Your Diet After Weight Loss Surgery

You’ll Meet With a Nutritionist

Patients are required to consult with a nutritionist before surgery. Counseling after surgery is available on an individual basis as needed or required by your physician.

Changing Eating Patterns and Food Choices

You will be provided with materials that clearly outline expectations regarding your diet and compliance to guidelines for the best outcome based on your surgical procedure. After surgery, health and weight loss are highly dependent on patient compliance with these guidelines. You must do your part by restricting high-calorie foods, by avoiding sugar, snacks and fats, and by strictly following the guidelines set by your surgeon.

Never Eat Between Meals

Snacking, nibbling or grazing on foods, usually high-calorie and high-fat foods, can add hundreds of calories a day to your intake, defeating the restrictive effect of your operation. Snacking will slow down your weight loss and can lead to regain of weight.

The Best Choices of Protein

Eggs, low-fat cheese, low-fat cottage cheese, tofu, fish, other seafood, chicken (dark meat), turkey (dark meat) are some of the best choices of protein. 60 to 70 grams a day are generally a sufficient amount of protein. Check with your surgeon to determine the right amount for your type of surgery.

Drink Lots of Water

When you are losing weight, there are many waste products to eliminate, mostly in the urine. Some of these substances tend to form crystals, which can cause kidney stones. A high water intake protects you and helps your body to rid itself of waste products efficiently, promoting better weight loss. Water also fills your stomach and helps to prolong and intensify your sense of satisfaction with food. If you feel a desire to eat between meals, it may be because you did not drink enough water in the hour before.

Dumping Syndrome (only for gastric bypass)

Eating sugars or other rich or fatty foods when you have an empty stomach can cause dumping syndrome in patients who have had a gastric bypass. Although we do not fully understand the body’s reaction to these foods, the result is a very unpleasant feeling: you break out in a cold clammy sweat, turn pale, feel "butterflies" in your stomach, and have a pounding pulse. Cramps and diarrhea may follow. This state can last for 30-60 minutes and can be quite uncomfortable - you may have to lie down until it goes away. This syndrome can be avoided by not eating the foods that cause it, especially on an empty stomach. A small amount of sweets, such as fruit, can sometimes be well tolerated at the end of a meal.

Red Meat

You can, but you will need to be very careful, and we recommend that you avoid it for the first several months. Red meats contain a high level of meat fibers (gristle) which hold the piece of meat together, preventing you from separating it into small parts when you chew. The gristle can plug the outlet of your stomach pouch and prevent anything from passing through, a condition that is very uncomfortable.


You will need to take a daily multivitamin for the rest of your life. B12 may also need to be taken orally or sublingually (under the tongue) by many patients and calcium supplementation and vitamin D is recommended to help prevent bone calcium loss. Other supplements may be prescribed by your surgeon.

Restriction on Salt or Spicy Foods

Your salt intake will be unchanged unless otherwise instructed by your primary care physician.

Most patients are able to enjoy a wide variety of foods, including spices.

Alcohol Consumption

No matter which bariatric surgery you have, you will find that even small amounts of alcohol will affect you quickly. CAUTION for gastric bypass and sleeve gastrectomy patients: You will process alcohol into your system much more rapidly than before surgery and can have higher blood alcohol levels with less intake. It is suggested that you drink no alcohol for the first year.

Milk Products

Milk contains lactose (milk sugar) which is not well digested in some people. This sugar passes through undigested until bacteria in the lower bowel act on it, producing irritating byproducts as well as gas. Depending on individual tolerance, some persons find even the smallest amount of milk can cause cramps, gas and diarrhea, while others find no difference after surgery.