FLAXSEED AND BONE METABOLISM: A REVIEW OF IN VIVO EVIDENCE AND POTENTIAL MECHANISMS OF ACTION

Wendy E. Ward, Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto , Ontario, Canada

Abstract: Osteoporosis is a serious public health problem, and strategies are needed to prevent and/or treat this disease. Flaxseed consumption is increasing in North American, and whether the consumption of flaxseed provides a novel dietary strategy for preventing or managing osteoporosis is an active area of study. To date, studies using rodent models suggest that consumption of flaxseed, secoisolariciresinol diglycoside (SDG) or flaxseed oil, at a level attainable by diet alone, from early life continuously throughout the life cycle is safe, with no adverse effects on developing bone. Moreover, these studies in developing animal models suggest that the greatest effects are observed when bone health is challenged by a disease condition. Positive associations between urinary enterolactone and bone mineral density (BMD) at the hip and spine, as well as data showing reductions in markers of osteoclastic activity associated with high levels of alpha-linolenic acid (ALA) from flaxseed, suggest that flaxseed may be useful to attenuate the deterioration of bone tissue during aging. Studies in men and women with low BMD are needed to confirm the benefits of flaxseed to maintaining bone health. Moreover, elucidating the active component(s) that affect bone tissue is needed to identify mechanisms of action.