Do gallstones improve or worsen on a low carb / high fat diet? It’s a common question with an interesting answer.
The gallbladder stores bile, a yellow-green fluid manufactured in the liver. The bile is used to digest the fat you eat. The question is: Is it good or bad for the gall bladder to eat fat?
How to get gallstonesIf you eat low fat less bile is needed to digest your food. More bile thus stays in the gallbladder. Long enough, perhaps, for stones to form. It’s been shown that people who (instead of fat) eat more carbohydrates are at increased risk of gallstones.
It sounds logical. But it’s far from all the evidence. The risk of low fat diets have been tested at least three times:
Studies of extreme low fat diets
- In a study of 51 obese people using an extremely low fat low calorie diet (just one gram of fat a day!) the gallbladder was examined by ultrasound before the diet and after one and two months. After one month four of the 51 participants had developed new gallstones. After two months more than one in four (13 people) had new gallstones! This on an almost fat free diet. Three participants needed to have their gallbladder removed during the study.
- A similar study examined 19 people eating an extremely low fat low calorie diet over 16 weeks. At the ultrasound examination at the end of the study five people (again about one in four) had new gallstones.
- A third study compared an extremely low fat diet with a diet slightly higher in fat during 3 months. More than one in two (6 of 11 people) in the group eating extremely low fat developed new gallstones. Nobody in the group eating more fat did.
What happens if you do the opposite?What if you were to do the opposite of the usual advice? Regularly eat food with fat in it? Then more bile will be used to digest the food. The bile ducts and the gallbladder will be flushed through regularly. Probably no stones will have time to form, and pre-existing stones might (if you are lucky) be flushed out into the small intestine.
The risk is that you will get gallstone pain in the short term – if you already have gallstones.
The question is: Do you want to think short-term (low fat) or long-term (higher fat)?
Does high fat food work?It’s logical to think that food higher in fat can result in a gall bladder free from gallstones. But as far as I know there has not yet been any study testing high fat food to people with gallstones.
On the other hand I know quite a few people who have experienced that their gallstone disease disappeared on a LCHF diet. Sometimes at the expense of initial gallstone attacks though.
A Swedish low carb site conducted a survey of its members. 145 people who used to have gallstones answered what happened since they started eating LCHF. Take the result with a huge pinch of salt as this kind of survey gives very unreliable answers:
This survey gives some support to the theory that high fat food can cure gallstone disease.