Nutrition & Diabetes www.nature.com/nutd REVIEW ARTICLE OPEN Effectiveness of medical nutrition therapy in adolescents with type 1 diabetes: a systematic review 1,2,7 ✉ Minerva Granado-Casas1,2, Ivan Solà3,4, Marta Hernández 5,6 , Marina Idalia Rojo-López2, Josep Julve1,2 and Didac Mauricio © The Author(s) 2022 BACKGROUND: Medical nutrition therapy (MNT) has an integral role in overall diabetes management. During adolescence, consideration of physiological and psychosocial changes is essential for implementing an optimal diabetes treatment. OBJECTIVES: Our aim was to identify, summarize, and interpret the published literature about MNT in adolescents with type 1 diabetes. METHODS: The Medline (PubMed) and EMBASE databases were searched from January 1959 to December 2021. The inclusion criteria were interventional studies with MNT in adolescents with type 1 diabetes with a disease duration over 1 year, including the following outcomes: dietary intake and daily eating patterns (assessed with validated tools, two or more 24 h dietary recall or 3-day dietary records), the diabetes self-management education and support (DSMES), glycemic control, lipid profile and body mass index (BMI). The exclusion criteria were studies without a control group (except for pre-post studies), the lack of randomization and those 1234567890();,: studies that assessed only a single nutrient, food or meal consumption, as well as reviews, and in-vitro/in-vivo studies. The risk of bias assessment was performed using the Cochrane risk-of-bias tool for randomized trials. A narrative synthesis was performed to present the results. The quality of evidence was assessed with the GRADE guidance. RESULTS: From a total of 5377 records, 12 intervention studies (9 RCT and 3 pre-post intervention studies) were included. The data were assessed in order to perform a meta-analysis; however, the studies were too heterogeneous. The studies showed conflicting results about the effectiveness of MNT on dietary pattern, DSMES, glycemic control, lipid profile and BMI. CONCLUSIONS: Clinical research studies on the effectiveness of MNT in adolescents with type 1 diabetes are scarce. The limited number of studies with a high risk of bias precludes establishing robust conclusions on this issue. Further research is warranted. Nutrition and Diabetes (2022)12:24 ; https://doi.org/10.1038/s41387-022-00201-7 INTRODUCTION maturity are essential for implementing an optimal diabetes The American Diabetes Association (ADA) defines that lifestyle treatment [2]. Moreover, diabetes distress has been shown to be management is a cornerstone of diabetes care and includes positively associated with disordered eating in adolescents with diabetes self-management education and support (DSMES), medical type 1 diabetes [5]. In addition, a poor adherence to nutritional nutrition therapy (MNT), physical activity, smoking cessation recommendations has been observed in children and adolescents counseling, and psychosocial care [1]. For people with type 1 with type 1 diabetes [6]. Having a robust evidence-base regarding diabetes, MNT is a key point in the management of the disease and the effectiveness of MNT is important to inform healthcare is also a component of DSMES. Carbohydrate counting and insulin professionals. The Academy of Nutrition and Dietetics published a management are mainly targeted to enable people with type 1 systematic review to assess the effectiveness of MNT in adults with diabetes to self-manage the disease [2, 3]; furthermore, education type 1 and type 2 diabetes so that healthcare professionals are about how to use fat and protein content to determine insulin knowledgeable about MNT for people with both types of diabetes dosing is recommended to improve glycemic control [2]. In addition, [7, 8]. However, to our knowledge, a systematic review to assess nutritional recommendations based on healthy dietary habits are the effectiveness of MNT in adolescents with type 1 diabetes has included in the MNT of people with diabetes [4]. Nutrition therapy so far not been performed. Adolescents with type 1 diabetes have has an integral role in overall diabetes management, and people particular challenges: attention to family dynamics, developmental with diabetes should be actively engaged in education, self- stages, and physiological changes related with sexual maturity are management, and treatment planning with the healthcare team [1]. essential for implementing an optimal diabetes treatment [2]. During adolescence, attention to family dynamics, develop- Moreover, diabetes distress has been shown to be positively mental stages, and physiological changes related with sexual associated with disordered eating in adolescents with type 1 1 Center for Biomedical Research on Diabetes and Associated Metabolic Diseases (CIBERDEM), Instituto de Salud Carlos III, Barcelona, Spain. 2Department of Endocrinology and Nutrition, Hospital de la Santa Creu i Sant Pau & Sant Pau Biomedical Research Institute (IIB Sant Pau), Barcelona, Spain. 3Institut d’Investigació Biomèdica Sant Pau (IIB Sant Pau), 08041 Barcelona, Spain. 4Center for Biomedical Research on Epidemiology and Public Health (CIBERESP), Instituto de Salud Carlos III, Madrid, Spain. 5Lleida Institute for Biomedical Research Dr. Pifarré Foundation IRBLleida, University of Lleida, Lleida, Spain. 6Department of Endocrinology and Nutrition, University Hospital Arnau de Vilanova, Lleida, Spain. 7Faculty of Medicine, University of Vic (UVIC/UCC), Vic, Spain. ✉email: didacmauricio@gmail.com Received: 19 February 2021 Revised: 23 March 2022 Accepted: 7 April 2022 M. Granado-Casas et al. 2 diabetes [5]. Furthermore, poor adherence to the nutritional statistical methods and adjustment for potential confounders. recommendations has been observed in children and adolescents Effect estimates from included studies was extracted to obtain with type 1 diabetes. For this reason, in this systematic review, we data in terms of risk ratios (with 95% confidence intervals [CIs]) for aimed to identify, summarize, and interpret the published dichotomous outcomes, and mean differences (with 95% CIs) for literature about MNT of adolescents with type 1 diabetes. continuous outcomes. Disagreements were resolved by discussion with the corresponding author (DM). The risk of bias assessment of the RCT was performed using MATERIALS AND METHODS the Cochrane risk-of-bias tool for randomized trials [11]. This tool This systematic review followed the Preferred Reported Items for classifies RCT according to the following domains: the randomi- Systematic Review and Meta-analysis (PRISMA) checklist [9]. The zation process, intended interventions, missing outcome data, protocol was registered with PROSPERO in April 2020 (ID: measurement of the outcome and the selection of the