Protocol development in integrative medicine is not typically a simple process. Individuals require individualized care, and what works for one patient may not work for another.

To establish these protocols, we first developed a Rating Scale that could be used to discern the rigor of evidence supporting a specific nutrient’s therapeutic effect.

The following protocols were developed using only A through C-quality evidence.

Qualifying studies
Minimum requirements
Systematic review or meta-analysis of human trials
RDBPC human trials
2+ studies and/or 1 study with 50 + subjects
RDBPC human trials
1 study

Bariatric surgery is a transformative intervention for individuals with obesity, necessitating comprehensive postoperative care to ensure optimal recovery and long-term success. One crucial aspect of postoperative management is the consistent, long-term use of dietary supplements to address nutritional deficiencies common in this population. (Sherf-Dagan 2017)

Vitamin and mineral supplementation is a cornerstone in the post-bariatric surgery regimen. The altered gastrointestinal anatomy often leads to decreased absorption of key nutrients, including B vitamins, vitamin D, and iron. (Lupoli 2017) Furthermore, protein supplementation is beneficial for supporting muscle preservation and promoting wound healing. Practitioners should consider appropriate supplements to prevent or correct deficiencies and associated complications. 

Regular monitoring of nutritional status through blood tests is necessary to identify deficiencies promptly and adjust supplement regimens accordingly. (Sherf-Dagan 2017)


Variable based on ingredients and formulation, lifelong daily supplementation is recommended (Heusschen 2021)(Shankar 2010)

  • Bariatric surgery impacts nutrient absorption by altering the anatomy of the digestive system, leading to changes in the way nutrients are absorbed and processed by the body. Micronutrient deficiencies are common following bariatric surgery, necessitating the lifelong daily use of multivitamin supplementation. (Heusschen 2021)(Shankar 2010) Vitamin B12, calcium, vitamin C, vitamin D, vitamin K, thiamine, folic acid, iron, zinc, magnesium, and selenium are among the most common nutrient deficiencies identified in individuals post-bariatric surgery. (Malone 2008)
  • Individuals who didn’t adhere to a standardized multivitamin supplementation (MVS) regimen after laparoscopic Roux-en-Y gastric bypass exhibited a higher number of nutritional deficiencies on average (4.2 vs. 2.9), with a significantly higher number of non-adherent patients having more than five deficiencies. (Ledoux 2014)
Multivitamins in the Fullscript catalog


Variable based on formulation and dependent on the type of surgery performed (Mansoori 2021)

  • B vitamin deficiencies are common post-bariatric surgery, particularly among individuals who have undergone Roux-en-Y gastric bypass. High doses of oral B12 are typically recommended following a Roux-en-Y gastric bypass, whereas lower doses of vitamin B12 may be more appropriate for those receiving a gastric banding or laparoscopic sleeve gastrectomy. (Mansoori 2021
  • Roux-en-Y gastric bypass patients are more likely to experience vitamin B12, while sleeve gastrectomy and gastric banding patients are more likely to experience thiamine deficiency. (Mansoori 2021)
  • A systematic review (SR) showed that oral supplementation doses of ≤15 μg vitamin B12 aren’t sufficient for the prevention of vitamin B12 deficiency in individuals following Roux-en-Y gastric bypass; however, doses of 1,000 μg were shown to be effective. (Mahawar 2018)
  • Three-month supplementation with B vitamins led to a significant 48% increase in serum vitamin B12, a modest elevation in serum folate, and no reduction in blood thiamine- concentrations. (Moore 2014)
B-complex in the Fullscript catalog

Vitamin D

≥ 2,000 IU daily, ongoing with regular nutritional surveillance (Giustina 2023)

