Although Americans have been picking on natto beans for 150 years(?), recently many positive articles began to show up--including the following.
"Japanese researchers found a statistically significant inverse correlation between the incidence of hip fractures in women and natto consumption. In other words, the more natto consumed, the lower the incidence of hip fracture. Feeding ovariectomized rats natto has also been shown to have a preventive effect on bone loss."