https://orcid.org/0009-0001-9347-6870
Figures
Abstract
Background
Metabolic bariatric surgery (MBS) is a safe, effective treatment for severe obesity and its associated comorbidities. However, adherence to postoperative guidelines, particularly dietary protein intake remains a challenge. This study examined the suitability of the Protein Cards, a protein-focused nutrition education tool developed to support individuals meet their protein requirements during the postoperative diet stages: fluid, purée, soft, and regular.
Methods
An online adapted version of the Suitability Assessment of Materials questionnaire was administered from September 2020 to May 2021. Participants were recruited via convenience sampling and advertisement. Participants rated the rated as “superior”, “adequate” or “not suitable” on content, literacy demand, graphic illustrations, layout and typography, learning stimulation and motivation, and cultural appropriateness, with scores of 2, 1, and 0, respectively.
Results
A total of 437 individuals completed the online survey. Participants were identified as individuals who have undergone MBS (n = 263), caregivers of individuals who completed MBS (n = 68), and/or healthcare providers (including dietitians) specializing in MBS (n = 106). The Protein Cards received an overall “superior” rating of 73.00%. The tool had a high likelihood of use particularly for the soft diet stage (63.99 ± 20.70). Participants preferred the tool be available as a mobile application (63.41 ± 20.41) followed by paper book (59.40 ± 21.95) format.
Citation: Acosta PFC, Heidl AJ, Angeles PM, Farnesi B-C, Alcindor P, Alberga AS, et al. (2025) Evaluation of Protein Cards: A nutrition education tool for metabolic bariatric surgery. PLoS One 20(6): e0319235. https://doi.org/10.1371/journal.pone.0319235
Editor: Athanasios G. Pantelis, Athens Medical Group, Psychiko Clinic, GREECE
Received: January 28, 2025; Accepted: May 7, 2025; Published: June 12, 2025
Copyright: © 2025 Acosta et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Data Availability: The data underlying the results presented in the study are available from the Nutrition and Eating Behaviour Lab website, https://nutritioneatingbehaviour.landfood.ubc.ca/lab-projects/research-study-data/
Funding: This study was supported by funding from TRC University of British Columbia Start-Up Funds (https://www.ubc.ca) and Montreal Children’s Hospital Foundation (https://fondationduchildren.com/en/). There was no additional external funding received for this study.
Competing interests: The authors have declared that no competing interests exist.
Introduction
Severe obesity characterized by a body mass index (BMI) ≥35 kg/m2 affects ~1.9 million Canadian adults, [1] and is projected to double between 2020–2035 [2,3]. This significantly impacts health, overall quality of life, [4] and healthcare costs [5]. While lifestyle interventions remain the first line of treatment for obesity, [6,7] metabolic bariatric surgery (MBS) has been found to be a safe and effective treatment option for severe obesity and its associated comorbidities [8]. Common procedures, such as vertical sleeve gastrectomy and Roux-en-Y gastric bypass, modify the gastrointestinal tract to significantly reduce food intake and capacity to facilitate reduction of excess body weight and lower associated health risks [9]. Notable postoperative benefits include sustained weight reduction, improved cardiometabolic health and health-related quality of life, and remission of type 2 diabetes mellitus [10–14].
The long-term success of MBS remains dependent on commitment to lifestyle changes, particularly, food choices and eating behaviors that significantly influence MBS outcomes [15]. However, non-adherence to dietary guidelines postoperatively is frequently seen in the bariatric population [16–18]. Individuals report feeling overwhelmed [19] and uncertain about food choices [20]. Postoperative dietary guidelines include advancing through the various post-bariatric surgery diet stages: fluid, purée, soft, and regular diets [21,22]. The duration of each stage varies according to the patient’s tolerance, to ensure optimal healing of the gastrointestinal tract, minimize the risk of complications, and facilitate safe adaptation to foods [23].
