Osteoporosis is the most common metabolic bone disease (2); and caused by bone density loss due to age-related changes during bone formation period as well as the internal and external factors aggravating the process. of antibodies against HP and BMD. Conclusion: According to the findings of this study, H. pylori contamination is not associated with BMD changes in the elderly population. strong class=”kwd-title” Key Words: Helicobacter pylori, Osteoprosis, Bone mineral STK3 density, Elderly patients Osteoporosis is defined as the reduction of bone mineral density, which is usually common in postmenopausal women. But it also occurs in men and women with the underlying causes or risk factors related to bone demineralization (1). Osteoporosis is the most common metabolic bone disease (2); and caused by bone density loss due to age-related changes during bone formation period as well as the internal and external factors aggravating the process. These changes may be added to the low peak bone mass (1, 3). Several underlying diseases, including genetic and the acquired ones can reduce bone mineral content and increase the risk of osteoporosis; among which are the endocrine PJ34 disorders, organ transplantation, chronic inflammatory diseases, malignancy and gastrointestinal diseases and taking some medications (1). Among the many factors that play a role in osteoporosis and bone loss, inflammation is the important one. Inflammation exerts a significant effect on bone mass. Several cytokines regulate osteoblasts and osteoclasts (4). Chronic inflammatory diseases decrease bone formation and increase bone resorption (5). The relation of several gastrointestinal diseases such as malabsorption syndrome, PJ34 gastrectomy, inflammatory bowel disease (IBD) and taking some medications such as proton pump inhibitors (PPI) with bone density loss have been shown (1, 2, 6). Chronic gastritis due to HP is usually chronic inflammatory disease which persists for a long time, gastritis may release several cytokines resulting in bone loss. In chronic gastritis eradication of HP infection can reduce inflammation significantly (7-11). In addition, HP infection may be associated with a number of endocrine disorders (10, 12-14). Considering the high prevalence of HP contamination in Mazandaran of Iran (78%) (15), so this study was designed to find any association between this contamination and loss of bone density in this region. The objective of this study was to determine BMD in patients with helicbacter pylori contamination versus HP unfavorable participants. Methods This research is a part of a comprehensive Amirkola Health and Ageing Project (AHAP) which was done on 1616 participants about 60 years and older between 2011-2012 in Amirkola town (16). Based on the exclusion criteria, 649 patients were excluded. And finally, 967 patients were eligible for the study. Exclusion criteria included the following: history of chronic inflammatory diseases (RA, SLE, AS, IBD), history of cancer, history of antibiotic treatment affecting H. pylori during the past two months, history of diseases affecting bone metabolism (chronic liver disease PJ34 – chronic kidney disease C hyperthyroidism), history of drugs like calcium – vitamin D – Fluoride – bisphosphonates – calcitonin – HRT in recent years, and PJ34 a total vegetarian diet. For the inclusion criteria in the study, besides the completion of the questionnaire based on the absence of exclusion criteria, the blood samples were taken and the level of anti-HP IgG antibody was measured by ELISA method using Patton kits made in Iran. They were also referred to the department of radiology to investigate the density of bone and PJ34 bone mineral density (BMD) of the lumbar spine (L1-L5) and femoral neck were measured by LEXXOS made in France Model 2007 and was shown with BMD (gr / cm2); and T-Score -2.5 was considered as osteoporosis. Besides BMD, height and weight were measured and BMI was calculated as well. The study population, according to the level of antibodies against H.pylori, were divided into two HP+.