Can mitochondria slow aging? Separating science from marketing claims

To understand the full picture, it is first necessary to understand what mitochondria actually are. Mitochondria can be thought of as the “power plants” of the body’s cells. They convert energy from food into usable energy that the body can use. Thanks to this energy, muscles can contract, the brain can function and the body can perform every activity — from walking and breathing to physical exercise.

However, it is now known that their role is much broader. Mitochondria are involved in regulating metabolism and calcium levels within cells, communication between different parts of the cell, cellular defense mechanisms against oxidative damage, regulation of inflammation, programmed cell death, responses of the innate immune system and more. All of these functions make mitochondria an essential part of the proper functioning of the entire body.

When asked whether mitochondrial function declines with age, the simple answer is yes, but the relationship is not straightforward. Studies show that as people grow older, they may experience a decline in energy production capacity, reduced activity of mitochondrial enzymes, weakened mitochondrial quality-control mechanisms and accumulation of damaged mitochondria in some tissues.

However, not all of these changes are caused by chronological aging itself. Factors such as reduced physical activity, obesity, loss of muscle mass and chronic diseases affect mitochondrial function, sometimes more than age itself.

Changes in mitochondrial function may appear as slower recovery after exertion, reduced muscle performance and sometimes an increased risk of disease. However, not every older person experiences significant mitochondrial impairment and not every decline in function is caused solely by aging. Studies examining active older adults have found that much of mitochondrial capacity can be preserved even later in life through an active lifestyle and appropriate nutrition.

Renewed interest in mitochondria stems from a combination of three factors: Over the past two decades, there has been significant progress in understanding cellular processes related to aging and mitochondria have been identified as one of the hallmarks of aging, alongside other processes.

Once research began pointing to the importance of mitochondria, products and dietary supplements promising to “activate,” “strengthen” or “renew” them also appeared. Most of these supplements are based on promising biological mechanisms, but as of today, none has been proven in high-quality human clinical studies to extend lifespan or significantly improve the healthy lifespan of healthy people.

From a scientific perspective, even the attempt to “strengthen mitochondria” is not entirely accurate, since mitochondria are not a muscle that can simply be strengthened. Researchers today focus on concepts such as mitochondrial biogenesis — the creation of new mitochondria; mitophagy — the removal of damaged mitochondria; mitochondrial dynamics — the processes of fusion and division; and mitochondrial quality control. The goal of these processes is not to “recharge” mitochondria, but rather to maintain a population of high-quality, functional mitochondria.

There is no doubt that mitochondria play a central role in human health. However, as of today, there is no conclusive evidence that taking one supplement or another on its own will lead to a significant extension of lifespan or a dramatic improvement in health. In addition, many researchers emphasize that the human body is not a system with a single switch that can simply be turned on or repaired. Human health is the result of a complex interaction between many systems working together. Therefore, it is extremely difficult to isolate mitochondria from all other components of life and health.

When researchers and health professionals are asked what truly helps maintain proper mitochondrial function, their answers repeatedly return to the same basic principles: physical activity is the intervention with the strongest evidence for improving mitochondrial function.

Endurance training, strength training and interval training all promote mitochondrial adaptations, although each does so through slightly different pathways. Skeletal muscle is the tissue richest in mitochondria in the body, which is why maintaining muscle through resistance training and adequate protein intake also contributes to metabolic health.

In the field of nutrition, there is currently no single diet that has consistently been proven superior for improving mitochondrial function. However, there is broad support for consuming sufficient protein, maintaining a healthy body weight, following a diet based primarily on whole and minimally processed foods, consuming adequate vitamins and minerals and drinking according to the body’s needs.

Chronic stress affects the nervous system, sleep quality, behavior and metabolism. Its impact on mitochondria is likely mediated through a range of mechanisms rather than a single pathway.

When it comes to dietary supplements, it is especially important to distinguish between a promising biological mechanism and a meaningful clinical outcome. In some populations — such as people with heart failure, certain mitochondrial diseases or those taking statins — there is stronger evidence for the benefits of some supplements. However, these findings do not necessarily justify broad recommendations for the general population.

One of the main challenges in this field is the gap between scientific research and the way it is presented to the public. Science usually advances through small, cautious and controlled steps. Marketing, on the other hand, favors big promises, quick solutions and appealing headlines.

As a result, it can sometimes create the impression that there is a “secret” or “hidden mechanism” that, if only we knew how to activate it, could stop aging. The reality, at least for now, does not support this idea.

It is important to remember that a biological mechanism is not clinical proof, improvement in a laboratory measurement does not necessarily mean improved health, results in animals do not necessarily apply to humans and a single clinical study is not enough to change recommendations.

Therefore, when evaluating claims about a “life-extending supplement,” it is worth asking: Was the research conducted in humans? Was it a randomized controlled trial? Is there a systematic review or meta-analysis confirming the findings? And were meaningful clinical outcomes measured that demonstrate improved health, rather than only changes in biological markers?

Mitochondria are undoubtedly a central component of the body’s function and of our understanding of aging processes. Research in this field is fascinating and is expected to continue developing in the coming years. However, as of today, there is no proven shortcut that can replace the basic principles of health.

As research advances, it becomes increasingly clear that the foundation of good health does not rest on a single supplement or a single mechanism, but on a consistent combination of healthy lifestyle habits. And in this case as well, mitochondria are an important part of the story — but they are far from being the whole story.

The authors are Dr. Etay Ziv, an expert in physical activity, sports and healthy lifestyle and a lecturer at the Levinsky-Wingate Academic Center; and Nir Fink, a sports dietitian, exercise physiologist and lecturer in sports nutrition and exercise physiology.