One of the main nutritional concerns among patients post-MBS is inadequate dietary protein intake [24,25]. Inadequate protein intake has been demonstrated to result in greater loss of fat-free mass [26] and lean mass [27,28] while adequate protein intake postoperatively has been associated with increased satiety, weight loss, and improved body composition [27,29,30]. Current guidelines recommend 35% of total energy intake come from protein [31,32] or a minimum of 60 g/ day up to 1.5 g/kg ideal weight per day [21,24,33,34]. However, studies suggest that protein intake is often inadequate in this population, with a daily protein consumption of approximately 45 g [35,36]. In fact, protein deficiency remains the most severe macronutrient complication post-MBS, largely attributed to avoidance or aversion of protein-rich foods [24,37,38].
The use of nutrition education tools provide comprehensive and accessible information to increase knowledge and facilitate the adoption of healthy nutrition-related behaviors [39]. For these tools to be effective, they need be acceptable, suitable, and targeted to their end-users. However, there is a notable lack of tailored tools to help guide those who have undergone MBS in meeting their postoperative nutritional needs, particularly dietary protein intake. Majority of the materials have reading levels often exceeding what is appropriate for this demographic [40–44]. This is particularly concerning as health literacy was associated with successful weight loss among patients who have undergone MBS [45,46].
As such, the “Protein Cards” tool was developed to facilitate meeting the nutritional needs post-MBS, with emphasis on protein-rich dietary choices. The objective of this study was to evaluate the suitability of a patient nutrition education tool called Protein Cards among individuals who have undergone MBS, their caregivers, and healthcare providers working in MBS.
Materials and methods
Study design
This study was a cross-sectional, online survey conducted from September 2020 to May 2021 to assess perceptions and feedback on the suitability of the Protein Cards. The self-administered survey was designed to be completed within 20–30 minutes. Written informed consent was obtained from all individual participants included in the study. Irrespective of survey completion, participants were eligible to enter a draw for a chance to win a $50 CAD Amazon gift card. The study was approved by The University of British Columbia (Canada) Behavioural Research Ethics Board (ID: H20-01855).
Recruitment and eligibility
Recruitment.
Registered dietitians working in MBS throughout Canada were identified using snowball and convenience sampling to increase feasibility of our recruitment efforts. Registered dietitians were contacted and asked to disseminate the study information (such as recruitment posters) to their patients. To further broaden reach and increase sample size, advertisements through Obesity Canada social media network were also used. The recruitment spanned from June 30, 2020 to April 30, 2021.
Eligibility.
Eligible participants included 1) individuals who have undergone MBS, 2) caregivers of individuals who have undergone MBS or, 3) healthcare providers (such as registered dietitians, nurses, physicians) working in MBS. Participants were excluded if they did not meet the eligibility criteria or if they could not read in English or French and lacked access to a device with Internet connection.
Development of the nutrition education tool: Protein Cards
The development of Protein Cards was inspired by the dietitians at the Centre of Excellence in Adolescence Severe Obesity (CEASO, Montreal Children’s Hospital, Montreal, QC) and co-author Cohen. The tool is available in both English and French and includes 40 easy-to-follow recipes and food items, which were color coded to help guide patients meet their protein requirements for the various post-MBS diet stages: fluid(blue), purée (green), soft (pink), and regular (yellow). This tool focuses on recipes that are protein-rich, with a novel method of quantifying protein. Protein content was denoted in 10 g increments adapted from the carbohydrate counting methodology [47] in the form of a fish icon, which aims to simplify monitoring protein intake without complex calculations. The cards (n = 84) are double-sided: the front displayed the color-coded diet stage, an image of the completed recipe/food item, and protein content per serving while the back provided the recipe or food item along with tips for food substitutions, flavor enhancements, preparation, information on where to source ingredients, and food storage.
Procedures
The self-administered survey was hosted through Qualtrics (Qualtrics International Inc., Seattle, Washington and Provo, Utah, United States), an online survey tool used for academic research at The University of British Columbia (Vancouver, British Columbia, Canada). The survey consisted of two parts: the first section included sociodemographic questions, and the second section utilized an adapted version of the Suitability Assessment of Materials (SAM) questionnaire to evaluate the content and suitability of chosen pages of the Protein Cards, which included the cover page, instruction page, and four representative recipes/ food items corresponding to each diet stage post-surgery.
Measures
Suitability Assessment of Materials (SAM).
