might look like:

Breakfast:

Example 1

• Pasture-raised eggs, lightly scrambled in grass-fed butter or ghee

• Sautéed greens (spinach, kale, or chard) with olive oil and garlic

• A side of fermented vegetables (like sauerkraut or kimchi)

• Fresh berries or a small piece of seasonal fruit for raw fiber and vitamin C

Example 2

• Steel-cut oats soaked overnight and cooked with whole milk, cinnamon, and chia seeds

• Topped with walnuts, sliced apple, and a drizzle of honey

• Green tea or nettle herbal infusion

Lunch:

Example 1

• Wild-caught salmon or sardines (rich in omega-3s)

• Roasted root vegetables (sweet potatoes, carrots, or beets)

• Mixed greens with raw vegetables (tomato, cucumber, sprouts) dressed with olive oil and lemon

• A small portion of fermented food for gut health

Example 2

• Leftover grass-fed beef or free-range chicken wrapped in collard or lettuce leaves (or made into a sandwich with organic whole wheat bread)

• Add avocado, shredded carrot, cucumber, and herbs

• Side of quinoa or lentil salad with olive oil, lightly salted with sea salt

Dinner:

Example 1

• Slow-cooked, crock-pot beef or lamb stew with bone broth, onions, celery, carrots, and herbs

• Served with cooked greens or steamed broccoli

• Small salad of raw arugula, dried cranberries, and feta cheese

Example 2

• Pasture-raised chicken thighs baked or cooked in a crock pot with whole garlic cloves and rosemary

• Sautéed mushrooms and zucchini in olive oil

• Mixed green salad with raw kale, shredded beets, and sunflower seeds