Humans As Frugivores

Exploring Evolutionary, Anatomical
& Behavioral Evidence

Despite the abundance of easily-accessed, irrefutable evidence that humans’ natural diet is fruit, the debate over the optimal diet for humans continues. Since the birth of the internet, many false prophets have arisen, claiming fame and fortune through misleading the masses into believing their diets should match the dogs and cats that share their household habitats.

These deeply flawed dietary recommendations have led those who followed this ‘bad idea’ to suffer a myriad of health complications that include pancreatic, bowel, breast, ovarian, prostate and testicular cancer as well as liver disease, kidney and heart failure, along with a host of other nervous system diseases such as Parkinson and ALS.  These dietary-based disease conditions have resulted in the premature deaths of hundreds of millions of people who have been deceived by dangerously inaccurate advice that tells them it is a good idea to deviate from our natural dietary fuel of fruit, soft leafy greens, nuts and seeds.

Peace begins on our plates by removing
the violence of using Animals for food, fur or fun

Even in the early stages of adopting the first communitarian principle and practice of ‘Evolved Living Nutrition’, those on the path to seeding the promised era of perpetual peace through shared prosperity, will understand the need to forcefully condemn those who divert people from the path of ‘Eating from the Living Trees.’

The motivation to align with the lifestyle and love-style of evolved socio-economic and ecological principles and practices underpins the drive to acquire mastery, and thereby practical application of the scientifically-proven knowledge that humans are natural frugivores. Through understanding the evolutionary traits, anatomical structures, and innate behaviours that align with a fruit-based diet, those adopting a cruelty-free diet and lifestyle can do much to lead people back to the truth of why for health, longevity, compassion for the animals and responsible stewardship of the planet, humans are best suited to ‘eating from the living trees’.

While the majority of corporately-funded medical factions remain entrenched in advocating for an omnivorous diet rich in animal products; every year, more and more doctors and nutritionists who are free to follow ‘truth in science’, turn over a new leaf in their practices to direct those suffering illness to heal through adopting a cruelty-free plant-based, or even a fruit-dominated diet.

Evolutionary Evidence

Human beings belong to the order ‘Primates’, which includes apes, monkeys, and many frugivorous species that rely heavily on the consumption of fruits and leafy greens to satisfy their dietary needs. Fruits comprise a large portion our closest relatives, chimpanzees and bonobos, diets (Hohmann & Fruth, 2008). From an evolutionary perspective, humans share a common ancestor with these apes, suggesting that our dietary preferences may have evolved from similar fruit-heavy patterns (Sayers & Lovejoy, 2008).

Studies on primate feeding behaviour support the hypothesis that the diets of early hominins consisted predominately of fruits, contributing to the evolution of modern human nutrition (Milton, 1999).

Genetic Legacy of Frugivory

Certain genetic traits link humans to frugivorous diets. For instance, humans possess a higher number of copies of the AMY1 gene, which is responsible for producing amylase, an enzyme that breaks down starches. This adaptation is thought to have been advantageous as humans evolved to consume more starch-rich foods, including some fruits (Perry et al., 2007). Moreover, humans, like other primates, are unable to synthesize vitamin C due to a mutation in the GULO gene, which is responsible for producing the enzyme required for vitamin C synthesis (Drouin, Godin, & Page, 2011). This inability further suggests that our ancestors relied heavily on fruits, which are rich in vitamin C and other essential nutrients, as a dietary staple (Milton, 1999).

Human Anatomy: Teeth, Jaw & Digestive System

Teeth & Jaw Structure

One of the most compelling pieces of evidence that suggests the human species are natural frugivores is the structure of our rounded and blunt teeth that are designed primarily for grinding and chewing, as opposed to tearing at raw flesh. By contrast, Carnivores are equipped with sharp, pointed teeth for slicing through meat, while herbivores typically have large, flat molars for grinding tough plant matter such as grasses and grains.

The relatively small and rounded canines of humans are not suited for the kind of hunting or flesh-eating that true carnivores or even omnivores like bears are adapted to (Ungar, 2012). Instead, the flat molars and spatulate (shovel-shaped) incisors in humans are well-suited for biting into and grinding soft, fleshy fruits (Lucas, 2004).

The jaw mechanics of humans also support the frugivory theory. Humans have the ability to move their jaws side to side, allowing for lateral chewing, a feature characteristic of herbivores, which is essential for grinding plant materials. In contrast, carnivores have jaws that move primarily up and down to shear through meat (Smith, 2013). This lateral chewing motion, combined with the overall dental structure, strongly suggests that early humans were adapted for a diet rich in fruits and other soft plant matter (Lucas, 2004; Ungar, 2012).

Digestive System

The human digestive system aligns with a diet predominantly based on fruit, as evidenced by the moderately long digestive tract, similar to other primates whose diets consist largely of fruit and soft leafy vegetation. Fruits are relatively easy to digest and are rich in vitamins, minerals, and natural sugars, making them an efficient food source for primates, including humans (Milton, 1999). In contrast, carnivores possess relatively short intestines designed to quickly process meat and prevent it from decaying inside the body, while herbivores have much longer intestines to break down fibrous plant material (Chivers & Hladik, 1980).