The suitability of Protein Cards was evaluated using SAM, a widely used and validated rating tool to assess the appropriateness of health information materials [48–51]. All questions from the 21-item SAM questionnaire were adapted to modify the wording to accommodate varying literacy levels. These questions were classified into six categories: content, literacy demand, graphic illustrations, layout and typography, learning stimulation and motivation, and cultural appropriateness. An additional two questions were included in the survey to understand the usability of the cards [“How likely would you consult the recipe book during the following periods: fluid, purée, soft and regular diet?”] and to determine the preferred delivery format [“How likely would you use the recipe book in the following formats: paper book, electronic book, mobile application, and webpage?”].
Participants were asked to assess the Protein Cards using three possible ratings for each question: “superior”, “adequate”, or “not suitable”, which were assigned point scores of 2, 1, and 0, respectively. The total SAM score was calculated as the sum of earned points divided by the total maximum score of 42. The final SAM scores were reported as percentages, with 70–100% indicating superior material, 40–69% adequate material, and 0–39% not suitable material. Participants rated the usability of the cards across MBS diet stages and the preferred delivery format on a scale of 0–100 (0 = not at all; 100 = highly).
Data analysis
Survey results were obtained in TSV format and all analyses were done with R version 4.3.1 (The R Foundation for Statistical Computing, Vienna, Austria), with p < 0.05 considered statistically significant. Descriptive statistics were used to report participant characteristics and SAM assessment scores by category, as total counts and percentages. Summary statistics of the likelihood of Protein Cards use across MBS diet stages and its preferred method of delivery were reported as means and standard deviations. Analyses were repeated independently for patients, healthcare providers, and caregivers, to gain a better understanding of the participants’ preferences. All data were examined for normality. Chi-square tests or Fisher’s exact tests were used to assess categorical differences in SAM scores across participant groups. The Kruskal –Wallis test was used to compare responses across participant groups for likelihood of use across MBS diet stages and preferred delivery formats.
Results
Participant characteristics
Of the 1,836 surveys received, 437 survey responses were included in the analysis. Participants were excluded if they did not meet inclusion criteria (n = 237), absence of consent (n = 1), missing/ incomplete surveys (n = 177) and data validity, including recurring email and IP addresses (n = 842), inappropriate email address (n = 1), duplicated written responses (n = 33), and completion time under five minutes (n = 103) and participants <19 years (n = 5). Among the 437 participants, 263 (60.18%) were individuals who have undergone MBS, 106 (24.26%) were healthcare providers working in MBS, and 68 (15.56%) were caregivers of patients who had MBS. Majority of participants were female (62.70%) aged between 29–39 (80.92%), self-identified as White (59.17%), completed college/ university educational level (31.65%) and reported an individual annual income of $45,000- $74,999 CAD (44.16%) (Table 1).
SAM questionnaire
The Protein Cards tool was scored as a “superior” postoperative nutrition education tool for MBS, with an overall rating of 73.00%. The six SAM categories received superior mean score values: content (73.90%), literacy demand (72.00%), graphic illustrations (74.50%), layout and typography (71.80%), learning stimulation and motivation (73.50%), and cultural appropriateness (72.10%), which significantly differed by category (p < 0.0001) (Table 2). When examining the data by participant groups, patients significantly gave higher ratings for literacy demand (74.56%, p = 0.009), graphic illustrations (76.62%, p < 0.001), learning stimulation and motivation (75.24%, p = 0.02). Content and cultural appropriateness scores did not significantly differ across participants groups (p = 0.07; p = 0.7, respectively) (Table 3).
Participants reported the highest likelihood of using Protein Cards during the soft diet stage (63.99 ± 20.70) followed by regular diet (63.78 ± 21.05), purée diet (58.58 ± 22.16), and full fluid diet (57.62 ± 21.13), which significantly differed across diet stages (p < 0.001) and participant groups (p < 0.001) (Table 4). When considering the preferred delivery format of Protein Cards, mobile application (63.41 ± 20.41) was found to be the most favored option, with highest ratings among caregivers (68.47 ± 19.51), healthcare providers (64.00 ± 23.93), patients (64.08 ± 19.17), and dietitians (56.44 ± 22.45) (p = 0.007). Preferences for the webpage format did not significantly differ across participants groups. (Table 5).
