Isoflavone-Rich Soy Yogurt Benefits Bones

SAO PAULO, BrazilIngestion of isoflavone-enriched soy yogurt helped maintain bone density in ovariectomized (Ovx) rats, according to a new study (J Maturitas, ePub March 27, 2007; DOI:10.1016/j.maturitas.2007.01.011). Researchers from Sao Paulo State University and the Federal University of Sao Carlos divided rats into seven-member groups: two control sedentary groups, Ovx or sham-Ovx; three Ovx given soy yogurt and no exercise, soy yogurt plus resistance exercise, or just exercise; and three sham-Ovx given soy yogurt and no exercise, soy yogurt plus resistance exercise, or just exercise. The animals receiving the soy yogurt, which included isoflavones at 50 mg/100 g of product, received 3 mL/kg body weight/d. After 12 weeks, the animals were sacrificed and bone mineral density (BMD) and alkaline phosphatase (AP) activity determined.

All treated animals showed significant increases in femur and tibia BMD values and in serum AP activity, compared to the control group. The researchers concluded ingestion of soy yogurt with isoflavones could prevent bone mass loss in Ovx rats and increase bone mass in sham rats; resistance exercise was also effective in augmenting bone mass in sham and Ovx rats.