reported CRD42020162314). results. RCT were considered to have a low risk of bias, uncertain and high risk [12]. In addition, non-randomized studies were Search strategy assessed using the Risk of Bias in Non-Randomized Studies - of A systematic review was performed using the MEDLINE (PubMed) Interventions tool (ROBINS-I tool) [13]. This tool classifies the and EMBASE databases searched with a date range from January studies according to seven domains as follows: confounding, 1959 to December 2021. We included all published studies in selection of participants into the study, classification of peer-reviewed journals in the English language. The search interventions, deviations from intended interventions, missing strategy is available in Table S1. Mesh terms were included. data, measurement of outcomes and selection of the reported results. The studies were classified according to the risk of bias as Eligibility criteria follows: low risk (the study was comparable with a well- Studies were included in the systematic review if the study performed randomized trial), moderate (the study provided participants fulfilled the predefined inclusion criteria: studies that sound evidence for a non-randomized study but could not be performed an intervention with MNT in adolescents diagnosed considered comparable with a well-performed randomized trial), with type 1 diabetes with a disease duration of more than 1 year; serious risk (the study had some important problems), critical risk adolescence was defined by the researchers of the included (the study was too problematic to provide any useful evidence studies. Moreover, studies were included if the main outcomes and should not be included in the systematic review), and no were as follows: the dietary intake, which referred to the daily information [14]. eating patterns of an individual (including specific foods, nutrients and calories consumed and relative quantities), estimated using Data synthesis validated food frequency questionnaires, two or more 24 h (h) A summary table with the data extraction was performed dietary recall and a 3-day dietary record, at a minimum; the dietary including the risk of bias. Data analysis was performed with a pattern, which referred to the distribution and selection of daily sensibility analysis of the results taking into account the study food intake, estimated with validated quality dietary indexes; the design, and the risk of bias. A narrative synthesis of the findings of DSMES including knowledge, skills, and abilities necessary for the review was performed according to the outcomes of interest. optimal diabetes self-care, incorporating the needs, goals, and life According to the GRADE guidance [15], the quality of evidence for experiences of the person with diabetes; glycemic control primary outcomes was assessed as an expression of the including hypoglycemia and hyperglycemia defined according confidence in the effect estimates obtained in the review through to the international consensus report; lipid profile and body mass the assessment of risk of bias, directness of evidence, hetero- index (BMI) [10]. geneity and precision of effect estimates. Study selection Eligible study designs were randomized controlled trials (RCT), RESULTS post-hoc analysis of interventional studies and pre-post interven- A total of 5377 records were identified from the two databases tional studies. Exclusion criteria were as follows: interventional search. Following the eligibility criteria, a total of 23 references studies without a control group, except for pre-post interventional reporting on 12 different studies were included in the systematic studies; lack of randomization in controlled trials; studies that only review. From these, 9 were RCT [16–24], 11 were post-hoc studies assessed a single nutrient or consumption of a specific food or from these RCT [25–35], and 3 were pre-post intervention studies meal; the use of non-validated instruments, or the use of only one [36–38]. The PRISMA flow chart is provided in Fig. 1. 24 h dietary recall to estimate dietary intake. Furthermore, the following types of articles were also excluded: reviews; studies Risk of bias of the included studies performed with animals and in-vitro/in-vivo studies; studies A summary of the studies included in the systematic review is without a defined outcome and papers with insufficient data to detailed in Table 1. A total of six randomized trials and the pre- establish conclusions. post intervention studies showed a high risk of bias, while the other three RCT had uncertain risk. The details of the risk of bias Data extraction and risk of bias assessment assessment are described in Tables S2 and S3. Furthermore, a The selection of the studies was performed by three individual summary of included studies and their published reports is researchers. Studies were found to be eligible when two of the described in Table S4. The data were assessed in order to perform independent researchers agreed with the inclusion decision a meta-analysis; however, the studies were too heterogenous in according to the inclusion and exclusion criteria. Nevertheless, in terms of study duration, intervention type and the reported case of a discordant decision, this was discussed with a third outcomes. researcher including a common thorough revision of inclusion/ exclusion criteria of the systematic review. Data extraction was Effect of medical nutrition therapy on the dietary intake and performed by a single researcher and checked by a second diabetes self-management education researcher; this included the following set of variables: first Studies that assessed the effectiveness of MNT for improving author’s surname, year of publication, journal, study design, dietary pattern and DSMES are detailed in Table 2. A total of five country, sample size, study sample characteristics, age of RCT, six post-hoc from RCT and three pre-post intervention studies participants, dietary assessment including instruments used, assessed these interventions. A RCT performed in Poland with a Nutrition and Diabetes (2022)12:24 M. Granado-Casas et al. 3 Identification of studies via databases and registers Records removed before screening: Identification Duplicate records removed Records identified from: (n = 1,225) Databases (n = 5,377) Records marked as ineligible (n = 133) Records removed for other reasons (n = 16) Records screened Records excluded (n = 4,003) (n = 3,917) Reports sought for retrieval Reports not retrieved (n = 86) Screening (n = 7) Reports assessed for eligibility Reports excluded: (n = 79) Cross-over study design (n = 1) Test meals (n = 16) No adolescents (n = 11) No intervention with diet (n = 23) No relevant outcomes (n = 4) Duration of diabetes less than a year (n = 1) Studies included in review (n = 