Why even considering a fruit-based diet?
A raw, high-fruit nutrition does seem radical at first glance, but there are serious biological aspects to consider before dismissing the concept! A fruit-based way of eating is not a random new diet but rather based on human biology. Instead of another fabricated diet, we desperately need to know what the original natural human diet looks like. After all, we do have a species-specific diet, just like any other species! In the case of humans, this is a tropical fruit-based diet, which is backed up by the mounting evidence of our frugivorous nature. And finally, science is also picking up the importance of tropical fruits for health. So let’s dive into the three things we need to know to understand a fruit diet:
- Biologically, we are specialized fruit-eaters (frugivores).
- Cooking is not part of any species-specific diet in in the wild.
- Frugivores do not only fruits only.
It is self-explanatory that eating the natural diet according to one’s biology is essential for the body’s functional integrity – and thus good health. And real-life experience shows it over again: the benefits, like rejuvenation and regeneration, experienced when adopting a fruit-based diet are often astounding and undeniable.
If you are new to this, visit this overview about frugivores and frugivory here!
Biologically, humans are tropical frugivores!
Humans originated in tropical Africa (Daanen, 2016). (To understand the implications of this fact in terms of diet, it is important to note that highly frugivorous can only live in tropical forests!) Humans have not experienced significant evolutionary changes in diet-related biological traits. Only a few specific local adaptations have emerged, which enabled survival in challenging cold environments and their food sources (for example, improved milk digestion or increased tolerance for fire smoke toxins). But we adopted a cultural survival diet (cooked diet) that has far deviated from our ancestral diet and our biology.
Primates specialization in fruit-eating
It’s becoming more evident that our morphology and physiology are that of a tropical frugivorous (fruit-eating) primate: we share those traits with our closest relatives, the Chimpanzees, which are specialized ripe-fruit-eaters. Their preferred food is fruit, which makes up around 70% of their diet. Read more on the Chimpanzees dietary habits here.
Scientific American published a telling article in 2006, written by a primate researcher on the similarity between chimpanzee and human digestion and dietary biology in general, with the headline: “Many characteristics of modern primates, including our own species, derive from an early ancestor’s practice of taking most of its food from the tropical canopy.”. Katharine Milton already published a paper in 1999 in the journal Nutrition about why the diet of chimpanzees should inspire the human diet.
Adaptations to a fruit-based diet
Humans have distinct frugivore adaptations (read the full article here): a few examples are complex hands for fruit handling, dental structure, digestive system, and our positive sensory experience with ripe fruits (attractive look, smell, and taste).
We instinctually know that fruits are good for food. Even very young children instinctually are attracted to sweet colorful fruits – unaltered and raw.
Humans also have specialized biochemical features that evolved due to fruit-eating, which are fascinating and hard to deny. For example, the loss of vitamin C genes is a unique trait shared by highly frugivorous animals. The mutation has occurred analogously in those birds, bats, guinea pigs, and primates that take in a lot of external vitamin C through their diet, which made internal vitamin C production non-vital. Another example is the trichromatic specialized color vision (optimal to detect fruits) shared with our primate family.
All wild species eat a raw diet
Additionally to our obvious frugivorous biology, consider this simple species-appropriate instinctual test: everything that is appealing straight from nature is food optimally suitable for humans. Everything that needs to be processed to become safely edible and tasty – like cooking, mixing, or seasoning for flavor – is not really human food. This concept is simple, but it is how we analyze the diets of animals in the wild – instinctual knowledge.
No animal needs to cook their food to survive, but calling the (raw) diet of elephants, monkeys, or seals in the wild “radical” or “extreme” does not cross our mind, ever – only with humans, this has become a thing. And – before you ask – humans have not adapted to a cooked diet, in a way that we are hooked to it. In fact, the only adaptations to cooked foods in humans, are a decreased immune response to it and higher tolerance to fire smoke toxicity! Read more on the topic here.
Differences between “frugivore” and “fruitarian”
What is the difference between frugivore and fruitarian? Simply put, a frugivore diet is what the frugivorous species naturally eat in the wild. In contrast, a fruitarian diet is a fruit-only dietary concept that people can choose to adopt.
A frugivore diet is not a fruit-only diet
Frugivore and fruitarian is related and often confused, but there are significant differences in food that are included. Hence knowing the difference is important to make informed decisions when you want to adopt a fruit-based diet:
| Frugivore | Fruitarian | |
| Concept | Natural dietary pattern of frugivores observed in the wild | Diet based on our frugivorous biology and our natural instincts |
| Foods | Tropical fruits, Greens, Tubers, Nuts, Seeds, Insects, Eggs, Meat (?) | Fruits |
| In Common | Raw, Fruit-Based | Raw, Fruit-Based |
Read more on how much animal-based foods – especially meat – chimpanzees consume here.
Conceptual difference between “fruitarian” and “frugivore”
Besides the types of foods included in a frugivore and fruitarian diet, there are essential differences in the underlying concepts:
What is a frugivorous diet?
The “frugivore diet” is the human diet, naturally determined by our biological makeup. It is our species-appropriate diet. There is no such thing as the frugivore diet. We might more accurately call it a frugivore’s diet, which consists of the foods that frugivorous animals eat in the wild. What this looks like for humans is not entirely clear. However, we can start using our own natural, instinctual knowledge and might get inspired by our primate family.
