How to ensure optimal outcomes following Bariatric Surgery 


To ensure positive outcomes of bariatric surgery, you must take ownership in maintaining an optimal nutritional status. Nutritional deficiencies are common in the obese population, which are also common after even the most successful bariatric surgical procedures. Taking ownership means knowing what nutrients should be monitored and preventing/correcting these deficiencies.   


What are specific vitamin (micronutrient) deficiencies seen in the bariatric population?


Despite the high caloric intake seen in the obese population, malnutrition is still common. Interestingly, obesity is typically a chronic pro-inflammatory status, and this increase in inflammation increases the risk of micronutrient malnutrition. The elevated blood level of an obese person's C-Reactive Protein level is a good indicator of the chronic pro-inflammatory response. With this knowledge in hand, it is clear why obese patients considering bariatric surgery must undergo extensive blood analysis of their micronutrients. 


Common micronutrient  deficiencies in the obese population: 


  • Vitamin D (most common) 

  • Magnesium

  • Phosphate

  • Iron

  • Vitamin A

  • Folate

  • Calcium

  • Vitamin B 12

  • Albumin 


Thiamine malabsorption is common following bariatric surgery, leading to thiamine deficiency. This deficiency can lead to excessive bacterial growth in the small intestines.  


A riboflavin deficiency often causes skin irritations and mouth ulcerations.

After bariatric surgery, a folic acid deficiency is commonly observed, which often causes excessive weakness.


Malabsorption and poor food intake following bariatric surgery are the main reasons for Vitamin B12 deficiencies. This deficiency is often demonstrated with weakness and lightheadedness.


Vitamin C is observed frequently following bariatric surgery. Not being able to eat enough fresh fruits and vegetables post-operatively can cause this deficiency. People feel tired, weak, and irritable. Severe deficiency, called scurvy, causes bruising, gum and dental problems, dry hair and skin, and anemia. 


Vitamin D levels impact the strength of your bones; therefore, a deficiency of vitamin D, which is common following bariatric surgery, can put you at risk for bone fractures. It is important to note that the prevalence of vitamin D deficiency  following bariatric surgery, regardless of the type, is very high and should be regularly monitored. 


Final Thoughts


Bariatric surgery is life-saving and life-changing. A decision to undergo surgery is a commitment to lifestyle changes, and these healthy lifestyle changes include a commitment to close monitoring and correcting any micronutrient deficiencies. Adhering to the prescribed fluid, protein, and nutrient intake after bariatric surgery can be overwhelming, especially for the first two to three weeks post-operatively. It is undoubtedly a challenge, and there are options to assist you in assuring you are getting your adequate intake. One option is to explore the possibility of receiving your fluids and nutrients intravenously. To learn more about this possible option, click here



  1. Pre-operative micronutrient deficiencies in patients with severe obesity candidates for bariatric surgery

  2. Vitamin deficiencies and prevention methods after bariatric surgery