Aging is a complicated process that isn’t attributed to just one determining factor.  

However, researchers today have been looking for answers on the molecular level to understand the aging process more clearly. And scientists have gravitated towards the mitochondria, a powerful organelle within the cell, as the subject of study.  

 

What are mitochondria? 

The mitochondria are the “powerhouse of the cell.” They generate 90% of your cell’s energy, operating like miniature power plants. Without them, your cells would cease to function.  

 

How do mitochondria generate energy? 

Your mitochondria generate their energy by turning the macronutrients from your food, carbohydrates and fatty acids, into an energy storage molecule called ATP (adenosine triphosphate).  

ATP molecules are like supercharged batteries, waiting to release their bountiful energy at a moment’s notice. But why do your mitochondria create stored energy in these molecules instead of straight “pipelining” power to all the necessary parts of the cell? 

Portability.  

These ATP molecules can travel to all the essential parts of the cell. Once they arrive at their destination, they break apart, creating a surge of energy for use by their nearby neighbors.   

 

What role do mitochondria have in aging? 

There are many functions in the cell that require the energy created by our mitochondria. If that energy source were to be interrupted in some way, our cells would be in trouble. Much like a rolling blackout in a bustling city, a lack of power could impede several vital operations in your cells.  

When your mitochondria don’t behave the way that they should, it’s called mitochondrial dysfunction. And mitochondrial dysfunction has been proposed as one of the nine hallmarks of aging.  

 

Let’s talk about the mitochondrial free radical theory of aging. 

Mitochondria research has been such a strong topic of aging research that a prevailing theory resides in the scientific community: the mitochondrial free radical theory of aging. 

The theory proposes that the free radicals produced by your mitochondria are the culprits of mitochondrial dysfunction.  

During the process of turning your food into energy, your mitochondria produce unfortunate byproducts. Like a gasoline engine releasing carbon emission, your mitochondria emit free radicals.  

Free radicals are unstable molecules that can wreak havoc in your cells, damaging your DNA and other important cell functions. Typically, your body has enough antioxidants to combat these free radicals, achieving a balance in your system. However, there may be certain lifestyle factors that can place your mitochondria into overdrive. 

Poor diet, drinking, sleep disruption, overtraining, sun exposure are just a few ways your mitochondria undergo this imbalance between your free radicals and antioxidants, also known as oxidative stress. 

 

Your mitochondria have their own DNA. 

Unique to some of your other organelles, mitochondria have their own DNA known as mtDNA. 

The popular belief is that the mitochondria used to exist entirely separate from  cells, operating as single-celled organisms on their own.  

Sound familiar?  

Yes, they may have looked and behaved a lot like bacteria. But instead of attacking your cells, like some bacteria, they decided to live symbiotically. Without your mitochondria, we would have never become the complex organisms we are today.   

Adding more to their intrigue, mtDNA can only be passed down from mother to child, making you more genetically similar to your mother than your father. Popular ancestry DNA kits lean on mtDNA to make their deductions.  

 

MtDNA mutations may be a factor of aging. 

Traditionally, the causal link between DNA damage and aging has primarily looked at your DNA housed in the nucleus. MtDNA has now been a popular subject of aging research in the most recent years. Studies suggest aging is correlated to the damage caused by free radicals to your mtDNA as well.   

A review published in The Journal of Clinical Investigation states, 

“There is solid evidence that the amount of mtDNA mutations increases with age in humans; for example, deletions in mtDNA have been observed in the aged human central nervous system, skeletal muscle, and hepatocytes…In general, mutations of mtDNA may arise as a consequence of unrepaired DNA damage, for example, damage caused by ROS, or by replication errors during normal mtDNA synthesis.” 

Mutations to your mtDNA cause a proliferation of errors in the replication process, further disrupting your normal mitochondria function. And the less efficient your mitochondria become, a domino effect of issues occur to other cell functions that rely on mitochondrial energy. 

 

Your mitochondria are too close to the problem. 

Free radicals created by mitochondria are linked to all sorts of problems in the cell, and you can find them to be a culprit amongst the other hallmarks of aging. However, since your mitochondria are the primary source of free radicals, they may be getting the brunt of the damage. 

A review published in Cell argues that the mitochondria’s proximity to the problem could be accelerating its own decline.  

The review states, 

“In postmitotic tissue such as brain, the levels of oxo8dG are significantly higher in mitochondrial compared to nuclear DNA. Reasons for these differences are thought to include the proximity of mitochondrial DNA to the source of oxidants and the lack of any protective histone covering.”  

The free radicals produced from your mitochondria can create an immediate vicious cycle. Like a factory that poisons nearby villages with toxic runoff, the problem meets full circle when you realize the factory workers live in the nearby villages.  

 

Your mitochondria count changes with age. 

Mitochondria is the plural form of a mitochondrion. But hardly anyone refers to mitochondria in their singular form. Why? Because your cells, depending on their location, may have thousands of them in just one cell.  