Discussion
The current study assessed the suitability of Protein Cards, a postoperative patient nutrition education tool in a sample of individuals who have undergone MBS, their caregivers, and healthcare providers working in MBS. Research suggests that there is a lack of diversity of nutrition education materials tailored for the needs of individuals who undergo MBS [42,52]. The focus of Protein Cards is to provide easy-to-follow recipes that are protein-rich to facilitate healthy dietary habits and meet protein requirements during the post-MBS diet stages.
Creating suitable dietary education tools for the intended audience is critical to support the adoption of healthy dietary behavior change. Participants reported Protein Cards to be a “superior” tool with an overall rating of 73.00%, which aligns or exceeds the ratings of other studies that assessed health educational materials [49–51]. The Protein Cards received a superior rating for content- purpose (80.5%), indicating participants’ clear understanding of the tool’s objectives in addressing the dietary needs, particularly protein intake following MBS. Additionally, such a rating suggests the tool’s suitability in supporting optimal transition through the various diet stages and in facilitating the adoption of healthy dietary habits.
Different aspects of nutrition education resources need to be considered to ensure the tool’s suitability. One of those is the tool’s readability. In this study, participants rated the readability of Protein Cards to be between sixth to eighth grade reading level, which was likely due to the use of plain language. Other studies have assessed the readability of MBS patient materials and found them to be overall of poor quality; these materials [40,41,43,44] were above the recommended sixth grade reading level. In a specific examination of patient information publications from the American Society of Metabolic and Bariatric Surgery, Massie et al. (2024) utilized multiple validated assessment tools to evaluate the readability of the publications. Out of the n = 11 publications analyzed, none met the recommended sixth grade reading level, suggesting refinements are needed. Given these findings, there is significant opportunity to enhance the reading grade level of Protein Cards, ensuring the use of clear and plain language to better support patients in meeting their protein needs post-MBS.
Researchers who work in the area of developing nutrition education tools should consider the preferred delivery format to enhance accessibility and user satisfaction of these educational tools. The likelihood of participants utilizing the Protein Cards varied based on delivery format, including paper book, electronic book, mobile application, and webpage. Participants noted a high preference for a mobile application, which has been postulated to reach and gain more engagements among individuals [53]. This is consistent with findings of studies that explored adults’ perspectives on patient health education materials, which have shown a preference for varied types of electronic and paper resources [54,55].
This highlights that the Protein Cards might be more accessible for a diverse sample of patients if they are available in diverse delivery formats.
MBS is a complex process the extends beyond the surgery itself, involving not only the patients, but also their healthcare providers and caregivers to ensure long-term success of dietary management. Our study addresses this by concurrently evaluating the suitability of a nutrition education tool among these groups, with the aim to refine the tool to make it more comprehensive, suitable, and practical for implementation in clinical practice. Research demonstrate that patients can meet nutritional needs with healthy food choices, [56] but experience challenges adhering to postoperative guidance. This suggests that lifelong support is needed, which may lead to improved self-efficacy, a hallmark for behavioral compliance [57]. Additionally, social support from family and friends has been shown to significantly influence dietary management, [57,58] physical and psychological well-being, [58,59] by facilitating effective coping strategies for stressors – a need that becomes more critical as patients adjust to their “new normal” post-MBS [60]. In a study that explored experiences of partners of individuals who have undergone MBS found that they faced various changes, including their level of engagement with the MBS process, such as efforts to access resources available to have a better understanding of the surgical process, and adoption to behavioral changes made by their spouses [61]. While another study highlighted that healthcare providers working in Canadian bariatric surgery program experienced challenges in making clinical decisions on how to best guide patients regarding nutrition pre- and post-surgery [62]. These demonstrated the ongoing need for bariatric resources that are user-friendly, easily accessible, and adaptable to different patient profiles. These findings convey the importance of a patient-centered approach that considers patients, their caregivers, and healthcare providers as integral stakeholders in MBS.
