This study examined the risk indicatorsfor alveolar bone loss associated with periodontal infection. A cross‐section of 1,361 subjects aged 25 to 74 years, from Erie County, NY were evaluated for interproximal alveolar bone loss and potential explanatory variables including age, gender, history of systemic diseases, smoking, and presence of 8 subgingival bacteria. Interproximal alveolar bone loss was measured from the alveolar crest to the CEJ and a mean computed for each subject. The mean bone loss per subject (BL) ranged from 0.4 to 8.8 mm, and this outcome variable was grouped into 4 ordered categories. The degree of association between the explanatory variables and BL was examined utilizing an ordinal stepwise logistic regression model. Factors which were positively associated with more severe bone loss included subgingival colonization withB. forsythus(O.R. 2.52; 95% CI: 1.98 to 3.17) orP. gingivalis(O.R. 1.73; 95% CI: 1.27 to 2.37), race (Native American, Asian, or Pacific Islanders) with an O.R. 2.40 (95% CI: 1.21 to 4.79), and gender with males having higher odds than females. Smokers had greater odds for more severe bone loss compared to non‐smokers ranging from 3.25 (95% CI: 2.33 to 4.54) to 7.28 (95% CI: 5.09 to 10.31) for light and heavy smokers, respectively. Individuals at older ages also showed more severe levels of bone loss. History of kidney disease (O.R. 0.55; 95% CI: 0.35 to 0.89) and history of allergies (O.R. 0.76; 95% CI: 0.59 to 0.98) were inversely associated with severity of bone loss. Severity of alveolar bone loss is associated with increasing age, smoking, race, and colonization with subgingivalB. forsythusorP. gingivalis. This and other studies directed to identifying true risk factors associated with periodontal disease may lead to preventive measures directed to reducing the deleterious effects of modifiable risk factors.J Periodonol 1995;66:23–29.