  • According to a SR and meta-analysis (MA), the prevalence of preoperative vitamin D insufficiency was 57%, when defined as 25(OH)D < 20 ng/mL, with a median 25(OH)D level of 19.75 ng/mL. After surgery, high-dose oral vitamin D supplementation (≥ 2,000 IU daily) was associated with a lower rate of vitamin D insufficiency and higher 25(OH)D levels. (Giustina 2023)
  • A 2022 SR and MA showed that among patients undergoing bariatric surgery, vitamin D supplementation, particularly at dosages exceeding 2850 IU daily and in those with a body mass index (BMI) greater than 50 kg/m2, modestly improved vitamin D status, prevented an increase in parathyroid hormone (PTH) serum concentration, and had no impact on serum calcium levels. (Mokhtari 2022)
  • Another SR and MA of 12 studies summarized that daily vitamin D supplementation of more than 800 IU was effective in preventing postoperative vitamin D deficiency and improving 25(OH)D levels. (Li 2017)
Vitamin D in the Fullscript catalog


~45–60 mg daily, ongoing with regular nutritional surveillance (Sherf-Dagan 2017)(Mechanick 2013)(Bjørklund 2021

  • According to a SR, iron deficiency affects 16.6% of individuals post-bariatric surgery, specifically 24.5% post-Roux-en-Y gastric bypass and 12.4% post-sleeve gastrectomy. Populations most at risk for iron deficiency post-procedure include premenopausal females and individuals with preoperative iron deficiency. (Enani 2019)
  • Prophylactic ferrous sulfate supplementation has been shown to prevent iron deficiency in menstruating women post-Roux-en-Y gastric bypass. (Brolin 1998)
  • Clinical practice guidelines for patients following bariatric surgery may include supplementation of ferrous sulfate, fumarate, or gluconate, aiming to deliver a daily dose of 150–200 mg of elemental iron. However, ferrous bisglycinate has been shown to effectively increase hemoglobin concentration and reduce gastrointestinal adverse events compared to conventional iron salts such as ferrous sulfate, ferrous fumarate, and ferrous gluconate. (Mechanick 2013)(Fischer 2023)
Iron in the Fullscript catalog


~20 g of protein daily for 6 months minimum (Taselaar 2023)(Al-Shamari 2022)

  • According to an MA, exceeding recommended protein intake after bariatric surgery was found to be associated with greater weight and fat mass loss, particularly in patients consuming ≥ 40 g daily above recommended protein values. (Golzarand 2024)
  • A randomized controlled trial (RCT) suggested that protein supplementation may help prevent muscle loss and protein malnutrition that can result from low protein intake following bariatric surgery. (Al-Shamari 2022)
  • Whey protein supplementation post-surgery exhibited a significant 75% increase in protein intake, resulting in greater body weight loss (1.86 kg) and fat mass loss (2.78 kg). (Gomes 2016)
  • Consider increasing the recommended dose if a plant-based protein source is preferred.
Protein in the Fullscript catalog


1,200–1,500 mg daily through diet and supplementation (Ormanji 2020)(Mechanick 2013)

  • According to the Clinical Practice Guidelines for the Perioperative Nutritional, Metabolic, and Nonsurgical Support of the Bariatric Surgery Patient, it’s recommended that calcium intake be in the range of 1200–1500 mg daily, ideally through a combination of dietary supplements and regular intake of calcium-rich foods such as dairy products, seafood, almonds, and green vegetables. (Mechanick 2013)
  • One study showed that patients with sufficient levels of vitamin D (≥ 30 ng/mL) and adequate calcium intake (> 1,200 mg/day) experienced a significant drop in intestinal calcium absorption from 33% before surgery to 7% after six months of RYGB. (Schafer 2015)
  • Calcium citrate led to a notably higher peak serum calcium concentration compared to the control group. Additionally, it resulted in significantly lower minimum PTH levels. (Tondapu 2009)
Calcium in the Fullscript catalog


The Fullscript Integrative Medical Advisory team has developed or collected these protocols from practitioners and supplier partners to help health care practitioners make decisions when building treatment plans. By adding this protocol to your Fullscript template library, you understand and accept that the recommendations in the protocol are for initial guidance and may not be appropriate for every patient.