The strengths of this study include a large sample size, and the diverse engagement of stakeholders (patients, caregivers, and healthcare providers) provided a multifaceted evaluation of the Protein Cards. We also used SAM, an evaluation questionnaire that surveys on different aspects of patient education materials. However, this study has limitations, including the lack of data on the type of MBS, which could provide further insights into the tailored nutritional needs of patients. Moreover, recruitment methods used may limit the generalizability of the findings.
In summary, there is a critical need for clear, accessible nutrition education tools tailored for MBS. Our findings demonstrate that the tool we have developed, Protein Cards, is usable and suggests potential benefits for meeting protein requirements across the various stages of post-MBS diet. Participants found the tool to be superior, with a high likelihood of use during these stages. Such tools are essential for supporting patients navigate this complex journey and are pivotal in advancing bariatric care. This can aid in facilitating a smoother transition to a broader range of foods and assist with the emotional and psychological challenges associated with dietary intake post-MBS. Future work will involve refining the tool and pilot testing the tool in clinical settings with individuals undergoing MBS, which will inform a future larger intervention trial aimed at evaluating the efficacy of Protein Cards in helping meet protein recommendations post-MBS.
Acknowledgments
The authors wish to acknowledge all the individuals that contributed to this study: Yolanda Wang and Clare Douglas. Special thanks to Obesity Canada for their role in advertising the study.
References
- 1. Twells LK, Janssen I, Kuk JL. Canadian Adult Obesity Clinical Practice Guidelines: Epidemiology of Adult Obesity. Available from:https://obesitycanada.ca/guidelines/epidemiology.
- 2. Koliaki C, Dalamaga M, Liatis S. Update on the obesity epidemic: after the sudden rise, is the upward trajectory beginning to flatten? Curr Obes Rep. 2023;12(4):514–27. pmid:37779155
- 3. Finkelstein EA, Khavjou OA, Thompson H, Trogdon JG, Pan L, Sherry B, et al. Obesity and severe obesity forecasts through 2030. Am J Prev Med. 2012;42(6):563–70. pmid:22608371
- 4. Chang C-Y, Hung C-K, Chang Y-Y, Tai C-M, Lin J-T, Wang J-D. Health-related quality of life in adult patients with morbid obesity coming for bariatric surgery. Obes Surg. 2010;20(8):1121–7. pmid:18463932
- 5. Butalia S, Luu H, Guigue A, Martins KJB, Williamson T, Klarenbach SW. Health care cost of severe obesity and obesity-related comorbidities: a retrospective cohort study from Alberta, Canada. Obes Res Clin Pract. 2023;17(5):421–7.
- 6. Hassan Y, Head V, Jacob D, Bachmann MO, Diu S, Ford J. Lifestyle interventions for weight loss in adults with severe obesity: a systematic review. Clin Obes. 2016;6(6):395–403. pmid:27788558
- 7. Haywood C, Sumithran P. Treatment of obesity in older persons-A systematic review. Obes Rev. 2019;20(4):588–98. pmid:30645010
- 8. Eisenberg D, Shikora SA, Aarts E, Aminian A, Angrisani L, Cohen RV, et al. 2022 American Society of Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) Indications for Metabolic and Bariatric Surgery. Obes Surg. 2023;33(1):3–14. pmid:36336720
- 9. Nguyen NT, Varela JE. Bariatric surgery for obesity and metabolic disorders: state of the art. Nat Rev Gastroenterol Hepatol. 2017;14(3):160–9. pmid:27899816
- 10. Pipek LZ, Moraes WAF, Nobetani RM, Cortez VS, Condi AS, Taba JV, et al. Surgery is associated with better long-term outcomes than pharmacological treatment for obesity: a systematic review and meta-analysis. Sci Rep. 2024;14(1):9521.
- 11. Arterburn DE, Telem DA, Kushner RF, Courcoulas AP. Benefits and risks of bariatric surgery in adults: a review. JAMA. 2020;324(9):879–87.
- 12. Konttinen H, Sjöholm K, Carlsson LMS, Peltonen M, Svensson PA. Fifteen-year changes in health-related quality of life after bariatric surgery and non-surgical obesity treatment. Int J Obes. 2024;48(10):1447–56.
