The DOI matches its Crossref record; 47 of the 51 references it cites were found in a registry or an index.
The Nutritional Status of Astronauts Is Altered after Long-Term Space Flight Aboard the International Space Station
Open accessAbstract
Defining optimal nutrient requirements is critical for ensuring crew health during long-duration space exploration missions. Data pertaining to such nutrient requirements are extremely limited. The primary goal of this study was to better understand nutritional changes that occur during long-duration space flight. We examined body composition, bone metabolism, hematology, general blood chemistry, and blood levels of selected vitamins and minerals in 11 astronauts before and after long-duration (128-195 d) space flight aboard the International Space Station. Dietary intake and limited biochemical measures were assessed during flight. Crew members consumed a mean of 80% of their recommended energy intake, and on landing day their body weight was less (P = 0.051) than before flight. Hematocrit, serum iron, ferritin saturation, and transferrin were decreased and serum ferritin was increased after flight (P < 0.05). The finding that other acute-phase proteins were unchanged after flight suggests that the changes in iron metabolism are not likely to be solely a result of an inflammatory response. Urinary 8-hydroxy-2'-deoxyguanosine concentration was greater and RBC superoxide dismutase was less after flight (P < 0.05), indicating increased oxidative damage. Despite vitamin D supplement use during flight, serum 25-hydroxycholecalciferol was decreased after flight (P < 0.01). Bone resorption was increased after flight, as indicated by several markers. Bone formation, assessed by several markers, did not consistently rise 1 d after landing. These data provide evidence that bone loss, compromised vitamin D status, and oxidative damage are among critical nutritional concerns for long-duration space travelers.
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“Astronauts had a decrease in 1,25 vitamin D levels (the active form of vitamin D) (Fig. 5B) consistent with other studies (Smith et al., 2005)”
From Comprehensive Multi-omics Analysis Reveals Mitochondrial Stress as a Central Biological Hub for Spaceflight Impact (2020) · cites this paper as Smith et al., 2005
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“In addition, there is a significant difference of serum level retinol between pre- and post-flight samples but not during flight. Serum retinol decreased from 0.73 ± 0.17 to 0.59 ± 0.13 µg/mL on landings occurred in Russia and increased from 0.52 ± 0.09 to 0.63 ± 0.12 µg/mL on landings in the US48,142.”
From Key points for the development of antioxidant cocktails to prevent cellular stress and damage caused by reactive oxygen species (ROS) during manned space missions (2021) · cites this paper as [48]
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“Initial findings from the Clinical Nutritional Assessment protocol identified evidence of vitamin D deficiency, altered folate status, loss of body mass, increased kidney stone risk, and more69,70.”
From Red risks for a journey to the red planet: The highest priority human health risks for a mission to Mars (2020) · cites this paper as [69]
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“astronauts from the ISS expeditions 1–8 were tested for oxidative stress upon landing, and researchers found that urine concentration of 8-hydroxy-2′-deoxyguanosine (8OHdG) was elevated by 32% upon landing on Earth, despite no evidence of lipid peroxidation”
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“Additionally, astronauts were also tested for red blood count SOD that was found to be reduced, thus suggesting a decreased antioxidant capacity48.”
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“However, the study of markers of ROS damage have been done with research purposes, observing an increase in astronauts48,50–52.”
