Gastric bypass surgery offers patients considerable weight loss through restriction (decreasing stomach mass) and malabsorption (limiting caloric absorption). With these significant changes in the body, such as low food intake, it’s possible for patients to feel lethargic, tired, or have low energy.

Dehydration and shortage of macro-/micro-nutrients may result in roux-en-y patients experiencing little to no energy, attentiveness, sudden exhaustion, or weakness.

Nonetheless, patients should not “expect” to feel weary, depressed, or fatigued, and the problem should be addressed immediately.

Emerge Bariatric Vitamins - Vitamins After Weight Loss Surgery - Banner

9 most common culprits of low energy after RNY bypass

1. Not Taking Vitamins

Get lab work done by your primary care physician to uncover any deficiencies that may be the culprit of feeling lethargic.

  • Iron Deficiency – low hemoglobin levels that restore oxygen throughout the body, cells, and lungs.
  • B12 Deficiency – not enough oxygen going to the brain.
  • B1 Deficiency – doesn’t create sufficient energy from carbohydrates. Side effects can cause depression, memory loss, or nausea.

Solution: Take bariatric vitamins that follow the guidelines of the ASMBS (American Society of Metabolic and Bariatric Surgery). These essential, nutrient-rich vitamins are designed explicitly for RNY, Sleeve, and Duodenal Switch Surgery patients who face deficiencies after surgery.

2. Not Getting Enough Calories

Calories, or food, provide the essential nutrition and energy needed to thrive. Keep a calorie count, or food journal, throughout the day. If you are getting less than 1000 calories, chances are you need to increase your intake.

Solution: Ensure your calories come from healthy foods such as lean proteins, vegetables, fruits, legumes, healthy fats, and high-protein grains.

3. Healing Process

Immediately following gastric bypass surgery, the body will be adjusting to healing. It is common to feel sluggish in the first eight weeks after surgery while your body uses more energy for recovery.

Solution: Make sure you are following your bariatric surgeon’s advice to recover and heal correctly.

4. Depression

Depression can be an overwhelming cause of feeling tired, weak, or fatigued after surgery. Understand your emotions and speak with your doctor to find ways to pull through depression. A lot can happen if depression goes untreated or unmanaged.

Solution: Speak with your primary care physician.

5. Not Drinking Enough Water

Water is essential, but it can be challenging to keep up with after all bariatric procedures (especially RNY, gastric sleeve, and duodenal switch surgery). Water is the key to your body’s functionality. It is needed to regulate your body’s systems, including digestion and helping to get rid of toxins. If you are dehydrated, your body will work harder to function, taking up more energy and causing you to feel weak.

Solution: Stay hydrated by drinking a minimum of 64 ounces of water daily.

6. Not Enough Protein

Protein is probably the most essential part of every meal for gastric bypass patients. This is why you should always eat protein first. Eating protein first reduces the odds of being “too full” without finishing the protein part of the meal.

Patients should eat at least 60-90 grams of protein daily. This can be through lean meats, protein products or supplements, dairy, and legumes. Finding ways to incorporate the right amount of protein into your post-op diet can be tricky, but it is 100% required.

Solution: Increase protein intake and log the specific amount of protein into a food journal. Keep track of how you feel as you increase your protein levels. Note any times of the day when fatigue sets in, and start to understand your body’s relationship (cause and effect) with food.

7. Medication

Medication can play a role in feeling drained and can even cause stalls or plateaus after gastric bypass surgery.

Solution: Speak with your primary care physician before adjusting, stopping, or changing any medications.

8. Too Little or Too Much Sleep

Sleep plays a huge role (and one of the most apparent factors) in feeling exhausted after undergoing a weight loss operation. Everyone has a different sleep schedule, patterns, and needs. Not getting enough sleep can build up and have ramifications throughout the day, such as getting too much sleep.

Solution: Start documenting your sleeping patterns. If you feel you are not getting enough sleep, try going to bed a little earlier every night. Make minor adjustments over time. If you are getting too much sleep – you may want to try waking up a little earlier.

It also matters how you wake up in the morning. Sometimes, you need to shower, go for a jog, walk, watch a funny video, or do something that starts the day off right.

9. Exercising Too Much

Another possibility of constantly feeling tired is that you are exercising too much. Without the proper amount of calories to support the exercise, doing it will likely lead to exhaustion and may even stall your weight loss.

Solution: Try doing less intense workouts for longer periods. Or, after an intense workout, do some low-intensity cooldown exercises.

Feeling Tired After Gastric Bypass - Infographic - Weight Loss Surgery - No Energy, Tired, Fatigue, or Weak

Last Tips

To find out why you feel tired after weight loss surgery, try eliminating one of these potential reasons if they apply to you. Regarding health, depression, vitamins, or medication, consult your primary care doctor, bariatric surgeon, and nutritionist before making any alterations.

Food was, at one point, an outlet. Like most addictions, the body takes time to adjust to its new way of life (without the sheer quantity of food as before). Find out why you’re tired after gastric bypass surgery and get your weight loss back on track!

Related Resources

*Remember – None of these reasons or solutions should supplement your doctor’s advice. You should not try making life changes without speaking to your primary care physician.