For example, energy-demanding organs like the heart require loads of energy, primarily fueled by these tiny powerhouses. According to the British Society for Cell Biology, 40% of the cytoplasmic space in heart cells consist of mitochondria.  

Your mitochondria find their strength in numbers. The more mitochondria we have, the less burden one mitochondrion has to sustain your energy.  

However, researchers from the School of Kinesiology and Health Scientists at York University show we make fewer mitochondria as we age.   

A lower mitochondria count can overload the system, burdening your tiny powerhouses with the same energy demand but with fewer hands to divide the work.  

 

You need to stay active as you age. 

A comparative study published in the Journal of Gerontology shows that exercise can help promote mitochondrial biogenesis, a process where your body creates more mitochondria. 

Your mitochondria are very responsive organelles. If they detect an increase in energy demand, they can replicate themselves to provide more help for the new workload.  

However, the inverse is also true. If you have a more sedentary lifestyle, your mitochondria see that your day-to-day energy needs are minimal. And supporting multiple mitochondria is an expensive process. In response, your mitochondria will reduce their numbers to maintain efficiency.  

It's important to incorporate an active lifestyle, especially as you age, so that your mitochondria know to supply ample amounts of energy. In turn, your mitochondria will multiply and help stave off mitochondrial dysfunction. 

 

NAD+ boosting supplements can help. 

The unsung heroes of your mitochondria are their collaborators, NAD+ (nicotinamide adenine dinucleotide).  

NAD+ are tiny helper molecules that essentially keep the wheels turning within the engines of the mitochondria. Without them, the mitochondria would sit dormant. 

Studies suggest that increasing NAD+ can support mitochondrial function. A preclinical study published in EMBO Molecular Medicine shows supplementation with nicotinamide riboside (NR), a novel form of vitamin B3 that increases NAD+, resulted in mitochondrial biogenesis in mice. 

 

You don’t have to “feel” old if you take care of your mitochondria. 

If “feeling old” was tied to our propensity for fatigue, mitochondrial dysfunction could be the cause. 

An article published in Integrative Medicine highlights that the loss of function in your mitochondria can result in excess fatigue, a common symptom of aging. And supporting your mitochondria may be one of the best ways to fight it.  

Health advocates may focus their attention on big-picture health advice, like participating in routine exercise and maintaining a healthy diet. But you might not realize that these steady steps are actually making real molecular changes in your body. And taking care of your mitochondria is just one of the numerous ways that can help you improve the way you age. 

Mitochondria are a vital part of all cells in our body. They provide power for the functions that keep us alive and healthy, such as breathing, digesting food, and thinking. But they also have many other jobs apart from being just energy generators. Their duties range from protection against diseases to playing an essential role in the aging process.

As a result, if there is a decrease in the function of mitochondria in your cells, the rest of your body can be affected. This reduction in functionality is known as mitochondrial dysfunction, and it can impact your health in several important ways. 

Let’s talk about mitochondrial dysfunction, how it affects your health, and what supportive measures you can take to optimize the health of these important organelles.

 

What are mitochondria and what do they do?

Mitochondria are the energy-producers found in almost all of your cells. They create energy from the food you eat to make adenosine triphosphate (ATP). ATP is the energy-carrying compound used by cells to fuel your body's functions.

According to a review published in Molecular Cell, mitochondria also play a role in supporting your immune system and cellular signaling when the body is under stress. 

Mitochondria come in a variety of shapes and sizes, depending on where they are found. A review published in EMBO Reports explains that the shape of mitochondria influences their function. 

This is especially important to note because, as illustrated in International Journal of Molecular Sciences, mitochondrial shape and functionality appear to be very sensitive to environmental exposures like pesticides. In other words, exposure to toxins, even commonly used pesticides, may impact your mitochondrial health and increase your risk of developing certain chronic health conditions.

 

What is mitochondrial dysfunction?

Mitochondrial dysfunction occurs when your mitochondria lose the ability to function normally. It can happen if the mitochondria present in your cells are not functioning as they should. 

 

What is the relationship between mitochondria and free radicals?

When mitochondria make ATP, they also generate free radicals, which are molecules that can cause damage to proteins and DNA in your body. Ideally, free radicals are balanced in the body by antioxidants that help make them less dangerous.

Free radicals are also produced in response to different environmental factors such as exposure to toxins and inflammation, but mitochondria are the primary producers in your body. At the same time, mitochondria help clean up free radicals, so it's a delicate balance between the two.

When mitochondria are dysfunctional, they no longer produce ATP efficiently while increasing their production of free radicals, throwing off that balance.

According to the review article published in npj Regenerative Medicine, if mitochondria are damaged, not only is energy metabolism affected, but they can also produce more free radicals increasing the potential for oxidative damage in the body.

