CLINICAL NUTRITION ASSESSMENT OF ISS ASTRONAUTS (CLINICAL NUTRITION ASSESSMENT)
Research Area: Human Research: Integrated Physiology and Nutrition
Expedition(s): 1-14
Principal Investigator(s): ● Scott M. Smith, PhD, NASA’s Johnson Space Center, Houston,
Texas
RESEARCH OBJECTIVES
Nutritional assessments of astronauts before, during, and after spaceflight ensure adequate
intake of energy, protein, and vitamins during missions. Scientists use the information to
understand the connections between nutrition and human health during spaceflight, and to
develop effective dietary strategies to reduce adverse health impacts.
EARTH BENEFITS
Increased understanding of the connections between nutrition and bone loss has potential
value for patients suffering bone loss on Earth.
SPACE BENEFITS
Nutritional monitoring is vital to ensuring crew health during long-duration spaceflight. The
results are being used to identify specific effects of microgravity on nutrient-dependent
processes such as vitamin uptake, antioxidant production, and metabolism of iron. Alterations
to nutrient assimilation in microgravity are also important for studies of bone loss while in
microgravity.
RESULTS
Results have been compiled and analyzed for International Space
Station (ISS) crew members. Intake of energy (relative to World
Health Organization standards) was observed to generally decrease
over time during missions. However, when dietary counseling was
provided to a single astronaut during flight, adequate energy intake
was maintained throughout the mission. Body weight, total bone
mineral content, and bone mineral density decreased during flight.
Antioxidant capacity decreased during flight, leading to increased
susceptibility to genetic damage from radiation. Vitamin D
concentration in crew bone was decreased, and bone resorption
increased, by long exposure to microgravity. The relative
concentrations of other blood and urine analytes preflight and
postflight were variable and subject to several confounding
factors that limit conclusions as to particular effects of spaceflight
(Smith, 2005, 2008). The results of this study formed the basis for
the nutrition and repository experiments, currently being
operated on the ISS.
ISS012E12635 – International Space
Station Science Officer Bill McArthur
during expedition 12, during check-out
of the SLAMMD hardware of HRF-2.
Measuring the mass of a crew
member in space is difficult because
mass does not equal weight in the
absence of gravity. NASA image.