How does gastric bypass surgery work?

During Roux-en-Y gastric bypass surgery (gastric bypass) the top of the stomach is stapled to form a small pouch. The small pouch becomes a new, smaller stomach and is totally separate to the rest of the stomach. This small pouch is then ‘re-plumbed’ to the jejunum, the middle part of the small intestine, bypassing the first part of the intestine called the duodenum.

During Roux-en-Y gastric bypass surgery (gastric bypass) the top of the stomach is stapled to form a small pouch. The small pouch becomes a new, smaller stomach and is totally separate to the rest of the stomach. This small pouch is then ‘re-plumbed’ to the jejunum, the middle part of the small intestine, bypassing the first part of the intestine called the duodenum.

The new, smaller stomach pouch allows you to eat only a small amount of food before feeling satisfied. There are also some hormonal changes that occur help to decrease your appetite.

It is important to note that bypassing the first part of the intestine means less vitamins and minerals are absorbed. This is why it is essential that you follow the advice of your team regarding vitamin and mineral supplementation.

Maintenance

Unlike the gastric band, the gastric bypass does not require any ongoing adjustments. However, follow up is necessary to ensure your weight loss is appropriate, you are receiving adequate nutrition and that the surgery is not having any negative effects on your health.

One study has found the most intense weight loss occurs in the first six months following gastric bypass surgery and will slow in the second six months, stabilising in the second year. It is likely, however, that everyone will have a different experience.

As with all forms of weight loss surgery, success is not guaranteed. Lifestyle changes including healthy eating and regular physical activity are key ingredients in your long term success following surgery. Whilst the size of the new stomach helps prevent overeating, the food choices you make are important. People who maintain their weight losses long term generally avoid high fat, high-energy foods.

As well as improving weight loss and maintenance, it is important to avoid high sugar and/or high fat foods as following gastric bypass surgery they can lead to a side effect called dumping syndrome. See a simple explanation of dumping syndrome here.

A 2012 study showed that following gastric bypass surgery, those who kept in closest contact with their support team achieved better results. Your team is there to guide you to get the best results following surgery, so make the most of them and keep in touch! They have all sorts of hints and tips to help you on a successful journey.