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  1. Al-Shamari, S. D., Elsherif, M. A., Hanna, F., Akhal, L. E., Abid, H., & Elhag, W. (2022). The effect of protein supplements on weight loss, body composition, protein status, and micronutrients post laparoscopic sleeve gastrectomy (LSG): A Randomised Controlled Trial (RCT). Annals of Medicine and Surgery, 74
  2. Bjørklund, G., Peana, M., Pivina, L., Doşa, A., Aaseth, J., Semenova, Y., Chirumbolo, S., Medici, S., Dadar, M., & Costea, D. (2021). Iron Deficiency in Obesity and after Bariatric Surgery. Biomolecules, 11(5), 613. 
  3. Brolin, R. E., Gorman, J. H., Gorman, R. C., Petschenik, A. J., Bradley, L. B., Kenler, H. A., & Cody, R. P. (1998). Prophylactic iron supplementation after Roux-en-Y gastric bypass. Archives of Surgery, 133(7). 
  4. Enani, G., Bilgiç, E., Lebedeva, E. V., Delisle, M., Vergis, A., & Hardy, K. (2019). The incidence of iron deficiency anemia post-Roux-en-Y gastric bypass and sleeve gastrectomy: a systematic review. Surgical Endoscopy and Other Interventional Techniques, 34(7), 3002–3010. 
  5. Fischer, J. a. J., Cherian, A. M., Bone, J., & Karakochuk, C. D. (2023). The effects of oral ferrous bisglycinate supplementation on hemoglobin and ferritin concentrations in adults and children: a systematic review and meta-analysis of randomized controlled trials. Nutrition Reviews, 81(8), 904–920.
  6. Giustina, A., Di Filippo, L., Facciorusso, A., Adler, R. A., Binkley, N., Bollerslev, J., Bouillon, R., Freijó, F. C., Cavestro, G. M., Chakhtoura, M., Conte, C., Donini, L. M., Ebeling, P. R., Fassio, A., Frara, S., Gagnon, C., Latella, G., Marcocci, C., Mechanick, J. I., . . . Bilezikian, J. P. (2023). Vitamin D status and supplementation before and after Bariatric Surgery: Recommendations based on a systematic review and meta-analysis. Reviews in Endocrine and Metabolic Disorders (Print), 24(6), 1011–1029. 
  7. Golzarand, M., Toolabi, K., & Mirmiran, P. (2024). The effects of protein intake higher than the recommended value on body composition changes after bariatric surgery: A Meta-Analysis of Randomized Controlled Trials. Clinical Nutrition
  8. Gomes, D. L., Moehlecke, M., Da Silva, F. B. L., Dutra, E. S., Schaan, B. D., & De Carvalho, K. M. B. (2016). Whey Protein Supplementation Enhances Body Fat and Weight Loss in Women Long After Bariatric Surgery: a Randomized Controlled Trial. Obesity Surgery, 27(2), 424–431. 
  9. Heusschen, L., Berendsen, A. M., Cooiman, M. I., Deden, L. N., Hazebroek, E. J., & Aarts, E. O. (2021). Optimizing multivitamin supplementation for sleeve gastrectomy patients. Obesity Surgery, 31(6), 2520–2528. 
  10. Ledoux, S., Calabrese, D., Bogard, C., Dupré, T., Castel, B., Msika, S., Larger, É., & Coupaye, M. (2014). Long-term evolution of nutritional deficiencies after gastric bypass. Annals of Surgery, 259(6), 1104–1110. 
  11. Li, Z., Zhou, X., & Fu, W. (2017). Vitamin D supplementation for the prevention of vitamin D deficiency after bariatric surgery: a systematic review and meta-analysis. European Journal of Clinical Nutrition, 72(8), 1061–1070. 
