ENERGY SCIENCE
There are many things that make mitochondria amazing and unique organelles.
Here is a top ten fact list about mitochondria.
1) Mitochondria Do a Lot More Than Transforming Energy
Many people still think of mitochondria primarily as energy transformers or “powerhouses” in our cells. However, they have been shown to engage in more than 30 functions and behaviors.
Producing heat, sensing oxygen, making steroid hormones, triggering cell death, and sending signals to fellow mitochondria, other organelles, and other cells. These are all among the essential contributions that mitochondria make to sustain life and allow you to thrive.
The table below showcases just how diverse the roles of mitochondria are in our bodies. We previously wrote a post about the importance of recognizing the many different things that mitochondria do, and we hope this helps shift how we all think and talk about mitochondria.
2) Each Cell Contains Hundreds to Thousands of Mitochondria
The sheer volume of mitochondria in our bodies is also worth reflecting on.
To simplify the story, biology textbooks may show a diagram of a cell with a single mitochondrion or perhaps just a few. But in reality, one cell can be home to hundreds or even thousands of mitochondria.
My best estimate is that the average human body—if there’s anything like that—contains two quadrillion mitochondria. That’s 2,000 trillion little mitos, working together as a social collective to let your energy flow.
Their abundance also depends on the job a cell has to do. Cells that are more metabolically active, like liver or heart cells, tend to have a greater volume of mitochondria. And the number of mitochondria inside a particular cell isn’t fixed. It is constantly changing as damaged mitochondria are recycled, new mitochondria are created, and mitochondria fuse and divide to meet a cell’s needs.
3) Mitochondria Have Their Own DNA, and Can Release It Both Inside and Outside Cells
Among our organelles, mitochondria are unique in that they have their own genome. Compared to the more than 78,000 genes estimated for the human nuclear genome, mitochondrial DNA (mtDNA) contains just 37 genes. This tiny genome is likely a remnant from mitochondria’s evolutionary roots as free-living bacteria.
However, mtDNA doesn’t always stay inside mitochondria. When mitochondria become stressed or damaged, mtDNA can be released into the cell. It can also make its way outside of cells.
Once released, mtDNA can activate immune and inflammatory pathways. Its release into the cytoplasm, extracellular environment, or circulating biofluids has been linked to dozens of diseases. These include metabolic diseases like type 2 diabetes, neurodegenerative diseases like Parkinson’s disease, cardiovascular diseases, autoimmune diseases, and others.
DNA from our mitochondria can even insert itself into our nuclear genome, changing the DNA sequence of a cell in ways that may affect our health or lifespan.
4) There is Tremendous Diversity in Mitochondria Shapes and Forms
Most mitochondria don’t look like the familiar jelly bean-shaped mitochondrion from our favorite biology textbooks.
Inside living cells, mitochondria can appear as tiny spheres, elongated tubes, highly branched structures, and interconnected networks. And their diversity isn’t limited to how they appear on the outside. How mitochondria are structured and what they contain on the inside can also be very different from cell to cell and mitochondrion to mitochondrion.
When our group mapped mitochondria in skeletal muscle using electron microscopy, we were in awe of how diverse they were. Even within cells of the same tissue type, there was a wide range in terms of size, complexity, branching, and connectivity.
But why are they all so different? Mitochondrial structure is based on the needs of a particular cell type, but it can also change in response to stress, energy demands, and disease.
5) Mitochondria Aren’t Static Organelles — They are Constantly on the Move
Another concept that we may not appreciate when looking at static cell diagrams is the dynamic nature of mitochondria. They generally don’t just sit, tethered in one spot inside your cells. In many cells, they actively travel to where they are needed.
This is especially striking in neurons, where mitochondria may move long distances from the cell body to distant axons and synapses. To accomplish this, tiny molecular motors carry the mitochondria along stiff protein tubes, called microtubules, to their destination.
Cells can even tell mitochondria where to stop. Experiments have shown that calcium signals can act through a particular mitochondrial protein to halt their movement.
This paints a picture of the landscape inside a cell as a precisely orchestrated system where mitochondria are continuously rearranging to respond to changing conditions.
6) Mitochondria Burn Many Different Fuels
Mitochondria are remarkably flexible when it comes to fuel. They can transform energy from carbohydrates (like glucose), fats, and even some amino acids from proteins into usable energy for our cells.
In all cases, they rip off electrons from the carbon backbones of food-derived molecules and flow those electrons to oxygen.
