More Unsaturated Fats, Fewer Gallstones?
Eating Monounsaturated and Polyunsaturated Fat Lowers Risk of Gallstones
Oct. 4, 2004 -- Eating more olive oil and less butter may help men lower their risk of gallstones, a new study shows.
Researchers found men who ate a diet high in monounsaturated or polyunsaturated fats, such as those found in plant and olive oils, were 18% less likely to develop gallstones than men who ate the least of these types of fat.
Previous studies have shown that the type of fat people eat may affect their risk of developing gallstones. For example, diets high in saturated fats, such as those found in red meat and whole milk, may promote the formation of gallstones.
This study adds that in addition to keeping saturated fats to a minimum, eating a diet rich in unsaturated fats, which includes both polyunsaturated fats and monounsaturated fats, may further lower men's risk of gallstones.
Gallstones are caused by changes in bile, which is a fluid produced by the liver to help digest food. Bile contains a mixture of cholesterol, fats, and other substances.
When changes in bile occur, such as too much cholesterol, it can cause bile to crystallize and form gallstones. Cholesterol gallstones account for nearly 80% to 90% of all gallstones removed from middle-aged adults.
The Type of Fat Matters
In the study, published in the Oct. 5 issue of the Annals of Internal Medicine, researchers compared the diets of more than 45,000 men between the ages of 40 and 75. None of the men had a history of gallstones or gallbladder disease.
After 14 years of follow up, researchers found men who ate the most unsaturated fat were 18% less likely to develop gallstones compared with the men who ate the least. This protective effect was biggest among men who were heavier and less physically active.
Although this was an observational study and researchers can't prove that the diets high in unsaturated fat were the only thing responsible for the reduction in gallstone risk, they say the findings support the already well-studied notion that eating a diet rich in unsaturated fats may provide a wealth of health benefits.