Many patients have heard that there is a diet progression after bariatric surgery (and possibly before), and a lot of patients report being nervous about the liquid diet. But why is there a diet progression? Why do you have to follow different diets? Let's take a look at a brief description of the common diet progressions and why they are recommended.
This is the one time we readily use the word "diet", as a diet is a short-term change to your eating pattern. For the long term, we prefer to call it a healthy eating plan.
Key takeaways
- A pre-operative diet helps shrink the liver, making surgery safer.
- After surgery, patients usually move from clear liquids to full liquids, puréed, soft and finally solid foods.
- The stages protect the staple line, reduce complications and help you learn your new signs of fullness.
- Add one new food at a time and follow the exact recommendations of your programme.
Examples of diet progressions
The diet progression allows patients to move through different phases, eventually eating solid foods again. The amount of time in each stage may vary according to each surgeon's or dietitian's recommendation, as well as each individual patient. Be sure to follow the exact recommendations of your programme.
| Stage | What it means | Average duration (survey of bariatric dietitians) |
|---|---|---|
| Clear liquids | Adequate fluid and electrolytes; time for the stomach and/or intestines to heal | 1–2 days |
| Full liquids | Slightly thicker (milk rather than water consistency); more calories and nutrients | 10–14 days |
| Puréed | Apple sauce consistency, no solid pieces | Typically 2–4 weeks (more than 10 days) |
| Soft foods | Foods you can mash with a fork | More than 14 days |
| Solid foods | Add new foods slowly, one at a time | – |
Pre-operative
Some surgeons have their patients follow a special diet before surgery. This may be a full-liquid meal plan or a combination of food and high protein meal replacements; some surgeons recommend a low-carbohydrate eating plan. These diets are done to make your surgery safer.
In many obese patients, the liver is enlarged. The liver sits in front of the stomach, and to operate safely in laparoscopic procedures it is held out of the way by a retractor. If the liver is too large, it may not stay within the retractor, which increases the risk of surgical complications. Following a low-carbohydrate, low-fat and low-calorie diet (liquid or food) allows the liver to shrink, making surgery safer.
Post-operative diets
Most patients start on a liquid diet immediately after surgery (clear or full; some programmes use a clear liquid phase and then progress to full liquids). The length of time on the liquid diet varies from programme to programme.
A clear liquid diet allows an adequate intake of fluid and electrolytes, and gives your stomach and/or intestines (depending on which surgery you had) time to heal, reducing your risk of post-operative complications. Based on one survey of dietitians working in bariatrics, this stage averaged 1–2 days.
Full liquid diet
A full liquid diet is slightly thicker (more like a milk consistency than a water consistency) and allows more calories and nutrients to promote healing and reduce the risk of complications. Based on one survey of dietitians working in bariatrics, this stage averaged 10–14 days.
Puréed
Most dietitians describe the puréed stage as eating foods with an apple sauce consistency. This stage typically lasts 2–4 weeks, but may vary from programme to programme, as do the other stages. Typically there are no solid pieces during this stage, and most patients are still sensitive to spicy or dairy foods. A puréed diet allows you to gradually increase your tolerance of foods in your stomach and intestines. Based on a survey of bariatric dietitians, this stage lasted more than 10 days.
Soft foods
Typically, if you can mash the food with your fork, it is acceptable to eat. This stage allows patients to eat foods that pass easily through the stomach to the intestines. Based on a survey of bariatric dietitians, this stage lasted more than 14 days.
Solid foods
Spicy foods, among others, may still be difficult to tolerate. It is important to start slowly and add new foods one at a time to determine exactly what you can tolerate.
Safety
One of the biggest reasons for the different diets is safety. The diet progression allows the staple line of your stomach (in gastric bypass and/or sleeve gastrectomy) to heal without being stretched by the foods you eat. It also allows you to adjust to eating smaller amounts and learn what is digested comfortably and safely. Following the recommended diet progression helps avoid side effects and complications. Risks of not following your recommended diet progression properly include:
- Dumping syndrome: after a gastric bypass, you might experience dumping syndrome if you eat foods high in sugar (or even simple carbohydrates, e.g. mashed potatoes, white bread, white pasta) or fat.
- Dehydration: one of the most common reasons patients are readmitted to hospital after bariatric surgery. Some programmes recommend not drinking with meals, making it difficult to reach the recommended fluid intake, and it is difficult to drink large amounts immediately after surgery. Starting with a liquid diet increases your chances of achieving your fluid goals.
- Reflux: following the proper diet stages will also help minimise acid reflux.
- Nausea and vomiting: eating too much, eating too fast, not chewing your food properly and eating foods before they are recommended may cause nausea and/or vomiting after bariatric surgery.
- Constipation: not eating regularly, not drinking enough fluid, not eating fibrous foods and not exercising (or being physically active) may increase your risk of constipation after surgery.
- Satiety: satiety is the feeling of fullness. Following the recommended diet stages will help you re-learn your feeling of fullness and avoid overeating.
Learning which foods you tolerate
Going through the different diet stages helps you learn your new signs of fullness and which foods you can tolerate. As you progress, try only one new food at a time. Certain foods may not be tolerated, and this varies between individuals. Chew each new food to an apple sauce consistency before swallowing. If a food causes discomfort, avoid it and try again in a couple of weeks. Most often, patients can tolerate the majority of foods over time.
Think of this diet progression like feeding a baby. Just as a baby progresses from liquid (breast milk or formula) to puréed (like apple sauce) to soft (like mashed sweet potato without the skin) to regular food, so will you. Once babies start solid food, they add one food at a time, decreasing the risk of food allergies. We are not concerned about allergies with bariatric surgery patients here, but you can see the similarities.
Keeping a food journal may help you see which foods you tolerate well and which may need to be saved for later. Journaling can also help you understand emotional triggers. Do not just write down the foods: also record the amounts, how you felt that day (happy, stressed, etc.) and how well each food was tolerated.
Energy and healing
By following the recommended diet plan, you will consume adequate energy (calories) and nutrients, which are necessary to support healing. Adequate protein and calories also help maintain lean muscle mass, as muscle mass is often lost during extreme weight loss. This is important because muscle mass helps keep your metabolism burning at a higher rate (burning more calories per day), even at rest.
Every patient and every surgery is different. Follow the instructions of your physician and/or dietitian to reduce your risk of surgical complications – the stages may vary from surgery to surgery or differ in length. As much as these stages are not fun, they serve a purpose and they are not forever! You will be eating regular food in a short time, and all of this will be well worth it.
This article is for general information only and does not replace personal medical advice. Always discuss your situation, blood test results and supplementation with your bariatric team or healthcare provider.