Bowman-Birk Inhibitor Concentrate in Preventing Cancer in Healthy Men

Inclusion Criteria: * Healthy volunteer * Male * Performance status - ECOG 0-2 * RBC normal * WBC ≥ 3,000/mm\^3 * Platelet count normal * Hemoglobin normal * Hematocrit normal * ALT and AST normal * Bilirubin normal * Creatinine normal * No history of heart disease * EKG normal * No history of pancreatitis or obstruction of pancreatic ducts * No history of pancreatic cancer or pancreatic adenoma * Amylase normal * Lipase normal * Cholesterol normal * Triglycerides normal * Serum glucose ± 10% of normal * Within 15% of ideal body weight * No history of chronic medical condition * No history of excessive alcohol consumption (i.e., \> 2 alcoholic beverages per day on average) * No history of amyloidosis * Non-smoker * Former smokers are eligible provided they have not smoked within the past 3 months * No history of medical condition that would influence gastrointestinal uptake of the study drug * No history of diabetes mellitus * No allergy or prior adverse reaction to soybeans * Not a vegetarian * No diagnosis of cancer within the past 5 years except nonmelanoma skin cancer * No evidence of other life-threatening disease * No evidence of psychiatric problems * More than 12 months since prior chemotherapy * More than 1 month since prior experimental drugs * More than 3 days since prior consumption of alcoholic beverages * More than 2 weeks since prior and no concurrent regular use (i.e., \> 3 times/week) of nonsteroidal anti-inflammatory drugs * More than 2 weeks since prior multivitamin tablets (or other vitamin supplements) of \> 2 per day * No more than 2 multivitamin tablets (or other vitamin supplements) per day during study participation * No more than 1 serving of tofu, soy milk, or other primarily soy-based food per day