High fat diets could prevent gallstone formation

This study was published in the International Journal of Obesity and Related Metabolic Disorders 1998 Jun;22(6):592-600

Study title and authors:
Gallbladder motility and gallstone formation in obese patients following very low calorie diets. Use it (fat) to lose it (well).
Festi D, Colecchia A, Orsini M, Sangermano A, Sottili S, Simoni P, Mazzella G, Villanova N, Bazzoli F, Lapenna D, Petroni ML, Pavesi S, Neri M, Roda E.
Department of Medicine and Aging, University G D'Annunzio Chieti, Italy.

This paper can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/9665682

The principal aim of this study was to evaluate the long term effects of two very low calorie diets differing in fat content on gallstone formation in obese subjects. The dieters (who were free of gallstones at the start of the study) were allocated to either a low calorie low fat diet or a low calorie high fat diet for six months.

The study found:
(a) Twenty-two subjects concluded the study, eleven in each group, and a significant weight loss was achieved by all subjects.
(b) Gallstones (asymptomatic) developed in 6/11 (54.5%) of subjects following the lower fat diet, but in none with the higher fat regimen.
 
The author concluded: "In the obese during rapid weight loss from a very low calorie diet, a relatively high fat intake could prevent gallstone formation".