Dear doctor, do I have to follow a special diet before weight loss surgery?

20 March 2018

Q: I’ve been considering weight loss surgery for a while now. Do I have to follow a special diet before I have the surgery?

A: In my experience many patients have previously tried to lose weight by drastic diet change and found that weight either plateaus after 1-2 stone or they regain weight over time which can be extremely discouraging.

Weight loss surgery provides a ‘tool’ to start approaching weight management differently. All the surgeries will help reduce portion sizes of good food so healthy eating principles still apply. Some patients say they have always felt hungry so surgery can help in these cases too, although it won’t help if hunger is predominantly from emotional origins.

There are however some foods which could lead to surgery being less effective, so behaviour change is key. These include:

  • Regular eating: this keeps your new surgical pouch small therefore maximising weight loss. If you currently skip meals it is important you change your eating habits if you are considering surgery.
  • Crisps and biscuits: these textures are soft, calorific and “slip through”. We encourage you to switch over to more suitable snacks.
  • Alcohol and fizzy drinks: fluid hydrates but alcohol is calorific so is best avoided. All fizzy drinks, including diet options, will stretch your tiny pouch so we advise to quit this too.

Although the above changes may seem daunting, you will be provided with regular support during your bariatric journey. Most patients find that the benefits of dietary change after surgery far outweigh the demands of lifestyle change.

Ms Frances Hay is a Dietitian (part of multidisciplinary weight loss surgery team) at Spire Portsmouth Hospital.

The content of this article is provided for general information only, and should not be treated as a substitute for the professional medical advice of your doctor or other health care professional.

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