Omega-3 is one of the stars of the nutrition industry, with the ingredients market valued at a whopping $1.6 billion by Frost & Sullivan. The fatty acids, most notably EPA and DHA (docosahexaenoic acid), have been linked to a wide-range of health benefits, including reduced risk of cardiovascular disease (CVD) and certain cancers, good development of a baby during pregnancy, joint health, and improved behaviour and mood.
Sky may not be the limit
According to findings published in the Journal of Bone and Mineral Research, new research from NASA suggests that EPA may protect against bone loss during space flight.
Led by Dr Sara Zwart from the Universities Space Research Association in Houston the researchers looked at levels of a protein called NF-kappaB that is linked to a range of functions, including bone resorption, muscle wastage, and immune health. Data showed that NF-kappaB levels were higher in astronauts following periods of spaceflight. However, astronauts who reported higher intakes of fish, and therefore the omega-3s they contain, had lower levels of bone loss after spaceflight.
These observations were supported by cell studies, said the researchers, which showed that EPA decreased the activation of NF-kappaB.
To boldly go where no PUFA has gone before
“We now have evidence that NF-kappaB is activated after short-duration spaceflight, and therefore inhibition of NF-kappaB activation could have many beneficial downstream effects to counteract the negative effects of spaceflight on bone, muscle, and immune function,” wrote the researchers.
“Beyond muscle, bone, and immune function, the role of n-3 fatty acids in cancer prevention is currently being investigated in animal models of spaceflight radiation effects, with positive results.
“Thus, there is a good possibility that something as simple as a menu change to increase fish intake might serve as a countermeasure to help mitigate risks related to bone, muscle, immune function, and potentially even radiation,” they added.
Dr Zwart and her co-workers measured the expression of the gene that codes for NF-kappaB before and after 12-16 days on a Shuttle for 7 males and 3 females astronauts. Data showed that NF-kappaB levels increased by almost 500 per cent following short-term spaceflight.
Additional data from astronauts on longer spaceflights and stays on the Russian Mir space station were also studied. Their dietary intakes were assessed using food frequency questionnaires, and they underwent bone exams. Increased fish intakes were associated with reduced bone loss during weightlessness, said the researchers.
Similar results were observed for people with extended periods of bed-rest, they added.
To infinity and beyond
Dr Zwart and her co-workers called to intervention studies with dietary sources of omega-3 fatty acids to elucidate the mechanism behind the apparent bone benefits, as well as to study effects of muscle and antioxidant defences.
“These data will have significant implications for future space exploration, and could benefit the general population,” they concluded.
Source: Journal of Bone and Mineral Research
Published online ahead of print, doi: 10.1359/JBMR091041
“Capacity of Omega-3 Fatty Acids or Eicosapentaenoic Acid to Counteract Weightlessness-Induced Bone Loss by Inhibiting NF-κB Activation: From Cells to Bed Rest to Astronauts”
Authors: S.R. Zwart, D. Pierson, S. Mehta, S. Gonda, S.M. Smith