How Many Calories Should I Eat After Gastric Bypass? After gastric bypass surgery, you have probably been told that you can eat whatever you want as long as you do not exceed a certain amount of calories per day. This might be causing you to wonder how many calories should i eat after gastric bypass?
Calories are an important part of the diet when you have had a gastric bypass. You need to understand and know the amount of calories that your body needs to function properly and also not regain the weight after losing it surgically.
How Many Calories Should I Eat After Gastric Bypass
Definition
People who are recovering from sleeve gastrectomy and gastric bypass surgery, also known as Roux-en-Y gastric bypass, can rehabilitate and alter their eating patterns with the aid of a gastric bypass diet.
You will discuss the diet you will need to follow following surgery with your doctor or a qualified dietitian, who will explain what kinds of food and how much you can consume at each meal. You can lose weight safely by adhering to your gastric bypass diet strictly.
Purpose
The gastric bypass diet is designed to:
- Allow your stomach to heal without being stretched by the food you eat
- Get you used to eating the smaller amounts of food that your smaller stomach can comfortably and safely digest
- Help you lose weight and avoid gaining weight
- Avoid side effects and complications from the surgery
Diet details
Diet recommendations after gastric bypass surgery vary depending on your individual situation.
To help you gradually transition back to eating solid foods, a gastric bypass diet often uses a tiered approach. How quickly your body heals and adapts to the change in eating habits determines how quickly you advance from one phase to the next. After surgery, you can normally resume eating regular meals around three months later.
At each stage of the gastric bypass diet, you must be careful to:
- Drink 64 ounces of fluid a day, to avoid dehydration.
- Sip liquids between meals, not with meals. Wait about 30 minutes after a meal to drink anything and avoid drinking 30 minutes before a meal.
- Eat and drink slowly, to avoid dumping syndrome — which occurs when foods and liquids enter your small intestine rapidly and in larger amounts than normal, causing nausea, vomiting, dizziness, sweating and diarrhea.
- Eat lean, protein-rich foods daily.
- Choose foods and drinks that are low in fats and sugar.
- Avoid alcohol.
- Limit caffeine, which can cause dehydration.
- Take vitamin and mineral supplements daily as directed by your health provider.
- Chew foods thoroughly to a pureed consistency before swallowing, once you progress beyond liquids only.
Liquids
For the first day or so after surgery, you’ll only be allowed to drink clear liquids. Once you’re handling clear liquids, you can start having other liquids, such as:
Liquids you can have during stage 1:
- Broth
- Unsweetened juice
- Decaffeinated tea or coffee
- Milk (skim or 1 percent)
- Sugar-free gelatin or popsicles
Pureed foods
You can start eating foods that have been strained and pureed (mashed up) after about a week of coping with liquids. The combination shouldn’t contain any chunks of food and should have the consistency of a thick paste or smooth liquid.
Three to six modest meals each day are OK. There should be 4 to 6 tablespoons of food at each meal. Eat slowly; give each meal 30 minutes.
Choose foods that will puree well, such as:
- Lean ground meat, poultry or fish
- Cottage cheese
- Soft scrambled eggs
- Cooked cereal
- Soft fruits and cooked vegetables
- Strained cream soups
Blend solid foods with a liquid, such as:
- Water
- Skim milk
- Juice with no sugar added
- Broth
Soft foods
You can add soft foods to your diet after a few weeks of eating only pureed meals, if your doctor gives the go-ahead. They ought to be bite-sized, delicate, and simple to chew meal bits.
Three to five modest meals each day are OK. Every meal should contain between a third and a half cup of food. Before swallowing, chew each bite until the meal resembles mush.
Soft foods include:
- Ground lean meat or poultry
- Flaked fish
- Eggs
- Cottage cheese
- Cooked or dried cereal
- Rice
- Canned or soft fresh fruit, without seeds or skin
- Cooked vegetables, without skin
Solid foods
On the gastric bypass diet, you can gradually resume eating firmer foods after around eight weeks. Start by eating three meals every day, each containing one to one and a half cups of food. It’s critical to stop eating before you reach full satisfaction.
