Which are risk factors for gallstone formation?

• A. Regular exercise
• B. Age alone
• C. Obesity, rapid weight loss, female sex, age, genetics
• D. High-fiber diet

Answer: (C)

Gallstone formation is driven by factors that increase bile cholesterol and slow gallbladder emptying, leading to cholesterol crystallization. Obesity boosts hepatic cholesterol secretion into bile and can impair gallbladder motility, promoting supersaturation and stone risk. Rapid weight loss causes a surge of cholesterol into the bile as fat stores are mobilized and may also reduce gallbladder contraction, both favoring stone development. Female sex, influenced by estrogen, raises cholesterol in bile and can decrease bile acids, with pregnancy further slowing gallbladder emptying—all increasing risk. Age adds risk with longer exposure and gradual changes in bile composition and motility. Genetics reflect inherited tendencies in cholesterol metabolism and gallbladder function that predispose to stone formation. Choices that involve regular exercise or a high-fiber diet point toward protective effects, not increased risk, so they don’t fit as risk factors.