That's why this study caught my eye:
An Association Between Hypocholesterolaemia And Colorectal Carcinoma In An Irish Population
I've always known that low cholesterol was associated with certain cancers but I wasn't aware of the mechanism. This study postulated one, at least as it applies to colon cancer:
"If the hypocholesterolaemia among colorectal cancer patients is not caused by a metabolic effect of the tumours, how can such a phenomenon be explained? Upon consideration of the hypothesis that bile constituents and their intracolonic degradation products influence colon carcinogenesis, it has been proposed that subjects with a metabolic predisposition towards lowered serum cholesterol may also have an increased secretion of bile and hence an increased risk of developing colorectal carcinoma. Thus, the carcinogenic effects of a high consumption of dietary fat may be more readily produced in subjects who maintain lowered cholesterol concentrations by showing an inherently greater conversion rate to bile acids than the rest of the population. Such a hypothesis could explain the paradoxical inverse relation between serum cholesterol concentrations and colorectal carcinomas detected in certain western, or at least 'westernised' populations."In this case, it isn't the act of reducing the manufacture of cholesterol (via statins) that raises the risk for colon cancer ... it's a genetic predisposition to lose cholesterol by secreting more in bile.
Bile acids are secreted into the intestine in proportion to how much dietary fat is consumed. Bile acids are good in that they help emulsify fats, improving their digestion and absorption. But bile acids can be damaging to the cells that line the colon. This mechanism holds for everyone, but may be more ominous in people with higher levels of bile acid secretion or ineffective reabsorption.
For those who find it ridiculously easy to maintain a low cholesterol, moderating their fat intake may be helpful.