Osteoporosis is a major health issue in ageing populations. Therefore, it would be desirable if low bone mass leading to osteoporotic fractures could be prevented. A nutritional approach would be an inexpensive means to achieve this goal. So far we found 25/54 items with bone resorption inhibitory activity in the rat. Activity appears to be restricted to the categories vegetables, salads, herbs, mushrooms, fruits and red wine residue. To date we have identified 10 monoterpenes as active components of herbs rich in essential oils and a gamma glutamyl peptide as active agent (in vitro) from onion. Two items were also studied as to their effect on bone "mass". Both improved trabecular bone mineral density. Furthermore, 6.2 g of fresh active items per kg body weight appears as the minimal inhibitory dose. Thus, in humans the amount of active items consumed by way of a regular Western diet with 2-3 servings/day of 80 g each of fruits and vegetables might be too low to elicit a protective effect. Whether 5 daily servings of the active items we have identified in rats are capable to inhibit bone resorption in humans must now be established with clinical intervention studies.