Gastrectomy is an operation which partially or completely removes the stomach. When this is done the end of your oesophagus (your gullet) is joined to the first part of the small intestine, which is called the duodenum.

Your stomach normally holds food after a meal and partially digests it before releasing it in small quantities into your duodenum. When your stomach is partially or completely removed it means that large amounts of food pass very rapidly from your gullet to your small intestine.

When undigested food goes into your small intestine in this way it absorbs a lot of fluid from the fine blood vessels in the wall of the intestine. This causes the food to swell and stretch your intestine, which can lead to nausea, vomiting and diarrhoea. The loss of fluid from the body, which is drawn into the food in your intestine, can also cause a fall in the blood pressure, this leads to dizziness, weakness and sweating.

This problem of profuse sweating, nausea, dizziness and weakness soon after eating, in people who have had a gastrectomy, is called dumping syndrome.

The best way to reduce the chances of this happening is to alter your diet and eating patterns. Having two or three large meals a day with plenty of fluids is the most likely way to cause dumping syndrome after a gastrectomy. Having small, high calorie, high protein meals with drier food, five or six times day can often help to reduce the chances of it occurring. It can also be helpful to have drinks in between meals rather than when you are eating. Avoiding foods that contain high levels of sugars can also help, as does having some fat in your meals, as this slows the rate at which food passes into the intestine.

If you discuss your problem with your doctors they should be able to put you in touch with a dietitian who could help give you detailed advice about adjusting your diet and eating patterns.