A daily supplement of 1,000 mg omega-3s in combination with aerobic exercise was associated with increases in bone mineral density (BMD) of up to 19% in post-menopausal women, according to findings published in Nutrition & Metabolism.
In addition, markers of inflammation such as interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-alpha) were significantly reduced following 24 weeks of supplementation plus exercise, report researchers from Urmia University in Iran and the University of Missouri in the US.
“These findings clearly show that the combination of PUFA supplementation with aerobic exercise provides numerous benefits on bone density and inflammation over exercise alone or supplementation alone,” they wrote.
Bone health
The study’s findings have implications for the increasing number of women at risk of osteoporosis, characterized by low bone mass, which leads to an increase risk of fractures, especially the hips, spine and wrists. An estimated 75 million people suffer from osteoporosis in Europe, the USA and Japan.
Women are four times more likely to develop osteoporosis than men.
Study details
The new study sought to investigate the effects of long-term omega-3 supplementation (Viva Omega-3 fish oil by Canada’s Viva Pharmaceutical) and aerobic exercise on BMD, bone biomarkers, and inflammatory markers in post-menopausal women.
Seventy-nine healthy post-menopausal women were recruited and randomly assigned to one of four groups: The first group acted as the control and did not receive supplements or an exercise plan; the second group received the exercise plan only; the third group received omega-3 supplements only (1,000 mg omega-3 per day, of which 180 mg was EPA and 120 mg was DHA); and the final group received both supplements and exercise.
The exercise plan involved walking and jogging three times a week at up to 65% of the maximum heart rate.
Twenty-four weeks later, and the researchers found that the combined omega-3-exercise group displayed BMD increases of 15% in the lower back and 19% in the neck of the thigh bone (femur) at the hip.
In addition, the combination group had decreased levels of the pro-inflammatory compounds IL-6 and TNF-alpha by 40% and 80%, respectively.
No increases in BMD or decrease in inflammatory markers were observed in the other three groups.
Linking inflammation and bone health
The researchers note that the decrease in inflammatory compounds correlated with the increase in BMD.
Commenting on the potential mechanism, they noted that inflammatory compounds play a “direct and an indirect role in the regulation of osteoclast and osteoblast activities”. Osteoblasts are cells responsible for bone formation and therefore strengthen the bone, whereas osteoclasts are cells that break down bone, and therefore weaken it.
“Therefore, a decrease in cytokine production may be beneficial to BMD,” they added.
“Further studies on the physiologic effects of omega-3s and exercise training on bone metabolism and bone quality to prevent or treat osteoporosis are needed,” concluded the researchers.
Source: Nutrition & Metabolism
2011, 8:71 doi:10.1186/1743-7075-8-71
“Long-term aerobic exercise and omega-3 supplementation modulate osteoporosis through inflammatory mechanisms in post-menopausal women: a randomized, repeated measures study”
Authors: B. Tartibian, B.H. Maleki, J. Kanaley, K. Sadeghi