12): Included RCT included in the systematic review (n = 9) Pre-post intervention studies included in the systematic review (n = 3) Reports of included studies (n = 11) Fig. 1 PRISMA flow diagram of the study selection. RCT randomized clinical trial. sample of 151 adolescents with type 1 diabetes found that an differences in reported nutrient intake between an intervention educative intervention with multimedia methods based on the based on a low-glycemic index (low-GI) diet and a traditional ADA recommendations improved the nutrition knowledge and carbohydrate-exchange diet. the dietary quality index of the participants [16]. Nansel et al. [17] In a pre-post intervention study, an intervention based on demonstrated that a family-based behavioral intervention to carbohydrate counting with nutritional recommendations by ADA increase whole plant food intake during an 18-month period was associated with an increase in carbohydrate intake and a increased the adherence to a healthy eating pattern in reduced total fat and protein intake from baseline to 18-months of adolescents with type 1 diabetes compared to usual care (i.e., follow-up [36]. Moreover, MNT also based on the ADA nutritional no dietary advice). Dietary resemblance (i.e., the diet of the child recommendations, reduced the total fat and cholesterol intake, resembles the diet of the parent) was stronger in the intervention and increased the fiber consumption of adolescents in a 6-month group for the outcome of whole plant food density (WPFD) [26], pre-post intervention study [37]. In addition, Lorini et al. [38] while an intervention effect on diet quality was only positive for a observed a reduction of energy intake, total fat, polyunsaturated subgroup of picky eaters [28]. and saturated fatty acids, and an increased intake of carbohydrate A pilot-study performed with a small sample of adolescents and fiber after an intensive MNT based on nutritional guidelines (N = 17) showed that an intervention with an optimized-mixed for the general population. diet for 3 months (based on five meals per day with more than In terms of DSMES, a post-hoc analyses of a RCT performed to 50% of whole grain and low consumption of sweetened assess the relationship between parent attitudes and youth diet beverages) reduced protein intake [20]. Moreover, an intervention quality, described no effect of the intervention on parent attitudes with a flexible low-glycemic diet (based on a list of avoid food or beliefs [30]; however, a higher parent self-efficacy and consumption with low-glycemic index, free meals, whole grains autonomous motivation were positively associated with those and a poor consumption of beverages) reduced the carbohydrate youth with a higher adherence to a WPFD diet. Furthermore, a intake [20]; however, the researchers did not find differences secondary data analysis from this RCT found that a behavioral between both groups of intervention in terms of nutrient intake intervention to improve dietary quality did not increase dis- and Nutritional Quality Index. On the other hand, Hackett et al. ordered eating behaviors in adolescents [29]; nevertheless, a [24] did not find changes in the dietary intake of adolescents and greater adherence to diabetes self-management was associated children that received a MNT based on the ADA nutritional with lower diabetes eating problems in adolescents with type 1 recommendations. Moreover, Gilbertson et al. [35] did not find diabetes [29]. Nutrition and Diabetes (2022)12:24 4 Table 1. Summary of the studies included in the systematic review. Author Sample size Age of participants Study sample Intervention Instruments Outcomes Statistical methods Adjustment for confounders Risk of Bias characteristics Randomized Clinical Trials Dłużniak- N = 70 8–17 years -Treated with Interactive NKS KomPAN HbA1c t-test Not reported High Gołaska intervention with insulin pumps. methods, i.e., Insulin dose analysis of variance et al. [16] interactive -No presence of quiz + Nutrition McNemar’s test methods and chronic diseases multimedia Knowledge Cochran–Mantel–Haenszel test education whose require dietary application BMI N = 81 modifications. intervention with education without interactive methods Nansel N = 66 8–16 years -Daily insulin dose ≥0.5 Behavioral 3-day dietary HEI-2005 t-tests Not reported High et al. [17] intervention units/kg nutrition records WPFD Pearson’s chi-square N = 70 control -HbA1c 6.5–10.0% intervention to HbA1c Permutation test -3 or more injections increase whole daily or use of plant foods insulin pump -At least one clinic visit in the past year -Ability to communicate in English Göksen N = 52 7–18 years -Before the study, Carbohydrate Not reported HbA1c Chi-square test Not reported High et al. [18] intervention traditional exchange- counting Insulin dose t-test N = 32 control based meal plan Lipid profile Mann–Whitney U-test -Glargine/detemir BMI ANOVA test basal-bolus insulin M. Granado-Casas et al. regimens Spiegel N = 33 12–18 years Participants using Carbohydrate 3-day HbA1c t-test Group, age, sex and diabetes High et al. [19] intervention insulin to counting dietary record Spearman correlation duration N = 33 control carbohydrate ratios for 32-item food Fisher’s test at least one meal a frequency day. questionnaire Marquard N=9 6–14 years -Treatment with an Two groups: 4-day dietary Nutritional Wilcoxon signed-rank test Not reported High et al. [20] OMD group intensive conventional - Optimized records Quality Index Mann–Whitney U-test N = 8 low- insulin therapy. mixed diet Macronutrient GI group -No additional dietary - Flexible low- and restrictions. glycemic micronutrient -Exclusion of other index diet composition chronic diseases. HbA1c (%) -No medications that BMI would affect appetite. Gilbertson N = 38 8–13 years -Regular attendance at Comparison 3-day dietary HbA1c Multiple linear Energy intake, group, time-by- High et al. [21] CHOx group the clinic. between the records Hypoglycemia regression models treatment interactions, HbA1c, N = 51 low- -No additional dietary CHOx with low-GI Quality of life Hyperglycemia Spearman’s correlation insulin dose, hyperglycemia and GI group restrictions. questionnaire Insulin dose Logistic regression models hypoglycemia episodes -No immediate family Dietary intake Pearson’s chi-square test members with Quality of life Wilcoxon’s rank-sum test diabetes. -No current medications that would affect the appetite. -Immediate family members with ability to read and write Nutrition and Diabetes (2022)12:24 English. Donaghue N = 12 14–21 years Tanner stage 4–5 MUFA-rich diet: 4-day dietary HbA1c t-test Not reported Uncertain et al. [22] intervention puberty. 