The composition for treating bone loss is an alcoholic extract of Lavandula atriplicifolia plant flowers and leaves. The composition is prepared by extracting dried Lavandula plant flower and leaf powder in ethanol or methanol for at least 4 hours in a Soxhlet apparatus. The Lavandula atriplicifolia extract acts by both stimulating osteogenesis and inhibiting adipogenesis. The composition may be used to form drug compositions for treating bone loss.