What vitamin deficiencies occur after bariatric (bariatric surgery) surgery?

From the Guidelines

Bariatric surgery patients require lifelong vitamin supplementation to prevent deficiencies, with a recommended daily intake of vitamin D3 ≥ 2,000 IU, as supported by the most recent study 1. After surgery, patients should take a complete multivitamin with minerals twice daily, calcium citrate 1200-1500 mg daily (divided doses), vitamin B12 500-1000 mcg daily (sublingual) or 1000 mcg monthly (intramuscular), and iron 45-60 mg elemental iron daily (separate from calcium by at least 2 hours). The most common deficiencies include vitamin B12, iron, folate, vitamin D, and calcium, which occur due to reduced stomach acid production, decreased absorptive surface area of the intestine, and limited food intake. Sleeve gastrectomy and gastric bypass patients typically require more aggressive supplementation than adjustable gastric band patients. Regular blood monitoring is essential, with labs checked at 3,6, and 12 months post-surgery, then annually thereafter, as recommended by 1. Patients should be aware that symptoms like fatigue, hair loss, and neurological changes may indicate vitamin deficiencies requiring prompt medical attention. Protein intake of 60-80 grams daily is also recommended to prevent muscle loss and support healing, and patients should be counseled on eating behaviors, such as taking small bites, dividing food intake into 4-6 meals, and avoiding high-calorie-dense foods and added sugar, as suggested by 1. Additionally, patients are at risk of developing protein deficiency, and a tailored list of high-protein foods and/or protein supplementation may be necessary, with a focus on solid foods to provide greater satiety, as recommended by 1. It is also important to note that the most recent study 1 recommends high-dose vitamin D supplementation ≥ 2,000 IU/daily to prevent vitamin D insufficiency after bariatric surgery. Overall, the key to preventing vitamin deficiencies after bariatric surgery is lifelong supplementation, regular blood monitoring, and proper eating habits, as supported by the most recent and highest quality studies 1.

Some key points to consider:

• Vitamin D3 supplementation ≥ 2,000 IU/daily is recommended to prevent vitamin D insufficiency after bariatric surgery 1
• Regular blood monitoring is essential to detect vitamin deficiencies early, with labs checked at 3,6, and 12 months post-surgery, then annually thereafter 1
• Patients should be counseled on eating behaviors, such as taking small bites, dividing food intake into 4-6 meals, and avoiding high-calorie-dense foods and added sugar 1
• Protein intake of 60-80 grams daily is recommended to prevent muscle loss and support healing, with a focus on solid foods to provide greater satiety 1
• Patients are at risk of developing protein deficiency, and a tailored list of high-protein foods and/or protein supplementation may be necessary 1

From the Research

Vitamin Deficiencies after Bariatric Surgery

• Bariatric surgery patients are at risk for deficiency of several nutrients, including vitamins B(12), B(1), C, folate, A, D, and K, as well as the trace minerals iron, selenium, zinc, and copper 2.
• The most common vitamin deficiencies after bariatric surgery are:
  • Vitamin D deficiency, which can occur in over 50% of patients preoperatively and can persist postoperatively 3, 4.
  • Vitamin B(12) deficiency, which can occur due to malabsorption 2, 5.
  • Vitamin A deficiency, which can occur due to malabsorption of fat-soluble vitamins 3, 4.
  • Vitamin B(1) deficiency, which can occur due to malabsorption 2, 4.
• The risk of vitamin deficiencies can be reduced by:
  • Providing daily multivitamin and multitrace mineral supplements to all patients scheduled for bariatric surgery 2.
  • Monitoring serum nutrient levels regularly, starting at 3 months after surgery and periodically thereafter 2.
  • Determining the vitamin D status of bariatric surgery candidates and amending it preoperatively 3.
• The clinical significance of vitamin deficiencies after bariatric surgery can be significant, and may include:
  • Maternal and fetal complications, such as severe anemia, congenital abnormalities, low birth weight, and failure to thrive, in pregnant women who have undergone bariatric surgery 2.
  • Delayed wound healing and infection due to the role of vitamin D in re-epithelialization and innate immunity 3.
  • Elevated parathyroid hormone levels, which can occur in up to 45% of patients after bariatric surgery 4.