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1 retracted
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Calcium Absorption Varies within the Reference Range for Serum 25-Hydroxyvitamin D
Heaney, R. P., Dowell, M. S., Hale, C. A., & Bendich, A. (2003) · Journal of the American College of Nutrition · doi:10.1080/07315724.2003.10719287 · Cited by 970
Prostate cancer risk and prediagnostic serum 25-hydroxyvitamin D levels (Finland)
Ahonen, M. H., Tenkanen, L., Teppo, L., Hakama, M., & Tuohimaa, P. (2000) · Cancer Causes & Control · doi:10.1023/a:1008923802001 · Cited by 494
Resistance exercise as a countermeasure to disuse-induced bone loss
Shackelford, L. C., LeBlanc, A. D., Driscoll, T. B., Evans, H. J., Rianon, N. J., Smith, S. M., Spector, E., Feeback, D. L., & Lai, D. (2004) · Journal of Applied Physiology · doi:10.1152/japplphysiol.00741.2003 · Cited by 392
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Items 301–314 of 314
Metabolic and endocrine changes in spaceflight
O’Leary, K. S., Güner, Z., Mathyk, B. A., & Erenler, F. (2025) · Elsevier eBooks · doi:10.1016/b978-0-443-32904-3.00017-0
Dickerson, B. L., Sowinski, R. J., & Gonzalez, D. E. (2026) · Life · doi:10.3390/life16020258
Gomes, L. R., Magalhães, I., & Silva, M.-R. G. (2026) · Athena health & research journal. · doi:10.62741/ahrj.v3isuppl.97
Szatmári, P., Meier, O., Fári, M., Meszter, R., Tóth, C., Koroknai, J., Makleit, P., Domokos-Szabolcsy, É., & Veres, S. (2026) · Kertgazdaság · doi:10.56617/hc.7657
Microgravity-Induced Gut Dysbiosis and its Consequences for Brain Health
Sappa, S., Keremane, P., & Mumbrekar, K. D. (2026) · Microgravity Science and Technology · doi:10.1007/s12217-026-10269-w
St‐Martin, P., Dougkas, A., Roux, E. L., Ritsch, N., Bourdier, P., Breit, M. J., Chery, I., Zahariev, A., Oustric, P., Berghe, L. V. D., et al. (2026) · Research Square · doi:10.21203/rs.3.rs-10461935/v1
Antioxidant Countermeasures for Oxidative Stress in Spaceflight and Terrestrial Environments
Suleiman, Z., Oko, O., Ademu, A., Mariya, A., Eneh, N. W., Usman, M., Abu, E., Shuaibu, M., & Ezeh, I. (2026) · American Journal of Life Sciences · doi:10.11648/j.ajls.20261404.11
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Dickerson, B. L., Gonzalez, D. E., Comfort, P., Hardy, J. G., Hines, K., Anderson, D. N., Macaulay, T. R., Stankovic, A. S., & Twine, C. (2026) · Frontiers in Physiology · doi:10.3389/fphys.2026.1950155
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Lenarczyk, M., Kronenberg, A., Kwok, A., Borg, A. M., Alsheikh, A. J., Mathison, A., Zimmermann, M. T., Lawton, S. B., Raff, H., Willey, J. S., et al. (2026) · PLoS ONE · doi:10.1371/journal.pone.0357485
Bone Loss in Space Flight and Countermeasures
LeBlanc, A., Spector, E. R., & Schneider, V. S. (2012) · Springer eBooks · doi:10.1007/978-1-4471-2745-1_13
Metadata
- Authors
- Smith, S. M., Zwart, S. R., Block, G., Rice, B. L., & Davis-Street, J. E.
- Affiliations
- National Aeronautics and Space Administration (US)
- University of California, Berkeley (US)
- Corresponding author
- Smith, Scott M.
- Venue
- The Journal of Nutrition
- Publisher
- Elsevier BV
- Published
- 2005-03
- Volume
- 135
- Issue
- 3
- Pages
- 437-443
- ISSN
- 0022-3166 (ISSN-L)
- OpenAlex
- W1891721997
- Cited by
- 316
- References
- 51
- Citations by year
- 2026: 14 · 2025: 26 · 2024: 19 · 2023: 19 · 2022: 23 · 2021: 19 · 2020: 20 · 2019: 17 · 2018: 10 · 2017: 13 · 2016: 13 · 2015: 10 · 2014: 18 · 2013: 15 · 2012: 15
- FWCI
- 7.34
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Licence
- Locations
- Journal of Nutrition (publishedVersion)
- PubMed (publishedVersion)
- Funders
- Johnson Space Center
- Topics
- Health Sciences › Medicine › Physiology (medical) › Spaceflight effects on biology
- Physical Sciences › Engineering › Aerospace Engineering › Space Exploration and Technology
- Social Sciences › Political Science and International Relations › Space exploration and regulation
- Keywords
- astronaut nutrition, long-duration spaceflight, International Space Station, body composition, bone metabolism, bone resorption, bone formation markers, iron metabolism, serum ferritin, hematocrit, acute phase proteins, oxidative stress, 8-hydroxy-2'-deoxyguanosine, superoxide dismutase, vitamin D status, 25-hydroxyvitamin D3, vitamin D supplementation, energy intake, weight loss
- MeSH terms
- 8-Hydroxy-2'-Deoxyguanosine, Acute-Phase Proteins, Adult, Body Composition, Calcifediol, Energy Intake, Deoxyguanosine, Erythrocytes, Female, Humans, International Cooperation, Male, Middle Aged, Nutritional Status, Space Flight, Superoxide Dismutase, Time Factors, Vitamin D, Biomarkers, Oxidative Stress, Astronauts, Dietary Supplements
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