During fasting, or when your diet is low in carbohydrates, your mitochondria can use ketones made by your liver as a source of fuel. Lactate was once thought of mainly as a waste product produced in your muscles during exercise. But we know now that it, too, can be recycled and used to help meet our energy needs.
Different tissues can use a mix of these circulating nutrients, and fuel preferences can shift based on whether you have recently eaten, are fasting, or if you are on a ketogenic diet.
This flexibility in fuels allows mitochondria to adapt to the energy sources available and to the changing energy needs across tissues. Our prior post also describes how maintaining this metabolic flexibility may be important for brain health.
7) Cells Have a Sophisticated System for Mitochondrial Quality Control
Because of the many roles mitochondria fulfill, cells must be able to closely monitor mitochondrial health. And to intervene when there’s a problem.
This is where the mitochondrial quality control system comes into play. It has multiple components that operate in parallel at different scales.
At the smallest scale, mtDNA is repaired, and damaged proteins can be refolded or broken down.
Moving up in scale, the architecture of the inner membrane folds (cristae) is regulated. And the permeability of the inner and outer membranes are tightly controlled to only let certain amounts of certain things in and out.
Mitochondria can be created (biogenesis), fuse, and divide by fission. The fission process also allows mitochondria to discard damaged portions, while keeping portions that are still healthy.
If a mitochondrion becomes too impaired, it is broken down and recycled (mitophagy).
These control systems help ensure our cells have an uninterrupted supply of healthy mitochondria at all times.
8) Mitochondria Travel Between Cells
We talked earlier about how mitochondria can travel within cells, but they can also move from one cell to another.
But how does this happen, and why?
Platelets in our blood can directly release whole mitochondria with or without a surrounding membrane. These mitochondria may travel through our circulatory system to be taken up by other cells.
Mitochondria can also move between cells through thin channels called tunneling nanotubes.
Movement of mitochondria between cells could be a way to reallocate energy-transforming resources to where they are needed most. For example, in one study, cells with severely damaged mitochondria were able to acquire healthy mitochondria from their surrounding cells. This restored the cells’ ability to transform energy.
Interestingly, mitochondrial transfer doesn’t always enhance health. Cancer cells can also steal mitochondria from immune cells.
9) Diverse Mitochondria in Different Cell Types Do Different Things
Within your body, a heart cell, a brain cell, a liver cell, and a kidney cell each are responsible for distinct tasks. As a result, their mitochondria are also specialized to perform different functions and behaviors.
Studies have found that mitochondria from different tissues contain different sets of proteins that are tailored to a cell’s regular tasks. For example, neurons are highly metabolically active, and they express higher levels of proteins involved in the transformation of energy to produce ATP.
Even within one organ, like the brain, mitochondria are specialized across different cell types. One study found differences in the regulation of hundreds of mitochondrial proteins when comparing three cell types from a region of the brain called the cerebellum.
In other words, our mitochondria are customized for the jobs they need to do. There isn’t just one mitochondrial type. There are many different mitochondrial phenotypes, or “mitotypes.”
10) Mitochondria are Targets for Emerging and Established Therapies
As we learn more about mitochondrial biology, we’re also further exploring how we can target mitochondria to treat diseases and support health.
Over the years, many biomolecular treatments have been tested. Each addresses a specific problem, such as excess oxidative stress or an enzyme deficiency.
One recent win on the drug development front for mitochondrial disease happened in September 2025. Elamipretide (Forzinity) became the first FDA-approved treatment for a rare mitochondrial disease called Barth syndrome. The drug acts on the inner mitochondrial membrane and helps improve the efficiency of energy transformation.
Researchers have also been investigating gene therapies, metabolic therapies, and transplantation of mitochondria from healthy cells.
While some of these treatments are specifically for mitochondrial diseases, others could be applied to various conditions where energy flow is disrupted.
It’s still early days for mitochondrial medicine, but I’m really excited to see this surge in interest in mitochondria as therapeutic targets.
Mitochondria do far more than keeping the lights on. They’re multifunctional, multifaceted organelles.
Our growing understanding of mitochondria helps us think more clearly about biology, medicine, health and healing, and even ourselves.
There are more beautiful videos and photos of mitochondria at MitoLife.
Great compilation of information. Being self proclaimed Mitochondriac I am preparing a community website
Amazing material!. I'll make a video with this material. Of course I'll Reference you and your excellent work. Thanks! Would you allow me to publish a translate on my own substack? We can do a Colab post too.