Dealing with doctors over your diabetes diet

Q: My friend had to have a gallstone operation and was told go on a low-fat diet. I have also been told that eating lots of fat causes gallstones. Will I develop gallstones eating this way?

A: Quite the reverse — a fatty diet actually prevents gallstones. Elaine was told by her doctor that her gall stones were caused by following a low-fat diet. John was told that his gallstones were caused by eating a high-fat diet. Isn't it infuriating when doctors give out such contradictory advice? So let me put the record straight.

Fair, fat and forty. That is the general perception of someone with gallstones. For this reason, gallstones, often found in fat people, are usually attributed to a diet high in fats. In fact this is the opposite of the truth: Gallstones are caused by eating too little fat rather than too much.

Fats are not soluble in water. Before dietary fat can be digested, it has to be emulsified. That is what bile is used for. The liver makes bile continuously and stores it in the gall bladder until such time as it is needed. Gallstones are formed when the gall bladder is not emptied on a regular basis — because you aren't eating fat.

Low-fat slimming diets are probably the major cause. All such diets restrict fats. In people who eat a low-fat diet, bile is stored for long periods in the gall bladder — and it stagnates. In time — and it can be really quite a short time — a 'sludge' begins to form. This then coagulates to form small stones, called 'gravel' which then become bigger. The speed with which this happens was dramatically demonstrated in a trial at several American university hospitals.²² None of the subjects had any sign of gallbladder disease at the start of the study. However, after only eight weeks of low-fat, weight-reduction dieting, more than a quarter had developed gallstones. Where they were fed intravenously, half developed gall bladder sludge after 3 weeks, and all had developed sludge by six weeks. Nearly half of those who developed sludge also developed gallstones. This is an alarming finding as gallstones are not only painful, the operation to remove them is potentially life-threatening. The more one uses low-fat diets, the greater is the risk.

The pain that someone with gallstones gets is when these are passed with the bile in response to a fatty meal and get stuck in the bile duct.

So, it is a low-fat diet which causes the gallstones but it is eating a high-fat diet that makes them apparent. If you eat a low-fat diet and never eat fat again, then you probably won't get the pain, even though the stones are there.

If someone suffers from gallstones, a low-fat diet 'prevents' the symptoms, so doctors often suggest such a diet. But it makes the cause of the symptoms (gallstones) worse. Doctors are often loath to operate to remove the stones, so just preventing you knowing about them seems to them to be a good compromise — despite the fact that you will then be miserable and hungry as a result!