Response of immature bone-ligament junction to a high-fat-sucrose diet

A high-fat-sucrose diet can adversely affect calcium absorption, and thus bone-ligament junction strength may be compromised. To test this premise we examined the influence of a high-fat-sucrose diet on the femur-medial collateral ligament-tibia complex of rats. The mechanics and geometry of this bone-ligament-bone complex were measured, and the histomorphometry of the distal bone-ligament junction (tibial-medial collateral ligament) was examined. After 10 weeks the high-fat-sucrose and control (low-fat, complex-carbohydrate) diet groups showed no difference in medial collateral ligament cross-sectional area, but the mechanical integrity of high-fat-sucrose bone-ligament-bone complex was significantly less than the controls; for example, the maximum and failure loads were significantly less (30%) with the high-fat-sucrose diet. Cell density was also significantly less in the medial collateral ligaments of those rats on the high-fat-sucrose diet. Diets with relatively high proportions of fat and sucrose are not uncommon in North American and European nations, but little is known about the effects that these diets may have on growing bone and fibrous connective tissues. The results from the current study provide both a caution and a stimulus. The caution arises from the pronounced and adverse effects that a diet rich in fat and sucrose can have on the mechanical properties and structure of bone-ligament junctions in growing animals. The stimulus provided by these results is to examine the long-term consequences of such a diet on bone-ligament integrity and to assess the implications of a high-fat-sucrose diet for humans.