  12. Lupoli, R., Lembo, E., Saldalamacchia, G., Avola, C. K., Angrisani, L., & Capaldo, B. (2017). Bariatric surgery and long-term nutritional issues. World Journal of Diabetes, 8(11), 464. 
  13. Mahawar, K., Reid, A., Graham, Y., Callejas‐Diaz, L., Parmar, C., Carr, W., Jennings, N., Singhal, R., & Small, P. (2018). Oral Vitamin B12 Supplementation After Roux-en-Y Gastric Bypass: a Systematic Review. Obesity Surgery, 28(7), 1916–1923. 
  14. Malone, M. (2008). Recommended nutritional supplements for bariatric surgery patients. Annals of Pharmacotherapy, 42(12), 1851–1858. 
  15. Mansoori, A. A., Shakoor, H., Ali, H. I., Feehan, J., Dhaheri, A. S. A., Ismail, L. C., Bosevski, M., Apostolopoulos, V., & Stojanovska, L. (2021). The effects of bariatric surgery on vitamin B status and mental health. Nutrients, 13(4), 1383. 
  16. Mechanick, J. I., Youdim, A., Jones, D. B., Garvey, W. T., Hurley, D. L., McMahon, M. M., Heinberg, L. J., Kushner, R. F., Adams, T. D., Shikora, S. A., Dixon, J., & Brethauer, S. A. (2013). Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient—2013 update: Cosponsored by American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery*. Obesity, 21(S1). 
  17. Mokhtari, Z., Hosseini, E., Zaroudi, M., Gibson, D. L., Hekmatdoost, A., Mansourian, M., Salehi‐Abargouei, A., Faghihimani, Z., & Askari, G. (2022). The Effect of Vitamin D Supplementation on Serum 25-Hydroxy Vitamin D in the Patients Undergoing Bariatric Surgery: a Systematic Review and Meta-Analysis of Randomized Clinical Trials. Obesity Surgery, 32(9), 3088–3103. 
  18. Moore, C. E., & Sherman, V. (2014). Effectiveness of B vitamin supplementation following bariatric surgery: Rapid increases of serum vitamin B12. Obesity Surgery, 25(4), 694–699. 
  19. Ormanji, M. S., Rodrigues, F. G., & Heilberg, I. P. (2020). Dietary recommendations for bariatric patients to prevent kidney stone formation. Nutrients, 12(5), 1442. 
  20. Schafer, A. L., Weaver, C. M., Black, D. M., Wheeler, A. L., Chang, H., Szefc, G. V., Stewart, L., Rogers, S. J., Carter, J. T., Posselt, A. M., Shoback, D., & Sellmeyer, D. E. (2015). Intestinal calcium absorption decreases dramatically after gastric bypass surgery despite optimization of vitamin D status. Journal of Bone and Mineral Research, 30(8), 1377–1385. 
  21. Shankar, P., Boylan, M., & Sriram, K. (2010). Micronutrient deficiencies after bariatric surgery. Nutrition, 26(11–12), 1031–1037. 
  22. Sherf-Dagan, S., Goldenshluger, A., Globus, I., Schweiger, C., Kessler, Y., Sandbank, G. K., Ben-Porat, T., & Sinai, T. (2017). Nutritional recommendations for adult bariatric surgery patients: Clinical practice. Advances in Nutrition, 8(2), 382–394. 
  23. Taselaar, A. E., Boes, A. D., De Bruin, R. W. F., Kuijper, M., Van Lancker, K., Van Der Harst, E., & Klaassen, R. A. (2023). PROMISE: effect of protein supplementation on fat-free mass preservation after bariatric surgery, a randomized double-blind placebo-controlled trial. Trials, 24(1). 
  24. Tondapu, P., Provost, D. A., Adams‐Huet, B., Sims, T. L., Chang, C., & Sakhaee, K. (2009). Comparison of the Absorption of Calcium Carbonate and Calcium Citrate after Roux-en-Y Gastric Bypass. Obesity Surgery, 19(9), 1256–1261.