You might be able to change the frequency of meals and the quantity of food served at each one depending on how well you handle solid food. Discuss your dietary needs with your dietitian.
Eat one new food at a time. Following gastric bypass surgery, some foods may induce discomfort, nausea, or vomiting.
At this point, foods that may be problematic include:
- Breads
- Carbonated drinks
- Raw vegetables
- Cooked fibrous vegetables, such as celery, broccoli, corn or cabbage
- Tough meats or meats with gristle
- Red meat
- Fried foods
- Highly seasoned or spicy foods
- Nuts and seeds
- Popcorn
Over time, you might be able to try some of these foods again, with the guidance of your doctor.
Dietary Guidelines After Bariatric Surgery

It is crucial to adhere to the suggested dietary recommendations after having bariatric surgery. These recommendations were carefully crafted by your healthcare professionals with the intention of reducing the number of calories you consume while offering balanced meals that support the preservation of lean muscle mass and the prevention of nutrient deficits.
At first, this new eating regimen may seem daunting, but most patients discover that after a while, the rules have subconsciously become a part of their daily routine.
General Guidelines
- Consume balanced meals in moderation.
- Consume food that is low in calories, fats, and sugar.
- Keep a daily log of your dietary quantities, protein, and calorie intake.
- Eat slowly and fully chew each bite of food.
- Steer clear of foods like rice, bread, raw vegetables, fresh fruit, and tough meats like steak and hog. Typically, ground meats are easier to tolerate.
- Do not consume carbonated beverages, eat ice, or use straws. They could make you uncomfortable by introducing air into your pouch.
- Avoid sugar, foods and beverages that include sugar, concentrated sweets, and fruit juices.
- Your daily caloric intake should range between 300 and 600 calories for the first two months after surgery, with an emphasis on thin and thicker liquids.
- One thousand calories should not be consumed each day.
Fluids
- Drink extra water and low-calorie or calorie-free fluids between meals to avoid dehydration. All liquids should be caffeine-free.
- Sip about 1 cup of fluid between each small meal, six to eight times a day.
- We recommend drinking at least 2 liters (64 ounces or 8 cups) of fluids a day. You will gradually be able to meet this target.
- We strongly warn against drinking any alcoholic beverages. After surgery, alcohol is absorbed into your system much more quickly than before, making its sedative and mood-altering effects more difficult to predict and control.
Protein
Consume foods high in protein to preserve muscle tissue. Eggs, meats, fish, seafood, tuna, poultry, soy milk, tofu, cottage cheese, yogurt, and other dairy products are examples of high-protein foods. Your daily protein intake should be between 65 and 75 grams. If you are unable to accomplish this aim in the first few months following surgery, don’t worry.
Supplements
You must take the following supplements on a daily basis to prevent nutrient deficiencies. Please remember that all pills must be crushed or cut into six to eight small pieces. You are not able to absorb whole pills as well as before surgery, and it can be difficult for the pills to pass through your new anatomy.
Multivitamins
Use a daily chewable multivitamin and mineral supplement with a high potency that contains at least 18 mg of iron, 400 mcg of folic acid, selenium, copper, and zinc. This formula is found in products from Centrum Adult chewable multivitamins and Trader Joe’s. After your operation, take two pills a day for at least three months, then one tablet a day for the rest of your life.
Calcium Supplement
Take 1,200 to 2,000 mg of calcium daily to prevent calcium deficiency and bone disease. To enhance absorption, take the calcium in two to three divided doses throughout the day – for example, a 500 to 600 mg supplement taken three times a day. Calcium citrate is the preferred form of calcium.
Vitamin D Supplement
Take 800–1,000 international units (IU) or more of vitamin D per day. This total should be consumed twice day in divided doses of 400 to 500 IU. Along with your calcium supplement, take vitamin D. If you’d rather avoid taking numerous pills, you can take a calcium-vitamin D combo supplement if it has the right amounts.
Vitamin B12 Supplement
Take 500 mcg of vitamin B daily. It can be taken as a tablet, or in sublingual forms placed under the tongue.
Other Supplements
Some patients need additional folic acid or iron supplements, particularly women who are still menstruating. Your dietitian will discuss this with you.
