Our bodies are miracle machines that can grow muscles from food, weave stories into dreams, and transform oxygen from air. Biology - the science of understanding the body’s processes - backs the practices and tools that have drastically improved human quality of life. Common ways we use science to optimize our bodily functions include balanced nutrition, vitamins, and sleep or exercise protocols.
Although the general public knows plenty about bodily functions like building muscle, mental health disorders remain largely taboo and full of misinformation. This is a shame because mental health is one of the most pressing issues of our modern world: 29% of US adults report suffering from depression in their lifetime and ~14% of US adults are currently on antidepressants. My goal is to teach you how the body develops mental disorders and how you can use the same mechanism to heal the body. By understanding this process at its core, we can take the right steps to lessen our mental suffering and drastically improve our quality of life.
Humans (homo sapiens) are bound by the same laws of physics, survival, and fear as all animals. Despite our big brains that allow for complex coordination, language, and culture, we’re still at the mercy of our primal, animalistic survival instincts when it comes to mental illness.$^{71}$
This limitation of the human body is called evolution, a process that takes millions of years to produce significant changes to our brains and bodies. Humans evolved for a nomadic hunter-gatherer lifestyle, the default human way of life for approximately 97% of our existence.$^{70}$ In stark contrast, our culture evolves rapidly by the second, putting us in situations completely foreign to our animal bodies. By viewing our mental health problems through our animal body’s needs not being met by modern life, we can begin to make progress at the root cause.
Figure 1: Timeline of human history. Figma Link
Our current way of living by Western civilization and agriculture has only been practiced for around 1500 years and 12,000 years respectively. That means for the other 99.5% of our existence without Western culture and 96% without agriculture, human beings lived drastically different lives. $^{24}$ It is not just improbable, but fundamentally impossible, that humans have evolved in the past few 1500 years (<0.5% of existence) to live a modern lifestyle.
Here’s what a day in our ancestors’ lives, when our evolutionary needs matched our day-to-day activities, may have looked like:
As the first rays of sunlight crest the horizon and seep through the old forest trees, the birds start to chirp, waking the world from its slumber. You wake to the soft sounds of our small tribe stirring in the morning light. Your group of about 30 people — men, women, and children — begins preparing for the day’s work. Living off the land, you all scatter into the forest in pairs or small groups, gathering fruits, nuts, vegetables, and mushrooms, while a few of the best hunters track small game or follow the trails left by larger predators, hoping to scavenge their kills. The children, too young to hunt or gather, play nearby, imitating the adults by practicing with small sticks and stones, always under the watchful eyes of the tribe. The mornings are filled with activity, but the work rarely lasts more than a few hours. By midday, you return to the camp, sharing food communally. The older tribe members tell stories or offer guidance, and everyone contributes to cooking or caring for the young ones.
As evening falls and the sky darkens, the tribe sits together around the fire, talking and relaxing, their bellies full from the day’s harvest. In the distance, a predator’s howl echoes, a reminder that you are not the only one here. But you sit safely in numbers, knowing that cooperation has kept you alive for generations. As the stars twinkle overhead, you gaze up, contemplating the spirits of the animals and plants that have provided for you today. You believe that every living thing is connected, that the Earth has a spirit, and so you tread lightly, taking only what you need, giving thanks in quiet rituals under the open sky. The children fall asleep, cradled by their mothers, while the rest of us watch the night unfold, connected to the land, the sky, and each other.
Like all other animals, this is how humans (homo sapiens) lived for 290,000 years: taking only what we needed while fulfilling our basic evolutionary needs.$^{72}$
| Our Evolutionary Needs | Why we need it | Our ancestors’ practice |
|---|---|---|
| **Social Connections** | We crave strong social ties and a sense of belonging | Lived in close, tight-knit communities that cared for one another |
| Purpose | We crave roles that serve a higher purpose of providing for others | Had clear roles in the tribe - hunting, gathering, protecting for each other |
| Physical activity and nature | Exercise and time outdoors improve our mood and body - mind connection. | Constantly moving—hunting, gathering, and foraging in nature. |
| Simplicity | We adapt quickly to wealth, so it doesn’t provide lasting happiness. | Lived minimally, focusing on survival needs like food, shelter, and safety. |
| Mindfulness | Strengthens the connection between our mind and body. Reduces anxiety and increases focus | Practiced rituals, connection to nature, communal living, and spiritual practices through focused tasks, meditation, or attentiveness to their environment |
| Spirituality | Provides a framework for peace, cooperation, understanding life’s challenges, and building resilience | Connected deeply with the natural and spiritual worlds with rituals and natural plant medicines, maintaining a sense of harmony and balance with the forces they believed governed their lives. |
| Gratitude and Compassion | Human survival depended on mass cooperation | Depended on the generosity and compassion of others for survival. |
Figure 2: Our basic evolutionary needs: how we fulfilled them in the past
Ancient life sounds pretty awesome. That being said… there were also other days when we faced predators like bears and had to run, hide, or fight to stay alive. Ironically, the brain’s ancient survival system that kept us alive is now one of our greatest sources of modern-day suffering. $^{73}$