43% of fat, 20% records Insulin dose Wilcoxon rank-sum test N = 11 control of MUFA. Lipid profile Regression models Control group: Body weight 30% of fat, 55% of carbohydrate Table 1. continued Author Sample size Age of participants Study sample Intervention Instruments Outcomes Statistical methods Adjustment for confounders Risk of Bias characteristics Pichert N = 69 9–15 years Adolescents MNT 60-item test Nutrition Covariance (inequities Not reported Uncertain et al. [23] participants participating in a Dietary recalls knowledge skills between the groups) diabetes camp Hackett N = 119 families Mean (SD): 11.4 (3.3) Participants attending MNT 3-day dietary Dietary intake Analysis of covariance Age, sex socioeconomic group, Uncertain et al. [24] of the younger children’s diabetic records HbA1c Linear models and duration of diabetes. group, and 12.4 (3.6) clinic. of the older group. Pre-post intervention Marigliano N = 25 7–14 years -Treatment with Carbohydrate 4-day dietary HbA1c t-test Not reported Serious Nutrition and Diabetes (2022)12:24 et al. [36] participants continuous counting with records Insulin dose subcutaneous insulin standard Dietary intake infusion (CSII) for at nutritional BMI least 1 year. education Lipid profile -White race. -No presence of retinopathy or microalbuminuria. -No presence of other autoimmune diseases. Cadario N = 64 13–19 years -Intensive treatment Nutritional Dietary HbA1c Log transformed non- Not reported Serious et al. [37] participants with continuous education records Insulin dose Gaussian data insulin injection or according to the Food Dietary intake Chi-square test multiple daily ADA frequency BMI Fisher’s test injections. recommendations questionnaire Lipid profile McNemar’s test -HbA1c < 7.5 for ANOVA adolescents and Bonferroni test young adults Wilcoxon and Mann- (13–19 years) Whitney U-test -No presence of nephropathy, abnormal liver or thyroid function. -No treatment for dyslipidemia. -No celiac disease. Lorini et al. N = 36 9–21 years -Treated with twice Intensive MNT 3-day dietary Dietary intake t-test Not reported No [38] participants daily administration records Insulin dose information insulin. HbA1c -Visited at pediatric Lipid profile clinic every 2 months. M. Granado-Casas et al. ADA American Diabetes Association, BMI body mass index, CHOx traditional carbohydrate-exchange dietary advice, HbA1c glycated hemoglobin, HEI-2005 Healthy Eating Index-2005, low-GI low-glycemic index diet, MNT medical nutrition therapy, MUFA monounsaturated fatty acids, OMD optimized mixed diet. 5 6 Table 2. Characteristics of the studies that assessed the effectiveness of the Medical Nutrition Therapy to improve dietary pattern and diabetes self-management education and support in adolescents with type 1 diabetes. Author Sample size Age of participants Intervention Outcomes Findings Randomized Clinical Trials Dłużniak- N = 70 intervention with 8–17 years Interactive methods, i.e., quiz + Nutrition Knowledge Nutrition Knowledge: Gołaska interactive methods and multimedia application Index of healthy diet: mean change (95% CI): −2.98 (−5.10;−0.86), p < 0.01 in et al. [16] education (group E) the group C. N = 81 intervention with Total NKS: mean change (95% CI): 3.00 (1.73;4.27), p < 0.001 in the group C, education without interactive and 3.70 (2.56;4.84), p < 0.001 in the group E; p = 0.422 for the intergroup methods (group C) difference after 6 months. Nansel N = 66 intervention 8–16 years Behavioral nutrition intervention to HEI-2005 HEI-2005 (mean (SE) = 64.6 (2.0) intervention group vs. 57.4 (1.6) control et al. [17] N = 70 control increase whole plant foods WPFD group, p = 0.015). WPFD (mean (SE) = 2.2 (0.1) intervention group vs. 1.7 (0.1) control group, p = 0.004) Marquard N = 9 OMD group 6–14 years Two groups: Nutritional OMD group (mean (SD)): et al. [20] N = 8 low-GI group - Optimized mixed diet Quality Index Energy intake (Kcal) = 1767 (300) at baseline and 1532 (386) at follow-up; p = - Flexible low-glycemic index diet Macronutrient and 0.05 micronutrient Carbohydrate (g/day) = 214 (34) at baseline and 191 (62) at follow-up; p = 0.17 composition Total fat (g/day) = 72 (20) at baseline and 58 (15) at follow-up; p = 0.05 Protein (g/day) = 60 (10) at baseline and 57 (12) at follow-up; p = 0.09 Nutritional Quality Index = 79.5 (10.0) at baseline and 75.9 (14.0) at follow-up; p = 0.68 Low-GI group (mean (SD)): Energy intake (Kcal/day) = 1847.0 (281.0) at baseline and 1675.0 (203.0) at follow-up; p = 0.13. Carbohydrate (g/day): 236.0 (46.0) at baseline and 197.0 (31.0) at follow-up; p = 0.04 Total fat (g/day): 70.0 (19.0) at baseline and 70.0 (12.0) at follow-up; p = 0.99 Protein (g/day): 64.0 (16.0) at baseline and 59.0 (13.0) at follow-up; p = 0.17 Nutritional Quality Index = 79.5 (13.0) at baseline and 76.5 (10.0) at follow-up; M. Granado-Casas et al. p = 0.50 Pichert N = 69 participants 9–15 years MNT Nutrition All skills improved (p < 0.01) over time, achieving the primary goal of et al. [23] knowledge skills improving campers’ nutrition knowledge skills. Hackett N = 119 families Mean (SD): 11.4 (3.3) of the MNT Dietary intake Changes in diet were not significant. et al. [24] younger group, and 12.4 (3.6) of the older group. Post-hoc from RCT Lipsky N = 66 intervention 8–16 years Behavioral nutrition intervention to HEI-2005 Associations of parent-child diet quality by treatment assignation (control et al. [26] N = 70 control increase whole plant foods WPFD group as reference): Family meal frequency (β (SE) = 1.57 (1.32) p = 0.23 for aHEI, and 0.21 (0.12), p = 0.08 for WPFD. Diet quality resemblance at final study: HEI (β (SE) = 0.29 (0.11), p = 0.009) of the intervention group WPFD (β (SE) = 0.33 (0.09), p < 0.001) of the intervention group Nansel N = 66 intervention 8–16 years Behavioral nutrition intervention to HEI-2005 The intervention effect on diet quality was positive for picky eaters only et al. [29] N = 70 control increase whole plant foods WPFD (WPFD p < 0.001; HEI p = 0.04). Pickiness subscale of the Child Feeding Questionnaire Eisenberg- N = 42 intervention 8–16 years Behavioral nutrition intervention to Adherence to diabetes Intervention on DEB: Colman N = 48 control increase whole plant foods management tasks β (SE) = 0.00 (0.00), p = 0.84 et al. [30] Disordered eating DEPS-R vs. diabetes management: behaviors (DEB) β (SE) = −0.20 (0.09), p = 0.03 DEPS-R Eisenberg N = 66 intervention 8–16 years Behavioral nutrition intervention to Dietary intake Parent self-efficacy vs. WPFD (β = 0,21, p = 0.02) et al. [31] N = 70 control increase whole plant foods Whole Plant Food Autonomous motivation vs. WPFD (β = 0.17, p = 0.002) Density (WPFD) Nutrition knowledge vs. WPFD (β = 0.01, p = 0.03) Self-Efficacy for Barriers to Healthy Eating vs. WPFD (β = −0.19, p = 0.02) Nutrition and Diabetes (2022)12:24 Healthy Eating Negative Outcomes Expectation vs. WPFD (β = −0.20, p = 0.008) Outcome Expectations Parent