Mark Messina1,2, Pamela Magee3. 1. Soy Nutrition Institute, St.Louis, USA. markjohnmessina@gmail.com. 2. , 26 Spadina Parkway, Pittsfield, MA, 01201, USA. markjohnmessina@gmail.com. 3. Human Nutrition, Northern Ireland Centre for Food and Health (NICHE), University of Ulster, Coleraine, BT52 1SA, UK.
Abstract
INTRODUCTION: Despite the enormous amount of research that has been conducted on the role of soyfoods in the prevention and treatment of chronic disease, the mechanisms by which soy exerts its physiological effects are not fully understood. The clinical data show that neither soyfoods nor soy protein nor isoflavones affect circulating levels of reproductive hormones in men or women. However, some research suggests that soy protein, but not isoflavones, affects insulin-like growth factor I (IGF-1). METHODS: Since IGF-1 may have wide-ranging physiological effects, we sought to determine the effect of soy protein on IGF-1 and its major binding protein insulin-like growth factor-binding protein (IGFBP-3). Six clinical studies were identified that compared soy protein with a control protein, albeit only two studies measured IGFBP-3 in addition to IGF-1. RESULTS: Although the data are difficult to interpret because of the different experimental designs employed, there is some evidence that large amounts of soy protein (>25 g/day) modestly increase IGF-1 levels above levels observed with the control protein. CONCLUSION: The clinical data suggest that a decision to incorporate soy into the diet should not be based on its possible effects on IGF-1.
INTRODUCTION: Despite the enormous amount of research that has been conducted on the role of soyfoods in the prevention and treatment of chronic disease, the mechanisms by which soy exerts its physiological effects are not fully understood. The clinical data show that neither soyfoods nor soy protein nor isoflavones affect circulating levels of reproductive hormones in men or women. However, some research suggests that soy protein, but not isoflavones, affects insulin-like growth factor I (IGF-1). METHODS: Since IGF-1 may have wide-ranging physiological effects, we sought to determine the effect of soy protein on IGF-1 and its major binding protein insulin-like growth factor-binding protein (IGFBP-3). Six clinical studies were identified that compared soy protein with a control protein, albeit only two studies measured IGFBP-3 in addition to IGF-1. RESULTS: Although the data are difficult to interpret because of the different experimental designs employed, there is some evidence that large amounts of soy protein (>25 g/day) modestly increase IGF-1 levels above levels observed with the control protein. CONCLUSION: The clinical data suggest that a decision to incorporate soy into the diet should not be based on its possible effects on IGF-1.
Authors: Anna H Wu; Frank Z Stanczyk; Carmen Martinez; Chiu-Chen Tseng; Suzanne Hendrich; Patricia Murphy; Sukanya Chaikittisilpa; Daniel O Stram; Malcolm C Pike Journal: Am J Clin Nutr Date: 2005-05 Impact factor: 7.045
Authors: Peter H Gann; Ralph Kazer; Robert Chatterton; Susan Gapstur; Kim Thedford; Irene Helenowski; Sue Giovanazzi; Linda Van Horn Journal: Int J Cancer Date: 2005-08-20 Impact factor: 7.396
Authors: Jane Teas; Mohammad R Irhimeh; Susan Druker; Thomas G Hurley; James R Hébert; Todd M Savarese; Mindy S Kurzer Journal: Nutr Cancer Date: 2011-06-28 Impact factor: 2.900