Weight loss surgery may be a useful tool to help you lose weight and manage medical conditions associated with obesity. All complications and risks need to be discussed with your doctor. An educated decision can then be made. Your dietitian is a vital member of your medical team and is best qualified to manage your nutritional needs both before and after surgery.

Weight loss surgery should be considered after all other weight loss avenues have been explored. All options should be discussed with your G.P. and a referral needs to be made to a bariatric surgeon, where all risks and the nature of the surgery are explained.

In preparation for surgery, a very low energy diet (VLED) is recommended. A nutritionally complete meal replacement is chosen, which means that it can be used as a sole source of nutrition. This diet is usually followed for 2-3 weeks prior your scheduled date. This is an intense prescriptive diet which involves 3 meal replacement shakes, 1 teaspoon of vegetable oil (to stimulate the gallbladder), 2 litres of fluid and an additional protein source (for individuals greater than 100kg). This is possibly the most challenging stage of weight loss surgery, as short-term side effects such as headaches, lethargy, feelings of hunger and moodiness may occur.

After surgery, a Fluid Diet is commenced for 2 weeks. This allows for healing and limits the risk of blockage. A general target of 60 grams of protein and 1.5 litres of fluid is set. The use of protein powder supplements significantly supports you to reach your protein target. Meal replacement shakes are used and help to nourish your body whilst on the Fluid Diet.

Following this, a Puree Diet is implemented for 2 weeks. A food processor or stick blender is needed as food must be smooth, moist and lump free. The protein requirements also increase, as food is slowly introduced. Initially, only 1 to 2 tablespoons may only be tolerated. Multivitamin and calcium supplements are also started, with a fibre supplement used only if needed.

Finally, if the Puree Diet is tolerated well, then you may progress to a Soft Diet for 2 weeks. This is quite similar to the Puree Diet, although food does not need to be blended. Food should be easily cut and mashed with a fork. The key to success is to ensure that all food is moist. Roasting and barbequing results in food drying out, so casseroles and stews are preferred.

If the Soft Diet is tolerated well, then 7 weeks post surgery you may commence a Normal Textured Diet. Up until 6 months post surgery, you may tolerate ¼ to ½ cup of food. However, 6 months post surgery, this portion may increase to ½ to 1 cup of food. High sugar beverages need to be limited as they may sabotage your weight loss goals. Some foods may still need to be eaten with caution. For example, calamari may be too rubbery whilst bread may absorb water and expand.

Your dietitian is an important member of your medical team and may help to:

-provide advice during your modified textured diets  

-advise you on supplements you need post surgery

-calculate your protein requirements and devise a protein food list

-assign you an adjusted ideal body weight (AIBW) target

-provide you with meal ideas

-give you practical strategies to problems you may be experiencing

-help you with meal planning

 

The above is a general summary of weight loss surgery. Please contact me if you have any additional queries. An appointment can also be made at any of my private practice locations.

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Written by 
Mary-Anne Chamoun
Mary-Anne is an Accredited Practising Dietitian and Accredited Nutritionist who has been working in a clinical setting since 2007. She has a particular interest in managing diabetes, malnutrition, IBS, inflammatory bowel disease, and weight loss.