- 13. Courcoulas AP, Daigle CR, Arterburn DE. Long term outcomes of metabolic/bariatric surgery in adults. BMJ. 2023;383:e071027.
- 14. Affinati AH, Esfandiari NH, Oral EA, Kraftson AT. Bariatric surgery in the treatment of type 2 diabetes. Curr Diab Rep. 2019;19(12):156.
- 15. Cheung HC, Strodl E, Musial J, MacLaughlin HL, Byrnes A, Lewis C-A, et al. Associations between diet composition, dietary pattern, and weight outcomes after bariatric surgery: a systematic review. Int J Obes (Lond). 2023;47(9):764–90. pmid:37407830
- 16. Hood MM, Corsica J, Bradley L, Wilson R, Chirinos DA, Vivo A. Managing severe obesity: understanding and improving treatment adherence in bariatric surgery. J Behav Med. 2016;39(6):1092–103.
- 17. Hood MM, Kelly MC, Feig EH, Webb V, Bradley LE, Corsica J. Measurement of adherence in bariatric surgery: a systematic review. Surg Obes Relat Dis. 2018;14(8):1192–201. pmid:29853195
- 18. Sundgot-Borgen C, Bond DS, Rø Ø, Sniehotta F, Kristinsson J, Kvalem IL. Associations of adherence to physical activity and dietary recommendations with weight recurrence 1–5 years after metabolic and bariatric surgery. Surg Obes Relat Dis. 2024;20(4):383–90.
- 19. Suvarnakar A, Hose BZ, Busog DN, McCloud S, Chao GF, Miller K. Falling short in bariatric surgery: an exploration of key barriers and motivators of attrition. Am J Surg. 2024;115827.
- 20. Tolvanen L, Christenson A, Bonn SE, Surkan PJ, Lagerros YT. Patients’ perspectives on dietary patterns and eating behaviors during weight regain after gastric bypass surgery. Obes Surg. 2023;33(8):2517–26. pmid:37402891
- 21. Mechanick JI, Apovian C, Brethauer S, Garvey WT, Joffe AM, Kim J, et al. Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures - 2019 update: cosponsored by American Association of Clinical Endocrinologists/American College of Endocrinology, The Obesity Society, American Society for Metabolic & Bariatric Surgery, Obesity Medicine Association, and American Society of Anesthesiologists. Surg Obes Relat Dis. 2020;16(2):175–247. pmid:31917200
- 22. Handzlik-Orlik G, Holecki M, Orlik B, Wyleżoł M, Duława J. Nutrition management of the post-bariatric surgery patient. Nutr Clin Pract. 2015;30(3):383–92. pmid:25547336
- 23. Bettini S, Belligoli A, Fabris R, Busetto L. Diet approach before and after bariatric surgery. Rev Endocr Metab Disord. 2020;21(3):297–306. pmid:32734395
- 24. Sherf Dagan S, Goldenshluger A, Globus I, Schweiger C, Kessler Y, Kowen Sandbank G. Nutritional recommendations for adult bariatric surgery patients: clinical practice. Adv Nutr. 2017;8(2):382–94.
- 25. Steenackers N, Gesquiere I, Matthys C. The relevance of dietary protein after bariatric surgery: what do we know? Curr Opin Clin Nutr Metab Care. 2018;21(1):58–63. pmid:29035973
- 26. Sherf Dagan S, Tovim TB, Keidar A, Raziel A, Shibolet O, Zelber-Sagi S. Inadequate protein intake after laparoscopic sleeve gastrectomy surgery is associated with a greater fat free mass loss. Surg Obes Relat Dis. 2017;13(1):101–9. pmid:27521254
- 27. Ito MK, Gonçalves VSS, Faria SLCM, Moizé V, Porporatti AL, Guerra ENS, et al. Effect of protein intake on the protein status and lean mass of post-bariatric surgery patients: a systematic review. Obes Surg. 2017;27(2):502–12. pmid:27844254
- 28. Raftopoulos I, Bernstein B, O’Hara K, Ruby JA, Chhatrala R, Carty J. Protein intake compliance of morbidly obese patients undergoing bariatric surgery and its effect on weight loss and biochemical parameters. Surg Obes Relat Dis. 2011;7(6):733–42.