positive outcome expectations vs. WPFD (β = 0.07, p = 0.45) for Healthy Eating Controlled motivation vs. WPFD (β = −0.03, p = 0.56) Barriers to Healthy Eating Treatment Self- Regulation Table 2. continued Author Sample size Age of participants Intervention Outcomes Findings Parent Nutrition Knowledge Gilbertson N = 38 CHOx group 8–13 years Comparison between the CHOx with Macronutrient intake Energy intake (MJ/day): et al. [27] N = 51 low-GI group low-GI Carbohydrate food CHOx group vs. low-GI group (mean (SD) = 9.1 (1.7) vs. 9.3 (1.4), respectively). sources Protein (%): Carbohydrate CHOx group vs. low-GI group (mean (SD) = 16.3 (1.9) vs. 16.3 (4.1), distribution of meals respectively). and snacks Total fat (%): CHOx group vs. low-GI group (mean (SD) = 35.3 (5.4) vs. 36.2 (6.3), respectively). Carbohydrate (%): Nutrition and Diabetes (2022)12:24 CHOx group vs. low-GI group (mean (SD) = 48.3 (5.2) vs. 47.7 (6.2), respectively). Sugars (%): CHOx group vs. low-GI group (mean (SD) = 17.3 (5.8) vs. 18.8 (5.2), respectively). Fiber (g/day): CHOx group vs. low-GI group (mean (SD) = 22.4 (4.1) vs. 23.0 (7.2), respectively). No differences in carbohydrate distribution meals between bot groups. Pre-post intervention Marigliano N = 25 participants 7–14 years Carbohydrate counting with standard Dietary intake Energy intake (Kcal) (mean (SD) = 1595 (293.7) at baseline and 1766 (376.9) at et al. [36] nutritional education follow-up, p < 0.01). Carbohydrates (%) (mean (SD) = 53.9 (4.6) at baseline and 56.7 (3.0) at follow- up, p < 0.01). Total fat (%) (mean (SD) = 30.8 (4.3) at baseline and 28.9 (2.7) at follow-up, p < 0.05). Protein (%) (mean (SD) = 15.0 (1.6) at baseline and 13.9 (1.7) at follow-up, p < 0.01). Cadario N = 64 participants 13–19 years Nutritional education according to the Dietary intake Energy intake (Kcal/day) mean (SEM) = 1846.3 (43.8) at baseline and 1570.0 et al. [37] American Diabetes Association (36.6) at follow-up; p value was not significant. recommendations Carbohydrates (g/day) mean (SEM) = 238.2 (6.5) at baseline and 228.1 (5.5) at follow-up; p value was not significant. Total fat (g/day) mean (SEM) = 72.1 (2.5) at baseline and 49.1 (1.8) at follow-up; p < 0.05. Protein (g/day) mean (SEM) = 70.9 (1.5) at baseline and 68.2 (2.1) at follow-up; p value was not significant. Cholesterol (mg/day) mean (SEM) = 265.7 (9.1) at baseline and 94.1 (7.6) at follow-up; p < 0.01. Fiber (g/day) mean (SEM) = 18.5 (0.6) at baseline and 29.3 (1.1) at follow-up; p < 0.01. Lorini et al. N = 36 participants 9–21 years Intensive MNT Dietary intake Energy intake (Kcal/d) (mean (SD)): 2083 (554) vs. 1695 (581), p < 0.001. M. Granado-Casas et al. [38] Total fat (%) (mean (SD)): 38.7 (6.2) vs. 34.3 (6.4), p < 0.01 Protein (%) (mean (SD)): 16.1 (2) vs. 15.4 (2), p was not significant. Carbohydrate (%) (mean (SD)): 44.8 (6.9) vs. 50 (8.2), p < 0.001. Carbohydrate-simple (g) (mean (SD)): 59.2 (23.8) vs. 65.2 (22.2), p < 0.05. Saturated fatty acid (g) (mean (SD)): 34.4 (9.6) vs. 27.3 (7.8), p < 0.001. PUFA (g) (mean (SD)): 12.1 (8.1) vs. 7.9 (3), p < 0.01. Fiber (g) (mean (SD)): 3.2 (1.6) vs. 3.8 (1.9), p < 0.05. BMI body mass index, CI confidence interval, CHOx traditional carbohydrate-exchange dietary advice, HbA1c glycated hemoglobin, HEI-2005 Healthy Eating Index-2005, KomPAN questionnaire for the study of views and dietary habits, low-GI low-glycemic index diet, MNT medical nutrition therapy, NKS Nutrition Knowledge Survey, OMD optimized mixed diet, PUFA polyunsaturated fatty acids, SE standard error, SD standard deviation, WPFD whole plant food density. 7 M. Granado-Casas et al. 8 Effect of medical nutrition therapy on glycemic control effectiveness of MNT in adolescents with type 1 diabetes. In The characteristics of the studies that reported the effect of a addition, the included studies had a small sample size and a high dietary intervention on glycemic control in adolescents with type 1 risk of bias, further contributing to a lack of a robust evidence diabetes are shown in Table 3. Dłużniak-Gołaska et al. [16] found a base. Furthermore, results could not be meta-analyzed because significant reduction in glycated hemoglobin (HbA1c) concentra- the study methods, i.e., duration of the study, intervention type tions after 3 months of treatment with educational materials plus and data, were not comparable. In addition, this review included a interactive methods compared to a control group with educational number of post-hoc analysis and publications derived of a single methods alone. However, HbA1c was not reduced after 6 months trial [17]. from treatment initiation even though the dose of insulin was According to this review, an intervention with MNT based on increased in the intervention group [16]. Hackett et al. [24] found an carbohydrate counting as well as with multimedia methods, whole improved glycemic control in adolescents over age 11 years after plant food intake or nutritional recommendations, has a positive MNT based on nutritional recommendations established in 1989. A impact on the dietary pattern of the adolescents with type 1 RCT performed to assess the effect of an intervention with a WPFD diabetes. These benefits on dietary intake were shown as a did not find differences in HbA1c between the intervention and reduction of total fat and protein intake, an increased adherence control groups [17]; however, a post-hoc analysis of this RCT to a healthy eating pattern, a higher parent-child WPFD diet, and a described that an optimal glycemic control was associated with a high intake of fiber. However, inconsistent results in carbohydrate healthier eating pattern (measured with the Healthy Eating Index- intake were reported, with some studies observing an increased 2005) and a higher adherence to a WPFD diet [34]. In addition, a carbohydrate intake with standard nutritional recommendations, RCT and a pre-post interventional study with MNT based on whereas others found a reduced carbohydrate intake with an carbohydrate counting found a positive effect on the glycemic intervention based on a low-GI diet [20, 36, 38]. These contra- control of adolescents with type 1 diabetes [18, 36]; however, the dictory results could be due to different study methods, type of dose of insulin was not modified with the intervention. A RCT interventions and duration of the study. Moreover, there may have performed to compare a traditional carbohydrate-exchange diet been differences in the study participants, while even the fact of with a low-GI diet found a slight improvement of HbA1c with the participating in an RCT can impact on the lifestyle of the study carbohydrate-exchange diet [21]. On the other hand, Cadario et al. participants, changing their dietary habits and daily routines to [37] did not find changes in glycemic control of the