In orbit the human body ages at drammatic speed. Several studies have shown that the absence of gravity and the prolonged permanence in space generate a process which is similar to Earth-based aging but occurs at much higher speed. For example, an astronaut during a 6 months space mission loses the same amount of bone tissue as a person on Earth between the 10 years going from the age of 50 to 60!

Nevertheless the competencies and technologies used by space doctors allow astronauts to fly in space for very long periods and come back home healthy.

Our clinical research carried out at the European Space Agency (ESA), NASA and Russian Space Agency focused on the effects of long term space missions on astronauts and on countermeasures to avoid them:

- Loss of bone tissue
- Metabolic and hormonal dysfunction including insulin-resistance and hypothyroidism
- Physical and psychological adaptation difficulties
- Fatigue and stress
- Reduced levels of energy
- Loss of muscle strength and mass
- Loss of postural, proprioceptive and coordination capabilities
- Decreased cardiovascular performance
- Accumulation of toxins and free radicals
- Decreased immune response to infections
- Allergies, auto-immune diseases and chronic inflammation
- Exercise intolerance, back pain
- Digestive problems
- Lack of nutrients, dysbiosis and GI problems
- Dysregulation of cellular membranes (signals, receptors, etc)
- Depression, anxiety, aggressiveness, frustration

All these phenomena that occur in astronauts in a matter of months, are overlapping with what happens to all of us on Earth in some decades.