Calcium and Vitamin D

Introduction

Osteoporosis is a skeletal disorder characterized by compromised bone strength, which ultimately predisposes individuals to an increased risk of fracture. The disorder results from a disturbance in the bone-remodeling cycle, whereby bone resorption exceeds bone formation. This bone loss and skeletal fragility then predispose individuals to the increased risk of fractures, most commonly involving the hip, wrist, and vertebrae.

Fractures are accompanied by considerable morbidity and mortality and are a source of substantial health care expenditures. Estimated direct costs associated with fractures resulting from osteoporosis are as high as $10 billion to $15 billion per year in the U.S; when indirect costs are included, values in a single year have been as high as $94 billion. In 1990, 1.3 million to 1.7 million hip fractures occurred worldwide. By the middle of the 21st century, this number is expected to increase steadily to six million per year.

Common risk factors for osteoporosis and subsequent fracture include Caucasian or Asian descent, early menopause, physical inactivity, cigarette smoking, excessive alcohol consumption, low body mass index (BMI), chronic steroid therapy, and hypogonadism. Another significant risk factor is an individual’s nutritional status, especially with respect to vitamin D and calcium intake and utilization. canadian antibiotics

In this article, we discuss the newest concepts in the literature as they relate to the pharmacology, clinical efficacy, and toxicity of calcium and vitamin D in preventing and treating osteoporosis. Today, optimal medical management of this disease includes the additional use of antiresorptive agents such as bisphosphonates, selective estrogen receptor modulators (SERMs), calcitonin, and osteoblast-stimulating agents such as teriparatide (Forteo, Lilly). However, these topics are addressed in other texts and reviews and are not discussed within the context of this article.