study different extents. Overall, there was a lack of robust evidence participants even though an increased dose of insulin was observed about the effects of MNT on dietary patterns. This is in line with a with a nutritional intervention based on the ADA recommenda- recent systematic review that reported a lack of evidence to assess tions. Furthermore, the other studies did not observe any effect of the effectiveness of technology-based interventions on dietary dietary intervention on glycemic control in adolescents with type 1 habits in children and young people with type 1 diabetes [39]. diabetes [19, 20, 22, 38]. In terms of DSMES, only two post-hoc analyses from a RCT addressed this issue [29, 30]. The authors found that a higher Effect of medical nutrition therapy on lipid profile and body adherence to a WPFD diet was associated with a higher parent mass index self-efficacy and motivation [30]. Furthermore, adolescents with a The effectiveness of MNT on cardiovascular risk factors, i.e., BMI healthy eating diet showed a lower presence of disordered eating and lipid profile, in adolescents with type 1 diabetes is shown in behaviors. A cross-sectional study found that disordered eating Table 4. Only two RCT with their post-hoc studies and one pre- behaviors were associated with a poorer diet quality in post intervention study assessed this issue [16, 18, 27, 32, 38]. adolescents with type 1 diabetes [40]. Of note, another cross- Dłużniak-Gołaska et al. [16] found that trial participants had an sectional study observed that adolescents with a diabetes increased BMI in both the control group (education alone) and duration of 5 years or more had less diabetes care activities intervention groups (education with an interactive intervention compared with individuals with shorter diabetes duration [41]. A with multimedia applications) after 6 months from treatment review performed to assess the effects of carbohydrate-restricted initiation; no between-group differences were observed. On the diets in youth with type 1 diabetes described that the relationship other hand, a post-hoc analyses from a randomized controlled between carbohydrate counting therapies and quality of life had behavioral nutrition intervention trial to assess the associations of still not been adequately assessed among youth with type 1 BMI and body composition with cardiovascular risk factors did not diabetes [42]. However, this review suggested that restrictive find an intervention effect on cardiovascular risk factors after dietary practices may be related with the presence of disordered 18 months from treatment initiation [32]. eating behaviors in adolescents with type 1 diabetes [42]. A In terms of lipid profile, a post-hoc analyses from an RCT systematic review performed to assess the relationship between designed to examine the association of cardiovascular biomarkers psychological factors and diabetes self-management observed with dietary quality diet observed that a healthy eating pattern that a greater adherence to the diet had stronger effects on was not associated with lipid profile [27]. However, the intake of cognitive and emotional variables [43]; these included greater whole grain was inversely related with total cholesterol and high- motivation, dietary self-efficacy, perceived support for autonomy density lipoprotein (HDL) cholesterol; moreover, added sugars and and from family, and stronger beliefs with the effectiveness of saturated fat were positively associated with triglycerides and HDL behavior for diabetes and complications. In addition, diabetes- cholesterol, respectively [27]. On the other hand, a RCT to assess specific disordered eating behaviors are more frequent in girls in the effect of carbohydrate counting on serum lipid levels did not comparison with boys [44, 45]. Insulin under-dosing, intentional find differences between the intervention and control group vomiting, feeling of losing control over food, a short-term weight during 2 years of follow-up [18]; nevertheless, HDL cholesterol was loss (over 6 kg), and body dissatisfaction are disordered eating higher in the carbohydrate counting group during the study behaviors that have been reported to be associated with type 1 follow-up. Finally, Lorini et al. [38] found a reduction of HDL and diabetes in adolescents and youth [46–48]. LDL cholesterol levels after 3 months of intensive MNT in a pre- This systematic review shows different results regarding MNT post intervention study. and glycemic control. Few RCT demonstrated that a dietary intervention based on standard nutritional recommendations or healthy dietary pattern improved glycemic control in adolescents DISCUSSION with type 1 diabetes without changes in insulin dose. However, Only 12 interventional studies were identified in this systematic other clinical trials did not find any effect of the dietary review, demonstrating the paucity of evidence about the intervention on glycemic control. According to the published Nutrition and Diabetes (2022)12:24 Table 3. Characteristics of the studies related to the effectiveness of Medical Nutrition Therapy on glycemic control in adolescents with type 1 diabetes. Author Sample size Age of participants Intervention Outcomes Findings Randomized Clinical Trials Dłużniak-Gołaska N = 70 intervention with 8–17 years Interactive methods, i.e., quiz + HbA1c HbA1c (%): mean change (95% CI): − 0.47 et al. [16] interactive methods and multimedia application Insulin dose (−0.77; −0.17), P < 0.01 in the group E; p education (group E) = 0.038 for the intergroup difference after N = 81 intervention with 3 months. education without However, no significant changes within interactive methods groups after 6 months of treatment. (group C) Insulin dose (U/Kg BW/d): mean change Nutrition and Diabetes (2022)12:24 (95% CI): 0.07 (0.02;0.13), p < 0.05 in the group E. Nansel et al. [17] N = 66 intervention 8–16 years Behavioral nutrition intervention HbA1c HbA1c (%) (mean (SE) = 8.3 (0.1) N = 70 control to increase whole plant foods intervention group vs. 8.2 (0.1) control group); p value was not different between both groups. Göksen et al. [18] N = 52 intervention 7–18 years Carbohydrate counting HbA1c HbA1c (%) (mean (SD) = 8.76 (1.77) for the N = 32 control Insulin dose control and 7.87 (1.38) for the intervention group, p = 0.010). Insulin dose (U/Kg/d) (mean (SD) = 1.02 (0.31) for the controls and 1.01 (0.28) for the intervention group, p = 0.643). Spiegel et al. [19] N = 33 intervention 12–18 years Carbohydrate counting HbA1c Mean (SD) = −0.19 (0.12) for intervention N = 33 control group and −0.08 (0.11) for the control group; p = 0.49. Marquard et al. N = 9 OMD group 6–14 years Two groups: HbA1c OMD group (mean (SD)): [20] N = 8 low-GI group - Optimized mixed diet HbA1c (%) = 7.4 (0.6) at