Diet Progression After Bariatric Surgery
You’ll start off with a clear liquid diet right after surgery. When you are released from the hospital and begin your regular diet, you may gradually start including thicker liquids.
You can move to blended and puréed foods two weeks after surgery. To meet your protein needs during this time, you can utilize liquid supplement drinks or powders that are high in protein (more than 20 grams), low in calories (less than 200 calories), or both.
It’s crucial to understand that your stomach will be quite small after surgery—less than 1/4 cup, or around the size of an egg. Additionally, your stomach’s exit point for food is extremely small. This is why it’s crucial to consume any new meal in small amounts—two to three nibbles or sips at a time—and to wait 10 minutes between servings. You will discover more about your tolerance and limit as a result. Your stomach will empty from liquids more quickly than from soft solids.
You can feel sick or hurt if you consume too much or too quickly. Avoid consuming heavy, creamy liquids like gravies, sauces, and ice cream.
Diet in the Hospital
You will receive clear liquids such as juices, Jell-O and broth as your first meal following surgery. Juice and Jell-O are high in sugar content, but your portions will be very small at this stage. Gradually increase the amount you drink at each meal as you can tolerate it.
Diet for the First Two Weeks Post-Surgery
You’ll start incorporating more viscous liquids that are low in fat and sugar and high in protein. (For examples, see the list below.) To meet your protein needs during this time, you can choose liquid supplement drinks or powders that are high in protein and low in calories.
The idea is to drink little amounts that will pass through your pouch with ease. Start with portion sizes of 1 tablespoon and work your way up to 2 tablespoons as tolerated. Drink a quarter cup of liquid at first, then as it feels comfortable, go up to a half cup. You shouldn’t consume more than 400 calories every day.
Additionally, it’s crucial to maintain proper hydration. Each day, consume 1 to 1.5 liters of water or other non-caloric beverages.
Recommended thicker liquids:
- Nonfat or 1% milk, if you can tolerate milk
- Lactose-free or soy-based low-calorie drinks
- Sugar-free pudding
- Sugar-free, nonfat yogurt
- Low-fat cottage cheese
- Blended broth-based soup or other low-fat soups
- Refined hot cereals that are low in fiber, such as cream of rice or cream of wheat. Make them with extra liquid to create a soup-like consistency. Do not eat oatmeal.
- Optional high-protein, low-calorie liquid supplement drinks (drinks containing less than 200 calories and more than 20 grams of protein in an 8- to 11-ounce serving).
To increase your protein intake, add 2 tablespoons non-fat dry milk powder, egg substitute or powered egg, or other protein powder to each 1/2 cup of nonfat or low-fat milk. You can also add these to soups, hot cereal and other thick liquids.
Remember to drink 1 cup of water or other non-caloric fluids between meals. Take a multivitamin supplement every day.
Macronutrients for Bariatric Patients
The parts of food that we eat in big quantities and that give us energy in the form of calories—fat, protein, and carbohydrates—are referred to as macronutrients, or simply “macros.” The majority of our body’s energy comes from macronutrients, and every item we eat contains a certain proportion of each.
Many people who want to get in shape or lose weight count their “macros,” usually according to a ratio. A person aiming to gain muscle and decrease fat, for instance, might consume a ratio of 50% protein, 35% fat, and 15% carbohydrates.
However, I normally advise a bariatric patient to consume 40% protein, 40% fat, and 20% carbohydrates. As a result, 100 grams of protein, 44 grams of fat, and 50 grams of carbohydrates make up 1,000 calories if you are one year post-op.
Protein contains four calories per gram, carbs contain four calories per gram, and fat contains nine calories per gram.
Why You Should Count Your Macros?
Carbohydrates (carbs) can be downright confusing. Some sources claim that eating carbs can hinder weight loss and cause weight gain while others say carbs are an essential part of every diet.
Despite the conflicting advice, the fact is that carbs themselves don’t make you gain weight—excess calories do. So, when it comes to carbs and weight gain, what really matters is the kind of carbs you eat, how much you consume, and what you replace them with if you choose to cut back.
Read on to learn more about carbs and how to enjoy them as a part of a healthy diet without gaining weight.