- 29. van den Broek M, de Heide LJM, Veeger NJGM, van der Wal-Oost AM, van Beek AP. Influence of dietary protein and its amino acid composition on postoperative outcomes after gastric bypass surgery: a systematic review. Nutr Rev. 2016;74(12):749–73. pmid:27864536
- 30. Faria SL, Faria OP, Buffington C, de Almeida Cardeal M, Ito MK. Dietary protein intake and bariatric surgery patients: a review. Obes Surg. 2011;21(11):1798–805. pmid:21590346
- 31. Mechanick JI, Youdim A, Jones DB, Garvey WT, Hurley DL, McMahon MM. 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. Obes Silver Spring Md. 2013;21(Suppl 1):S1–27.
- 32. Moizé VL, Pi-Sunyer X, Mochari H, Vidal J. Nutritional pyramid for post-gastric bypass patients. Obes Surg. 2010;20(8):1133–41. pmid:20401543
- 33. Stenberg E, Dos Reis Falcão LF, O’Kane M, Liem R, Pournaras DJ, Salminen P, et al. Guidelines for perioperative care in bariatric surgery: Enhanced Recovery After Surgery (ERAS) society recommendations: a 2021 update. World J Surg. 2022;46(4):729–51. pmid:34984504
- 34. O’Kane M, Parretti HM, Pinkney J, Welbourn R, Hughes CA, Mok J, et al. British Obesity and Metabolic Surgery Society Guidelines on perioperative and postoperative biochemical monitoring and micronutrient replacement for patients undergoing bariatric surgery-2020 update. Obes Rev. 2020;21(11):e13087. pmid:32743907
- 35. Moize V, Geliebter A, Gluck ME, Yahav E, Lorence M, Colarusso T. Obese patients have inadequate protein intake related to protein intolerance up to 1 year following Roux-en-Y gastric bypass. Obes Surg. 2003;13(1).
- 36. Verger EO, Aron-Wisnewsky J, Dao MC, Kayser BD, Oppert J-M, Bouillot J-L, et al. Micronutrient and protein deficiencies after gastric bypass and sleeve gastrectomy: a 1-year follow-up. Obes Surg. 2016;26(4):785–96. pmid:26205215
- 37. Lupoli R, Lembo E, Saldalamacchia G, Avola CK, Angrisani L, Capaldo B. Bariatric surgery and long-term nutritional issues. World J Diabetes. 2017;8(11):464–74.
- 38. Ben-Porat T, Lahav Y, Cohen TR, Bacon SL, Buch A, Moizé V. Is there a need to reassess protein intake recommendations following metabolic bariatric surgery?. Current Obesity Reports. 2025;14(1):15.
- 39. Contento IR. Nutrition education: linking research, theory, and practice. Asia Pac J Clin Nutr. 2008;17 Suppl 1:176–9. pmid:18296331
- 40. Gutterman SA, Schroeder JN, Jacobson CE, Obeid NR, Suwanabol PA. Examining the accessibility of online patient materials for bariatric surgery. Obes Surg. 2023;33(3):975–7. pmid:36602722
- 41. Lucy AT, Rakestraw SL, Stringer C, Chu D, Grams J, Stahl R, et al. Readability of patient education materials for bariatric surgery. Surg Endosc. 2023;37(8):6519–25. pmid:37277519
- 42. Wang YN, Heidl AJ, Angeles PM, Farnesi B-C, Alberga AS, Cohen TR. Assessment of electronic patient education materials for adolescent bariatric surgery candidates: An environment scan. PEC Innov. 2023;2:100143. pmid:37214509
- 43. Meleo-Erwin Z, Basch C, Fera J, Ethan D, Garcia P. Readability of online patient-based information on bariatric surgery. Health Promot Perspect. 2019;9(2):156–60. pmid:31249804
- 44. Massie PL, Arshad SA, Auyang ED. Readability of American Society of metabolic surgery’s patient information publications. J Surg Res. 2024;293:727–32.