Moreover, the relatively low stomach acidity in humans, compared to obligate carnivores, further suggests that humans are not optimized for consuming and digesting large amounts of animal protein. Carnivores, such as lions, require much stronger stomach acid to break down meat and prevent bacterial growth, whereas the milder acidity in humans is more suited to digesting plant-based foods (Beasley, Koltz, Lambert, & Tamura, 2015). These digestive traits strongly indicate that human evolution favored a diet rich in fruits and plant matter rather than one heavily based on meat consumption.

Craving for Sweetness: A Biological Drive

As the majority of us know from personal experience, humans have an innate craving for sweet flavours, and this preference is not random. Sweetness serves as a direct signal of energy-rich food. Throughout evolution, fruits—rich in natural sugars—provided a reliable source of calories, and our bodies became wired to seek them out (Drewnowski et al., 1992). In evolutionary terms, the preference for sweetness likely developed as a survival mechanism, guiding early humans toward the most energy-dense foods available in nature (Leiberman, 2013). While refined sugars in modern processed foods can lead to unhealthy dietary choices, the root of our cravings for sweetness lies in our frugivorous ancestry, where seeking out high-sugar fruits was advantageous for energy and survival (Katz, 2012).

The Dopamine Reward System

Sweet foods trigger dopamine release in the brain, providing a sense of reward and pleasure. This activation of the brain’s reward system encouraged early humans to seek out nutrient-dense fruits as a means of survival (Small, 2010). The core drive for sweetness aligns with a natural inclination toward fruit consumption, which historically offered a healthy source of sugars along with essential nutrients (Moss & Grandi, 2013).

However modern processed foods exploit this system by providing concentrated sources of sugar, which are far more potent than naturally occurring fruits, leading to overconsumption (Avena, Rada, & Hoebel, 2008).

Biochemistry of Fruit Consumption

Fruits are nutrient-dense, providing an abundance of vitamins, minerals, and phytonutrients that are vital for human health. They are rich in dietary fiber, which supports digestive health, helps regulate blood sugar levels, and promotes satiety (Slavin, 2013). Additionally, fruits are high in antioxidants, such as vitamin C, flavonoids, and carotenoids, which protect the body from oxidative stress and reduce inflammation (Boeing et al., 2012). The biochemical composition of fruits appears almost perfectly aligned with human nutritional needs, offering essential nutrients for maintaining overall health and preventing chronic diseases (Liu, 2013).

Fruit and Gut Health

The fiber in fruits fosters a healthy microbiome by promoting the growth of beneficial gut bacteria. Human gut flora thrives on the fibers and prebiotics found in fruits, which are fermented by gut bacteria and converted into short-chain fatty acids (SCFAs), such as butyrate, that are vital for gut health (Flint et al., 2012). In contrast, high-protein and high-fat diets based primarily on animal products can promote the growth of harmful bacteria, leading to increased inflammation and a higher risk of diseases such as colorectal cancer (David et al., 2014). SCFAs derived from dietary fibers in fruits help maintain gut integrity, reduce inflammation, and play a protective role against gastrointestinal disorders and colorectal cancer (Louis & Flint, 2017).

Behavioral & Cultural Evidence

Many traditional human societies have relied on fruit as a key dietary component (Murdock, 1959). In tropical and subtropical regions, where fruits are abundant, early humans had year-round access to a wide variety of fruits (Piperno & Stothert, 2003). Some modern-day hunter-gatherer societies, such as the Hadza in Tanzania, also derive a significant portion of their diet from wild fruits (Hawkes & Paine, 2006). While modern agriculture and the rise of animal husbandry have diversified human diets, our basic physiology has not changed much since our frugivorous ancestors (Wrangham & Conklin-Brittain, 2003). This is why fruits remain a key part of healthy diets, even in cultures that have incorporated more meat and processed foods (Bazzano & Li, 2011; Cordain & Eaton, 2000).”

Comparative Biology

The study of comparative anatomy between humans and other animals can offer insights into dietary adaptations (Darwin, 1859; Cerny et al., 2015). When we compare the anatomy of humans to that of true carnivores (such as lions) or even omnivores (like bears), the differences are striking (Kelley et al., 2015). Carnivores and omnivores have claws for hunting, sharp teeth for tearing meat, and short digestive tracts for rapid digestion (Smith et al., 2015). In contrast, humans, like other frugivorous primates, have features more suited for gathering and consuming fruits, such as dexterous hands for picking and peeling fruit, and a sense of taste that gravitates toward sweet and sour flavors (Srinivasan et al., 2012; Maffei et al., 2017).

Embracing Our Frugivorous Nature

Humans have evolved as frugivores, evidenced by our anatomical features, genetic makeup, and cravings for sweetness. Our teeth, jaw mechanics, and digestive system are all adapted for the consumption of fruit, while our innate desire for sweet flavors is rooted in evolutionary survival strategies that prioritized energy-dense, nutritious foods. While the modern diet has evolved to include a wide range of foods, many of which are far removed from our evolutionary roots, a fruit-heavy diet may still be the most natural and beneficial for human health.

The idea that humans are frugivores may not be mainstream, nonetheless, as we continue to study human evolution and biology, this theory provides a compelling explanation for why fruits are such a fundamental and beneficial part of our diet.

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