Introduction
This topic covers how diet and nutrition can prevent osteoporosis, a disease in which bone mass falls and bone microarchitecture deteriorates, so that bones become fragile and break with little trauma. In the exam you should explain the bone-health basis of prevention, name the key nutrients and their sources, describe the dietary and lifestyle pattern that supports bone, and state what diet can and cannot achieve.
Bone physiology and the aim of prevention
Bone is living tissue that is continuously remodelled by osteoclasts (resorption) and osteoblasts (formation). Peak bone mass is usually reached around the late twenties to early thirties, and the amount built up by then is the largest single determinant of lifetime fracture risk. After that, bone loss proceeds slowly, and it accelerates in women after the menopause because of oestrogen deficiency and in both sexes with ageing. Dietary prevention therefore has three aims:
- maximise peak bone mass in childhood and adolescence;
- slow age-related and menopausal bone loss in adults;
- reduce falls and fracture risk in older people through adequate protein and muscle support.