The natural diet of frugivorous primates varies from species to species and depends on food availability. Generally, the diet consists mainly of fruits. Additionally, they forage for nuts, seeds, greens, tubers, insects, and eggs, and sometimes also special foods like mushrooms and crabs, bark, mineral-containing mud and herbs. Hence, a frugivore diet is not necessarily vegan. It is pivotal to understand that those species live in the tropics, where they can access highly nutritious fruits, unlike in colder climates. Thus, tropical fruits are essential for a frugivorous diet, also in humans. See here why tropical fruits need to be the staple food on a fruit-based diet, and why a diet based on temperate fruits is not suitable or sustainable for us.
Thus a frugivore’s diet is not a choice – it is simply a biological “characteristic”. Humans all have traits that suggest a frugivory nature – we cannot choose or change that. And… eating a carnivore or granivore (grain-eater) diet – won’t make us carnivores or granivores. We then just “eat outside our biology”.
What is a fruitarian diet?
“Fruitarian” is a fruit-only diet we define and choose to adopt. Fruitarians choose this diet for the well-being of animals, the plants, and their own health, too. Unlike a frugivore diet, the fruitarian diet is a concept or principle like “vegan”. Fruitarians are aware that fruits are the only food that plants offers to the consumer in a symbiotic relationship between seed-disperser and plant – the plants benefits too! As a consequence, fruits that have coevolved with its consumer have no toxic defense chemicals. Other plant parts are being protected from consumers, especially grains, which contain their embryos, ensuring the next generation of the plant. But also, most green parts and roots are not “willing” to be eaten and thus contain many secondary metabolites that are meant to put-off consumers
What frugivore and fruitarian have in common is – of course – the focus on fruits and the knowledge that tropical fruits are what best sustains our frugivorous body. Also, the two diets strongly overlap: Chimpanzees, for example, seem to have extended periods when they only eat fruit depending on fruit availability. In fact, other type of foods might only be their fallback foods, when fruit is not available (Watts et al., 2011). The consensus in scientific literature is that the Chimps’ preferred food is ripe fruit! Therefore, it is highly likely that humans also can sustain themselves for an extended period on high-quality, ripe tropical fruits only! Which equals the fruitarian diet. Hence, the frugivore diet is sometimes identical to the fruitarian diet, depending on fruit availability in the wild. However, if the body finds nuts and greens appealing, use your instinctual knowledge.
A fruit-based diet is our natural diet, but we need to know how to do this right!
Because humans share most of the dietary biological traits with other frugivorous primates, the significance of eating a diet based on fruits is gaining momentum. However, this diet can easily go wrong, if we do not know what we do! Yes, we are tropical frugivores, but we are alienated from nature and live outside our natural habitat and thus need to relearn what our species-appropriate diet really looks like. Just jumping into a fruitarian diet and “eat fruits only” will probably not be sustainable in the long run, especially when living outside the tropics, where it is hard to get access to high-quality ripe tropical fruits.
However, when done informed and carefully, step by step increasing ripe delicious tropical fruits into your diet, a species-specific fruit diet could be just what you have been looking for…
To avoid common beginner mistakes, also check out the free fruit-diet guide:
Go to How to do the Frugivore Diet
References
- H.-Y. Ahn, H.-D. Cho, Y.-S. Cho, Comparison of antioxidant effect and phenolic compounds in tropical fruits. SN Applied Sciences. 2 (2020), doi:10.1007/s42452-020-2927-5. (link)
- H. A. M. Daanen, W. D. Van Marken Lichtenbelt, Human whole body cold adaptation. Temperature. 3, 104–118 (2016), doi:10.1080/23328940.2015.1135688. (link)
- K. Milton, Diet and primate evolution. Scientific American (2006) (available at https://www.scientificamerican.com/article/diet-and-primate-evolution-2006-06/). (link)
- K. Milton, Nutritional characteristics of wild primate foods: Do the diets of our closest living relatives have lessons for us? Nutrition. 15, 488–498 (1999), doi:10.1016/s0899-9007(99)00078-7. (link)
- K. Cutlip, Did ripening fruit help hominids develop complex hands? Smithsonian Insider (available at https://insider.si.edu/2016/05/did-ripening-fruit-help-hominids-develop-complex-hands/). (link)
- T. H. Jukes, J. L. King, Evolutionary loss of ascorbic acid synthesizing ability. Journal of Human Evolution. 4, 85–88 (1975), doi:10.1016/0047-2484(75)90002-0. (link)
- Trichromacy. Wikipedia (2023) (available at https://en.wikipedia.org/wiki/Trichromacy#Humans_and_other_animals_that_are_trichromats). (link)
- L. S. Carvalho, D. M. Pessoa, J. K. Mountford, W. I. Davies, D. M. Hunt, The genetic and evolutionary drives behind Primate Color Vision. Frontiers in Ecology and Evolution. 5 (2017), doi:10.3389/fevo.2017.00034. (link)
- David P. Watts, Kevin B. Potts, Jeremiah. S. Lwanga, John C. Mitani, Diet of chimpanzees (Pan troglodytes schweinfurthii) at Ngogo, Kibale National Park, Uganda, 2. Temporal Variation and Fallback Foods. American Journal of Primatology. 74, 130–144 (2011), doi:10.1002/ajp.21015. (link)