baseline and 7.3 - Flexible low-glycemic index diet (0.5) at follow-up; p = 0.44 Low-GI group (mean (SD)): HbA1c (%) = 7.0 (0.5) at baseline and 6.9 (0.5) at follow-up; p = 0.61 Gilbertson et al. N = 38 CHOx group 8–13 years Comparison between the CHOx HbA1c HbA1c (%): CHOx group vs. low-GI group [21] N = 51 low-GI group with low-GI Incidence of (mean (SD) = 8.6 (1.4) vs. 8.0 (1.0), hypoglycemia and respectively; p = 0.05). M. Granado-Casas et al. hyperglycemia Insulin dose (UI/Kg): CHOx group vs. low- Insulin dose GI group (mean (SD) = 1.0 (0.3) vs. 1.1 (0.3), respectively; p = 0.87). Episodes of hyperglycemia (mean number per month): CHOx group vs. low-GI group (mean (SD) = 16.8 (11.8) vs. 11.2 (9.8), respectively; p = 0.06). Episodes of hypoglycemia (mean number per month): CHOx group vs. low-GI group (mean (SD) = 5.8 (5.5) vs. 6.9 (6.8), respectively; p = 0.37). Donaghue et al. N = 12 intervention 14–21 years MUFA-rich diet: 43% of fat, 20% HbA1c HbA1c (%) (median [IQR] = 8.8 [8.2–9.5] [22] N = 11 control of MUFA. Insulin dose for the intervention group vs. 9.3 Control group: 30% of fat, 55% of [8.0–10.4] for the control group; p = 0.80). carbohydrate Insulin dose (UI/Kg) (mean (SD) = 1.0 (0.2) for the intervention group vs. 0.9 (0.2) for the control group; p = 0.70). 9 10 Table 3. continued Author Sample size Age of participants Intervention Outcomes Findings Hackett et al. [24] N = 119 families Mean (SD): 11.4 (3.3) of the MNT HbA1c In adolescents under 11 years, no changes younger group, and 12.4 in HbA1c were observed. In adolescents (3.6) of the older group. over 11 years, an improved HbA1c was observed (p = 0.02). Post-hoc from RCT Nansel et al. [35] N = 66 intervention 8–16 years Behavioral nutrition intervention HbA1c HbA1c (%) vs. HEI-2005 and WPFD: N = 70 control to increase whole plant foods 1.5-AG β (SE) = 0.003 (0.003), p = 0.36 and −0.03 BG values (0.03), p = 0.27, respectively. MAGE 1.5-AG (µg/mL) vs. HEI-005 and WPFD: (β (SE) = 0.004 (0.008), p = 0.62 and 0.16 (0.08), p = 0.05, respectively). Mean of BG values vs. HEI-2005 and WPFD: β (SE) = −0.41 (0.15), p = 0.005 and −4.35 (1.60), p = 0.006, respectively. MAGE vs. HEI-2005 and WPFD (β (SE) = −0.59 (0.20), p = 0.003 and −6.74 (2.14), p = 0.002, respectively). Pre-post intervention Marigliano et al. N = 25 participants 7–14 years Carbohydrate counting with HbA1c HbA1c (%) (mean (SD) = 8.50 (0.77) at [36] standard nutritional education Insulin dose baseline and 7.92 (0.74) at follow-up, p < 0.001). M. Granado-Casas et al. Insulin dose (IU/Kg/d) (mean (SD) = 0.80 (0.21) at baseline and 0.78 (0.18) at follow- up, p = 0.411). Cadario et al. [37] N = 64 participants 13–19 years Nutritional education according to HbA1c HbA1c (%) mean (SEM) = 8.3 (0.1) at the American Diabetes Association Insulin dose baseline and 8.2 (0.1) at follow-up; p was recommendations not statistically significant. Insulin dose (UI/day): mean (SEM) = 44.8 (1.9) at baseline and 50.6 (1.8) at follow- up; p < 0.001. Lorini et al. [38] N = 36 participants 9–21 years Intensive MNT Insulin dose HbA1c (%) (mean (SD)): 10.6 (2.6) vs. 10.9 HbA1c (2.6); p was not statistically significant. Lipid profile Insulin dose (U/Kg/d) (mean (SD)): 0.98 (0.33) vs. 0.98 (0.34); p was not statistically significant. BG blood glucose, BMI body mass index, CHOx traditional carbohydrate-exchange dietary advice, CI confidence interval, HbA1c glycated hemoglobin, HDL high-density lipoprotein,HEI-2005 Healthy Eating Index- 2005, IQR interquartile range, KomPAN questionnaire for the study of views and dietary habits, LDL low-density lipoprotein, low-GI flexible low-GI dietary advice, MAGE mean amplitude of glycemic excursions, MNT medical nutrition therapy, MUFA monounsaturated fatty acid, NKS Nutrition Knowledge Survey, OMD optimized mixed diet, 1.5-AG 1.5-Anhydroglucitol, SE standard error, SD standard deviation, WPFD whole plant food density. Nutrition and Diabetes (2022)12:24 Table 4. Studies that assessed the effectiveness of the Medical Nutrition Therapy on body mass index and lipid profile in adolescents with type 1 diabetes. Author Sample size Age of Intervention Outcomes Findings participants Randomized Clinical Trials Dłużniak-Gołaska N = 70 intervention with 8–17 years Interactive methods, i.e., quiz BMI SDS-BMI (Kg/m2): mean change (95% CI) after 6 months: et al. [16] interactive methods and + multimedia application 0.14 (0.06;0.21), p < 0.001 in the control group and 0.19 education (group E) (0.09;0.28), p < 0.001 in the intervention group. N = 81 intervention with No differences between both groups after 6 months of education without interactive treatment (p = 0.370). methods (group C) Nutrition and Diabetes (2022)12:24 Göksen et al. [18] N = 52 intervention 7–18 years Carbohydrate counting Lipid profile No association was observed between the treatment N = 32 control assignment and lipid profile. Post-hoc from RCT Sanjeevi et al. [28] N = 66 intervention 8–16 years Behavioral nutrition Lipid profile HEI-2005: N = 70 control intervention to increase whole Intervention vs. control (mean (SD) = 45.33 (12.44) vs. plant foods 46.73 (11.01), p = 0.49; respectively). HEI-2005 vs. Lipid profile (TG, TC, HDL and LDL): no association. Whole grains vs. TC, HDL and LDL (β (SE) = −4.60 (2.05), p = 0.03; −1.98 (0.09), p = 0.046, and −3.42 (1.92), p = 0.08; respectively). Refined grains vs. TG and LDL (β (SE) = −0.02 (0.01), p = 0.08, and 1.72 (0.98), p = 0.08; respectively). Sodium vs. LDL (β (SE) = 5.38 (3.10), p = 0.08). Added sugars (%, Kcal) vs. TG (β (SE) = 0.004 (0.002), p = 0.04). Saturated fat (%, Kcal) vs. HDL (0.34 (0.17), p = 0.04). Lipsky et al. [33] N = 66 intervention 8–16 years Behavioral nutrition BMI Body fat was associated with TG (β (SE) = 0.01 (0.01), p = N = 70 control intervention to increase whole Lipid profile 0.006) and LDL (β (SE) = 0.11 (0.03), p = 0.001), and HDL plant foods (β (SE) = −0.06 (0.00), p = 0.04). BMI was associated with TG (β (SE) = 0.05 (0.01), p < 0.001) and HDL (−0.02 (0.01); p < 0.001). There was no intervention effect on cardiovascular risk factors. M. Granado-Casas et al. Pre-post intervention Lorini et al. [38] N = 36 participants 9–21 years Intensive MNT Lipid profile HDL (mg/dl) (mean (SD)): 50.8 (15.8) vs. 58.7 (14.8), p < 0.01. LDL (mg/dl) (mean (SD)): 117.9 (50.5) vs. 106.8 (53.5), p < 0.05. TC and TG were not different. BMI body mass index, TC total cholesterol, HDL high-density lipoprotein, HEI-2005 Healthy Eating Index-2005, group E experimental group, group C control group, LDL low-density lipoprotein, MNT medical nutrition therapy, SDS-BMI standard deviation score-body mass index, TG triglycerides, WPFD whole plant food density. 11 M. Granado-Casas et al. 12 evidence, adolescents with type 1 diabetes who did not meet 2. American Diabetes Association. 