- 45. Mahoney ST, Strassle PD, Farrell TM, Duke MC. Does lower level of education and health literacy affect successful outcomes in bariatric surgery? J Laparoendosc Adv Surg Tech. 2019;29(8):1011–5.
- 46. Erdogdu UE, Cayci HM, Tardu A, Demirci H, Kisakol G, Guclu M. Health literacy and weight loss after bariatric surgery. Obes Surg. 2019;29(12):3948–53. pmid:31290109
- 47. Lopes Souto D, Lopes Rosado E. Use of carb counting in the dietary treatment of diabetes mellitus. Nutr Hosp. 2010;25(1):18–25. pmid:20204251
- 48. Doak CC, Doak LG, Root JH. Teaching patients with low literacy skills. AJN Am J Nurs. 1996;96(12):16M.
- 49. Garnweidner-Holme LM, Dolvik S, Frisvold C, Mosdøl A. Suitability assessment of printed dietary guidelines for pregnant women and parents of infants and toddlers from 7 European countries. J Nutr Educ Behav. 2016;48(2):146–51.e1. pmid:26603301
- 50. Rhee RL, Von Feldt JM, Schumacher HR, Merkel PA. Readability and suitability assessment of patient education materials in rheumatic diseases. Arthritis Care Res (Hoboken). 2013;65(10):1702–6. pmid:23687011
- 51. Tian C, Champlin S, Mackert M, Lazard A, Agrawal D. Readability, suitability, and health content assessment of web-based patient education materials on colorectal cancer screening. Gastrointest Endosc. 2014;80(2):284–90. pmid:24674352
- 52. Yusof NDM, Hamid MRA, Ridhwan MU. Challenges in nutrition education among patients undergoing bariatric surgery: a narrative review. Environ-Behav Proc J. 2024;9(27).
- 53. Messiah SE, Sacher PM, Yudkin J, Ofori A, Qureshi FG, Schneider B, et al. Application and effectiveness of eHealth strategies for metabolic and bariatric surgery patients: a systematic review. Digit Health. 2020;6. pmid:32030193
- 54. Krontoft A. How do patients prefer to receive patient education material about treatment, diagnosis and procedures? —A survey study of patients preferences regarding forms of patient education materials; leaflets, podcasts, and video. Open J Nurs. 2021;11(10):809–27.
- 55. Schooley B, Singh A, Hikmet N, Brookshire R, Patel N. Integrated digital patient education at the bedside for patients with chronic conditions: observational study. JMIR Mhealth Uhealth. 2020;8(12):e22947. pmid:33350961
- 56. Lynch A. “When the honeymoon is over, the real work begins:” Gastric bypass patients’ weight loss trajectories and dietary change experiences. Soc Sci Med. 2016;151:241–9. pmid:26820572
- 57. Li Z, Pan Y, Zhang Y, Qin J, Lei X. Dietary experiences after bariatric surgery in patients with obesity: a qualitative systematic review. Obes Surg. 2022;32(6):2023–34.
- 58. Conceição EM, Fernandes M, de Lourdes M, Pinto-Bastos A, Vaz AR, Ramalho S. Perceived social support before and after bariatric surgery: association with depression, problematic eating behaviors, and weight outcomes. Eat Weight Disord. 2020;25(3):679–92. pmid:30859467
- 59. Agneessens F, Waege H, Lievens J. Diversity in social support by role relations: a typology. Soc Netw. 2006;28(4):427–41.
- 60. Coulman KD, MacKichan F, Blazeby JM, Donovan JL, Owen-Smith A. Patients’ experiences of life after bariatric surgery and follow-up care: a qualitative study. BMJ Open. 2020;10(2):e035013. pmid:32034030
- 61. Wallwork A, Tremblay L, Chi M, Sockalingam S. Exploring partners’ experiences in living with patients who undergo bariatric surgery. Obes Surg. 2017;27(8):1973–81. pmid:28210964
- 62. Farnesi B-C, Kaffash K, Cohen TR, Alberga AS. A qualitative exploration on the needs of health care providers working with adolescents who are undergoing bariatric surgery. Obes Pillars. 2023;6:100067. pmid:37990654