As described in Cell Death and Disease, mitochondrial dysfunction can also influence antioxidant activity in the cell, and the entire cell can be damaged or destroyed. Essentially the entire health of your cell can be affected as a result of improperly functioning mitochondria. 

 

What causes mitochondrial dysfunction?

In a healthy state, mitochondrial numbers are balanced by creating new functional mitochondria (mitochondrial biogenesis) and removing any that are damaged or dysfunctional (mitophagy). But this process can be negatively impacted by many reasons. 

Damage to mitochondria from free radicals and other environmental factors like toxins or inflammation may lead to mitochondrial dysfunction as the cells become overwhelmed with free radical production.  

Additionally, if there is inadequate availability of nutrients such as B vitamins, mitochondria will not produce the energy they need.

Several health conditions may also result in mitochondrial dysfunction because their mechanisms can lead to oxidative stress or inflammation that affects mitochondrial function.

The result? As described in the journal Biology, the presence or accumulation of dysfunctional mitochondria can increase and eventually contribute to accelerated aging and adverse health outcomes.

 

How does mitochondrial dysfunction influence aging?

While mitochondrial dysfunction can result from your environment, research from The Journals of Gerontology suggests that the function and number of mitochondria also naturally decline as we age. Older mitochondria can also change shape, generate more free radicals, and become less efficient at producing ATP.

However, it may be a vicious cycle. Increases in inflammation and reduced antioxidant activity also naturally increase as you age. These changes increase free radical production and affect the health of mitochondria. 

And once again, as described in a review from the journal Cell, poorly functioning mitochondria can increase the production of free radicals, which only makes mitochondrial dysfunction worse. 

As noted in The Journal of Signal Transduction, these factors add up to influence the aging process and age-related health conditions.

 

Chronic health conditions and mitochondrial dysfunction

Mitochondria are also closely connected to several health conditions usually associated with aging. It's well accepted that inflammation and oxidative stress are related to poor health. As written in Endocrine Reviews, mitochondrial health may also be an important piece of the puzzle.

Several of the adverse outcomes associated with mitochondrial dysfunction include:

• Cognitive and neurodegenerative conditions. Conditions related to brain health are often considered diseases of aging. A review from BBA - Molecular Basis for Disease suggests that defects in the way the mitochondria processes ATP, an increase in free radical generation, and the production of specific proteins that stress the mitochondria have all been associated with certain conditions affecting the brain.

• Blood sugar balance. As illustrated in Antioxidant and Redox Signaling, people with conditions impacting blood sugar balance may also have dysfunctional mitochondria with irregular shapes. However, researchers aren't clear if these changes cause blood sugar imbalances or are a result.

• Fatigue. Unexplained, unrelenting fatigue is also a hallmark of mitochondrial dysfunction. A review from Metabolic Brain Disease suggests that people who suffer from debilitating fatigue associated with certain health conditions may have dysfunctional mitochondria.

• Signs of aging. Even the aging process seen in the skin may have a relationship to mitochondrial defects. A review published in Cell Death and Disease found that aging skin is associated with damaged mitochondria, high amounts of free radicals, and oxidative stress.

As a result, supporting the health of your mitochondria may offer protection against age-related conditions.

 

What can you do to keep your mitochondria healthy?

While you can't stop time, you can support your mitochondria with these healthy habits: 

• Intermittent fasting. As seen in a study published in PLOS One, intermittent fasting may support improvements in mitochondrial health by reducing the impact of environmental influences like a high-fat diet. Fasting may support the critical balance between mitophagy and mitochondrial biogenesis, helping remove dysfunctional mitochondria while increasing the number of healthy functioning mitochondria.

• Exercise. According to a symposium review published in The Journal of Physiology, physical activity supports healthy mitochondria not just in muscle cells but throughout the body. This review suggests that both endurance activity, as well as high-intensity training, can be beneficial.

• Diet. As explained in a review published in Clinical Nutrition, a healthy diet rich in micronutrients is vital to support healthy energy metabolism and mitochondrial health. Additionally, certain inflammatory foods such as trans fats or heavily processed items can contribute to inflammation in the body and increase free radical production. 

• Mitochondrial supplements. Several supplements have valid research behind their use for supporting your mitochondria, especially relating to the relationship between mitochondrial health and fatigue. These include CoQ10, alpha-lipoic acid, and NAD precursors.

 

Protecting your mitochondria is an investment in your health

Mitochondrial dysfunction happens when the function of mitochondria is reduced. It is associated with accelerated aging and certain chronic health conditions. It's important to note that mitochondrial dysfunction is different from genetic mitochondrial diseases, which are inherited disorders. 

You can support mitochondrial health through lifestyle habits that provide an optimal cellular environment. Reducing the impact of free radical damage and inflammation while increasing the generation of new mitochondria is critical for an optimal balance. Taking steps to keep your mitochondria healthy and happy is beneficial regardless of your age—it's never too early or too late to get started.