13. Children and Adolescents: Standards of nutritional guidelines showed a poorer glycemic control due to a Medical Care in Diabetes-2020. Diabetes Care. 2020;43:S163–S182. lower adherence to nutritional recommendations [49]. The Diabetes 3. Tascini G, Berioli MG, Cerquiglini L, Santi E, Mancini G, Rogari F, et al. Carbohydrate Control and Complications Trial observed that low adherence to a counting in children and adolescents with type 1 diabetes. Nutrients. 2018;10:1–11. 4. American Diabetes Association. 5. 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However, in a cross-sectional study performed with Bias In Non-randomized Studies of Interventions (ROBINS-I): detailed guidance. adolescent-onset individuals with type 1 diabetes in Japan, a 2016. http://www.riskofbias.info (accessed 23 Jan 2020). poorer lipid profile was associated with western dietary habits 15. Schünemann H, BroZek J, Guyatt G, Oxman A. Handbook for grading the quality [54]. of evidence and the strength of recommendations using the GRADE approach. 2013. https://gdt.gradepro.org/app/handbook/handbook.html. This systematic review provides an overview of the effective- 16. Dłużniak-Gołaska K, Panczyk M, Szypowska A, Sińska B, Szostak-Węgierek D. ness of MNT in adolescents with type 1 diabetes. However, the Interactive nutrition education is more effective in terms of improved levels of search strategy did not include other databases apart from glycated hemoglobin in adolescent patients with poorly controlled type 1 dia- PubMed. This is the first review performed to assess whether MNT betes – A randomized study. Diabetes Metab Syndr Obes Targets Ther. influences in the dietary pattern, diabetes self-management, 2019;12:2619–31. glycemic control and cardiovascular risk factors. The methodology 17. Nansel TR, Laffel LMB, Haynie DL, Mehta SN, Lipsky LM, Volkening LK, et al. of this review following the Cochrane guidelines allows a critical Improving dietary quality in youth with type 1 diabetes: Randomized clinical trial assessment of the current scientific evidence. Moreover, the of a family-based behavioral intervention. Int J Behav Nutr Phys Act. 2015;12:1–11. included studies with different target groups and interventions, 18. Gökşen D, Altinok YA, Özen S, Demir G, Darcan Ş. Effects of carbohydrate counting method on metabolic control in children with type 1 diabetes mellitus. with high and uncertain risk of bias should be considered as a J Clin Res Pediatr Endocrinol. 2014;6:74–8. weakness. 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Glycemic control and variability in association CIBERDEM is an initiative from Instituto de Salud Carlos III (Plan Nacional de I+D+I with body mass index and body composition over 18 months in youth with type and Fondo Europeo de Desarrollo Regional). 1 diabetes. Diabetes Res Clin Pr. 2016;120:97–103. 34. Nansel TR, Lipsky LM, Liu A. Greater diet quality is associated with more optimal glycemic control in a longitudinal study of youth with type 1 diabetes. Am J Clin Nutr. 2016;104:81–7. AUTHOR CONTRIBUTIONS 35. Gilbertson HR, Thorburn AW, Brand-Miller JC, Chondros P, Werther GA. Effect of MG-C, IS, and DM contributed to the conception and design of the study. MG-C, IS, low-glycemic-index dietary advice on dietary quality and food choice in children MH, JJ, M-IR, and DM performed the systematic search and study selection. MG-C with type 1 diabetes. Am J Clin Nutr. 2003;77:83–90. realized the data extraction. MG-C, IS, and DM performed the quality assessment of 36. Marigliano M, Morandi A, Maschio M, Sabbion A, Contreas G, Tomasselli F, et al. studies. MG-C drafted the paper. MG-C, IS, and DM contributed to the discussion of Nutritional education and carbohydrate counting in children with type 1 diabetes the results, review and revision. All authors approved the final paper. treated with continuous subcutaneous insulin infusion: The effects on dietary habits, body composition and glycometabolic control. Acta Diabetol. 2013;50:959–64. 37. Cadario F, Prodam F, Pasqualicchio S, Bellone S, Bonsignori I, Demarchi I, et al. CONFLICT OF INTEREST Lipid profile and nutritional intake in children and adolescents with Type 1 The authors declare no competing interests. diabetes improve after a structured dietician training to a Mediterranean-style diet. J Endocrinol Investig. 2012;35:160–8. 38. Lorini R, Ciriaco O, Salvatoni A, Livieri C, Larizza D, D’Annunzio G. The influence of ADDITIONAL INFORMATION dietary education in diabetic children. Diabetes Res Clin Pr. 1990;9:279–85. Supplementary information The online version contains supplementary material 39. Knox ECL, Quirk H, Glazebrook C, Randell T, Blake H. Impact of technology-based available at https://doi.org/10.1038/s41387-022-00201-7. interventions for children and young people with type 1 diabetes on key dia- betes self-management behaviours and prerequisites: a systematic review. BMC Correspondence and requests for materials should be addressed to Didac Mauricio. Endocr Disord. 2019;19:1–14. 40. Nansel TR, Tse J, Haynie DL, Mehta SN, Laffel LMB. Disordered Eating Behaviors Reprints and permission information is available at http://www.nature.com/ Are Associated with Poorer Diet Quality in Adolescents with Type 1 Diabetes. J reprints Acad Nutr Diet. 2012;112:1810–4. 41. Chao A, Whittemore R, Minges KE, Murphy KM, Grey M. Self-Management in Early Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims Adolescence and Differences by Age at Diagnosis and Duration of Type 1 Dia- in published maps and institutional affiliations. betes. Diabetes Educ. 2014;40:167–77. 42. Gallagher KAS, DeSalvo D, Gregory J, Hilliard ME. Medical and Psychological Considerations for Carbohydrate-Restricted Diets in Youth With Type 1 Diabetes. Curr Diab Rep. 2019;19:1–8. 43. Martinez K, Frazer SF, Dempster M, Hamill A, Fleming H, McCorry NK. Psycholo- Open Access This article is licensed under a Creative Commons gical factors associated with diabetes self-management among adolescents with Attribution 4.0 International License, which permits use, sharing, Type 1 diabetes: A systematic review. J Health Psychol 2018;23:1749–65. adaptation, distribution and reproduction in any medium or format, as long as you give 44. 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Int J Eat Disord. 2014;47:342–52. from the copyright holder. To view a copy of this license, visit http://creativecommons. 46. Cecilia-Costa R, Volkening LK, Laffel LM. Factors associated with disordered eating org/licenses/by/4.0/. behaviours in adolescents with Type 1 diabetes. Diabet Med. 2019;36:1020–7. 47. Troncone A, Cascella C, Chianese A, Zanfardino A, Piscopo A, Borriello A, et al. Body Image Problems and Disordered Eating Behaviors in Italian Adolescents With and © The Author(s) 2022 Nutrition and Diabetes (2022)12:24