The NASA Twins Study Science teams published their final stages of integrated research in the journal Science 12 April 2019. This video provides a short summary. More extensive details from each of the ten studies are explained in this article from NASA.
The Twins Study
How does an extended mission in space lasting as long as a year affect the human body? To answer that question, NASA used astronaut twins Mike Kelly and Scott Kelly as subjects. Scott spent 340 days aboard the Space Station from 27 March 2015 to 1 March 2016. Mike remained on Earth. Each was tested in a variety of ways by the research teams in order to compare results of long duration space flight.
Scott Kelly wrote the book Endurance about his experience. It is an excellent account of the lives of Mark and Scott, how they became astronauts, and behind the scenes events in the space program.
Ten research teams investigated a wide variety of factors shared by the twins. Their unique genetic similarity made them ideal candidates to see what environment does to the human body. The teams conducted individual studies in 2015-16. Results were integrated between teams in 2017. Preliminary findings were presented in the spring of 2018. My previous posts are linked here.
Application of Results
The human body is resilient and robust and can adapt to changes induced by the spaceflight environment. Inflight changes returned to preflight levels by the study’s end including immune responses, epigenetic changes, gut bacteria, body weight, and serum metabolites. After landing, inflammation and immune response factors were affected. A few factors remained altered at the conclusion of the study. A small subset of changes remained after the study concluded such as gene expression, telomere dynamics, DNA disruption, carotid artery thickening, ocular changes, and some cognitive functions.
This may lead to new treatments and preventative measures for stress-related health risks on Earth. For example, telomere research may impact research on aging and disease. The proteomic research might improve treatment of traumatic brain injury. Insights may be gained into how body changes are related to risk factors for diseases. Spaceflight research can help humankind.
NASA rigorously trains astronauts for their missions, plans their lifestyle and work regimen while in space, and rehabilitates and reconditions them when they return to Earth.
Thanks to these measures and the astronauts who tenaciously accomplish them, the human body remains robust and resilient even after spending a year in space. Research from the landmark Twins Study may guide NASA’s Human Research Program studies for years to come, as NASA continues to prioritize the health and safety of astronauts on spaceflight missions, particularly long-duration missions on the International Space Station, and to the Moon, Mars, and worlds beyond.