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How Does My Diet Change After Bariatric Surgery?

May 18, 2022

The dietary guidelines provided following surgery are essential for success. First and foremost, they are meant to allow your body to heal from surgery. Going forward, they are meant to help you lose weight appropriately. Any deviation from the dietary guidelines can result in a slowdown in weight loss. The number one goal is to improve your health!

STAGE 1 – DAY 1 TO 21

From the time you get home from the hospital to three weeks after your day of surgery, a full liquid diet is required (beverages, broths, protein drinks). These first three weeks after your surgery are crucial for minimizing complications and maximizing your recovery. Following a full liquid diet for the first 3 weeks after surgery will give your body time to heal. This diet will also help you begin to understand how much food you can eat BEFORE you feel too full. This is a time of learning new behaviors and developing new lifestyle habits.

Many patients ask why they need to be on liquids for three weeks?
Due to swelling, anything thicker than water can easily become stuck, creating a “dam” effect and causing any intake after that to back up and push on the stomach walls. This can stress your new staple line and may result in a leak. A leak from your stomach could be a serious complication. The bottom line: If you aren’t sure you can have it, put it in a strainer. Only that which runs freely and easily through the strainer is part of this phase of the diet. If it doesn’t go through, it is not for you!

The main 3 goals during Stage 1 of the diet are to:

  • Rest the stomach and allow it time to heal
  • Stay hydrated by consuming ≥ 64oz fluid per day
  • Consume adequate amounts of protein to aid in the healing process

STAGE 2 – DAY 22 TO 42

Soft Solid Foods | 3-4 oz. per meal

 Start this diet at Post-Op Day 22 and continue for 3 weeks. You are still learning about your new body. Let your pouch be your guide on portion sizes. Stop eating BEFORE you feel full. Remember to use a food scale to weigh your food. Overeating and not chewing your food thoroughly can lead to nausea, vomiting, and stretching out your stomach. *Start with softer foods like yogurt then transition into soft solid foods like ground turkey by the 3rd week. It is recommended to introduce new foods at dinner time.

Key Points for Healthy Eating Habits

  • Eat slowly: Immediately after surgery, the pouch is swollen and needs time to heal. Eating too quickly may cause you to overfill your new pouch and cause discomfort, nausea, and vomiting.
  • Drink small amounts: Learn to sip slowly. Try not to fill your entire mouth with fluid. Use a 1-ounce (30ml) medicine cup to help determine a safe amount.
  • Stop eating before you feel full: Do not overeat. Listen to your body by eating slowly and mindfully. If you are unable to recognize fullness, eat only the recommended amount and no more at one sitting. Eating and drinking too much will eventually stretch your pouch and prevent you from reaching maximum weight loss.
  • Maintain hydration by consuming at least 64 ounces of fluid during the day. Try to consume protein-rich fluid (1% or skim milk, protein drinks, etc.) as half of your fluid intake between meals. Avoid carbonated beverages for the rest of your life. Increase fluid intake until urine is clear.
  • Protein: Protein is needed by the body to build and maintain tissue, promote wound healing, and fuel the metabolic engine that burns fat. Over the long term, protein will help preserve muscle tissue so weight can be lost as fat. Foods like lean red meat, pork, chicken and turkey without skin, fish, eggs, beans, and low-fat cottage cheese are high in protein and low in fat.

Foods to Avoid

There are different kinds of foods that you should avoid after having bariatric surgery:

  • All raw fruit
  • All raw veggies, including lettuce and tomato
  • Cooked or raw asparagus, celery, corn, or peas
  • Cooked or raw potatoes, sweet potatoes, winter squash and plantains
  • All nuts
  • All high carbohydrate/sugary foods like bread, pasta, rice, crackers, tortillas, chips, dry cereal, cake, cookies, ice cream, etc.
  • Caffeine
  • Alcohol
  • Limit artificial sweeteners

It’s important that you follow the post-op diet instructions and deter from eating certain foods to ensure that you receive the maximum amount of nutrition after your surgery.

While the surgery can help you limit the amount of food you eat, you must be ready to change lifestyle habits that led to weight gain. After surgery, you need to follow the nutritional recommendations and exercise regularly (150 minutes per week of physical activity is recommended). Participation in a support group could help you stick with new habits. It’s also important to keep follow-up medical appointments to monitor the effects of surgery.

About Author
One of the most experienced weight loss surgeons in the country – Dr. Nick Nicholson – along with a full staff of surgeons, physician assistants, and other experienced clinicians, help patients reverse obesity with LAP-BAND, Gastric Bypass, Sleeve Gastrectomy, Gastric Balloon and Revisions.