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Why Am I So Tired After Bariatric Surgery?

Why Am I So Tired After Bariatric Surgery?

Feeling fatigued after bariatric surgery is not uncommon, especially in the first few months. However, there are a few factors that can increase the amount of fatigue that you experience. Take a look at these 5 causes of fatigue after bariatric surgery. 


Dehydration is one of the top causes of  fatigue after bariatric surgery. All of the surgeries reduce the size of your stomach, making it difficult to consume enough fluid each day. This reason is why it is so valuable to practice not drinking with meals and sipping slowly but consistently throughout the day. If someone goes over an hour without anything to drink, it will feel nearly impossible to consume 64 ounces of fluid.

There are a variety of reusable water bottles that can help with tracking how much water you’re drinking every day and improve its availability. Take a look at a few of the options below!

24oz Stainless Steel Bottle

32oz Motivational Water Bottle

30oz Yeti Tumbler

32oz Camelbak

Protein Goals

Protein is a very important nutrient after bariatric surgery. Depending on your surgery, this will determine your protein goals. Remember, for women with the Sleeve or Gastric Bypass it is important to have 60-80 grams of protein daily. For  men, regardless of surgery choice, the protein recommendation is 80-100 grams of protein daily. For everyone with the Loop or Standard Duodenal Switch surgeries, the recommendation is also 80-100 grams of protein daily.

Protein is important for maintaining your lean muscle mass and healing after surgery. Maintaining your muscle helps keep your strength up while losing weight.

In order to reach these goals, it is important to try to have 3 ounces (20 grams of protein) of protein rich foods at each meal in addition to 1-2 protein supplements each day depending on your goals. Utilizing a kitchen scale is very helpful in portioning foods correctly. Take a look at our article on selecting protein supplements for more information.

It is helpful to make sure you eat protein foods first followed by healthy fats, then vegetables or fruits.

Total Calories

Even though the goal is weight loss, getting enough calories every day is still important. The ultimate goal is to work towards consuming between 800 and 1200 calories each day. It may take a few months to work up to this goal, but eating consistently and listening to your body is helpful.

Keeping track of your nutrition after bariatric surgery is very helpful in making sure you’re reaching your nutrition goals. Take a look at the Baritastic Application and see if you might find this helpful!

If you’re struggling to consume enough calories each day, make sure you are incorporating heart healthy fats 3 times per day. This may look like 1-2 tablespoons of avocado, olives, peanut butter, nuts or olive oil at meals. Some may choose to add 1 tablespoon of peanut butter to their protein supplement to help add a little extra protein and calories in their day.

Additionally, eating 3 meals each day is so important for maintaining consistent energy throughout the day. Even if you are not hungry, set alarms or reminders at meal times to help avoid skipping these meals.

Vitamin and Mineral Deficiency 

Fatigue can also be a sign of vitamin and mineral deficiency. While it is unlikely that you will be able to consume enough calories in those first few months after surgery, you can make sure you are receiving your vitamins by taking them every day as recommended.

Not taking your vitamins after surgery puts you at risk for developing a deficiency which results in fatigue among other symptoms. If you have been taking your vitamins consistently, but are concerned you may be experiencing a vitamin deficiency, please give Central California Surgery a call to speak with a nurse practitioner.

Take a look at Video 13 for a review on the vitamin recommendations after each bariatric surgery.


Right after your surgery, fatigue is very normal. Your body is working really hard to heal and recover from the surgery in addition to not consuming very many calories. While you may be feeling very tired, it is still important to get up and walk about the room or go on short 5-15 minute casual walks throughout the day to promote good circulation and prevent blood clots.

Katie Ott, MS, RD

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