Oxidative stress: an invisible enemy
The core of the problem lies in plants' adaptation to the hostile space environment. Under the influence of microgravity and cosmic radiation, the biological systems of plants, including their defense mechanisms, undergo significant changes. In response to this environmental stress, plants produce an excess of ROS, highly unstable molecules that, while playing an important role in normal cellular signaling, become harmful when they accumulate in large quantities. This imbalance leads to what is known as "oxidative stress," a process that causes damage at the molecular and cellular levels. Ionizing radiation, in particular, can trigger the formation of ROS directly within plant cells, compromising their structure and function.

From space farm to human body: a chain of risks
Mokhtari's study challenges the assumption that space-grown plants are solely beneficial. The consumption of these ROS-laden plants introduces these damaging molecules directly into astronauts' bodies. The human body has natural systems to counteract ROS, but chronic and prolonged exposure to high levels can overwhelm these defenses. As the study highlights, the consequences are multiple and potentially serious.

Altered homeostasis: the accumulation of ROS can destabilize the body's biochemical balance, known as homeostasis. This imbalance can compromise essential cellular functions, from metabolic processes to DNA replication.

Impact on the gut microbiome: the gut microbiome, an ecosystem of bacteria crucial for digestion, the immune system, and mental health, is particularly vulnerable to oxidative stress. ROS can alter the composition and function of this delicate balance, leading to intestinal dysfunction and a greater susceptibility to diseases.

Cellular damage and degenerative diseases: the damage caused by ROS to DNA, proteins, and lipids is a known factor contributing to aging and the development of a wide range of chronic diseases, including cardiovascular and neurological disorders, and even some types of cancer. For astronauts, who are already exposed to a unique set of physiological stresses, the addition of this dietary risk represents a critical concern for their long-term health.

Mitigation strategies
Mokhtari's article does not just identify the problem but also emphasizes the urgency of developing innovative solutions. It is imperative that the safety of space-grown foods be re-evaluated. This could include:

Developing resilient plant varieties: selecting or engineering plants that are intrinsically more resistant to space-induced oxidative stress.

Advanced cultivation technologies: modifying growing conditions (e.g., light intensity and spectrum, nutrient composition) to minimize ROS production.

Dietary integration: supplementing astronauts' diets with antioxidants to counteract the excess ROS.

In conclusion, while space-based food autonomy remains a primary objective, Majid Mokhtari's study reminds us that every step forward brings new challenges. Food, once seen as the sole source of nourishment for space explorers, must now also be considered a potential source of risk. Addressing the ROS problem is fundamental to ensuring not only the sustainability of missions but also the long-term health and well-being of those who dare to venture beyond our planet's boundaries.

Bibliography

Mokhtari, M. (2025). "Space-driven ROS in cells: a hidden danger to astronaut health and food safety". Journal of Space Biology and Medicine, 15(2), 112-120.

Smith, J. A., & Chen, L. (2023). Oxidative Stress and Its Implications for Human Health. Academic Press.

NASA. (2024). Advanced Food Systems for Deep Space Missions: A Safety Protocol Review. NASA Technical Report.

*Board Member, SRSN (Roman Society of Natural Science)
Past Editor-in-Chief, Italian Journal of Dermosurgery