Effects of tomato and broccoli on the bone status of growing female rats with different levels of calcium intake

Abstract

A total of 130 weanling female SD rats were allowed one week of adaptation before they were assigned into 13 treatment groups. The baseline group was killed at the beginning of the experiment. Groups A, B, C and D were fed the AIN93G diet containing 0.1% calcium; groups E, F, G and H were fed the AIN93G diet containing 0.25% calcium; and groups I, J, K and L were fed the AIN93G diet containing 0.5% calcium. Corn starch (20% of the diet) was replaced by tomato powder for groups B, F, and J; by broccoli powder for groups C, G and K; and by a 50:50 mixture of tomato and broccoli powders for groups D, H and L. The rats were fed the assigned diets for 8 weeks. Bone length, ash, calcium content and breaking strength became higher as dietary calcium concentration increased. Substitution of the corn starch by tomato and/or broccoli powders did not significantly affect the bone status of rats fed diets containing 0.25% or more of calcium. However, tomato and/or broccoli improved the bone status of rats fed diets containing 0.1% calcium. These results indicate that vegetables such as tomato and broccoli can have beneficial effects on bone when calcium intake is very low.