Using Nutrition to Improve Time in rangE (UNITE): A Randomized Clinical Trial with Continuous Glucose Monitoring in People with Type 2 Diabetes Not Taking Insulin
Restricted accessResearch articleFirst published online March, 2026
Using Nutrition to Improve Time in rangE (UNITE): A Randomized Clinical Trial with Continuous Glucose Monitoring in People with Type 2 Diabetes Not Taking Insulin
Preliminary research suggests that continuous glucose monitoring (CGM) can be used to guide food and lifestyle choices. The objective of the Using Nutrition to Improve Time in rangE (UNITE) study was to compare the glycemic and dietary impact of using either a nutrition-focused approach (NFA) or a self-directed approach (SDA) during CGM initiation in people with type 2 diabetes (T2D) not on insulin.
Methods:
UNITE was a 60-day, two-arm, randomized clinical trial. The NFA arm was designed to help participants use CGM data to guide evidenced-based food choices to improve percent time in range with glucose 70–180 mg/dL (TIR70-180) and diet quality, whereas the SDA arm was designed to guide participants to use CGM data in any way that felt useful to them. Changes in outcomes from baseline (Base) to postintervention (Post) were estimated by arm and compared between arms using difference-in-differences; analyses were limited to those with adequate CGM data at Base and Post.
Results:
Adults (NFA: N = 64, SDA: N = 60) with a mean (standard deviation) age of 65.0 (10.3) years, T2D duration of 10.7 (6.5) years, and HbA1c of 7.9% (0.7) participated. There was no differential change in TIR70-180 between arms (P = 0.14), but both arms improved from Base to Post (NFA: 46%–71%, SDA: 55%–71%; within-arm differences both P < 0.001). Time with glucose >250 mg/dL decreased more from Base to Post in the NFA versus the SDA (−14% versus −6%; differential change P = 0.047). NFA participants had several minor, but significant, within-arm changes in dietary intake, and the NFA arm reported significantly more confidence using CGM data than the SDA arm (P < 0.05).
Conclusion:
Changes in mean TIR70-180 did not differ between the NFA and SDA arms; however, both arms experienced significant within-arm improvements, which support the use of CGM to improve glycemia in people with T2D not on insulin.
BergenstalRM. Roadmap to the effective use of continuous glucose monitoring: Innovation, investigation, and implementation. Diabetes Spectr, 2023; 36(4):327–336; doi: 10.2337/dsi23-0005
2.
JacksonMA, AhmannA, ShahVN. Type 2 diabetes and the use of real-time continuous glucose monitoring. Diabetes Technol Ther, 2021; 23(S1):S27–S34; doi: 10.1089/dia.2021.0007
3.
RichardsonKM, JospeMR, BohlenLC, et al.The efficacy of using continuous glucose monitoring as a behaviour change tool in populations with and without diabetes: A systematic review and meta-analysis of randomised controlled trials. Int J Behav Nutr Phys Act, 2024; 21(1):145; doi: 10.1186/s12966-024-01692-6
4.
FranzMJ, MacLeodJ, EvertA, et al.Academy of nutrition and dietetics nutrition practice guideline for type 1 and type 2 diabetes in adults: Systematic review of evidence for medical nutrition therapy effectiveness and recommendations for integration into the nutrition care process. J Acad Nutr Diet, 2017; 117(10):1659–1679; doi: 10.1016/j.jand.2017.03.022
5.
Garcia-MolinaL, Lewis-MikhaelAM, Riquelme-GallegoB, et al.Improving type 2 diabetes mellitus glycaemic control through lifestyle modification implementing diet intervention: A systematic review and meta-analysis. Eur J Nutr, 2020; 59(4):1313–1328; doi: 10.1007/s00394-019-02147-6
6.
KimJ, HurMH. The effects of dietary education interventions on individuals with type 2 diabetes: A systematic review and meta-analysis. Int J Environ Res Public Health, 2021; 18(16):8439; doi: 10.3390/ijerph18168439
7.
KirkpatrickSI, ReedyJ, Krebs-SmithSM, et al.Applications of the healthy eating index for surveillance, epidemiology, and intervention research: Considerations and caveats. J Acad Nutr Diet, 2018; 118(9):1603–1621; doi: 10.1016/j.jand.2018.05.020
8.
MorzeJ, DanielewiczA, HoffmannG, et al.Diet quality as assessed by the healthy eating index, alternate healthy eating index, dietary approaches to stop hypertension score, and health outcomes: A second update of a systematic review and meta-analysis of cohort studies. J Acad Nutr Diet, 2020; 120(12):1998–2031.e15; doi: 10.1016/j.jand.2020.08.076
9.
BrlekA, GregoricM. Diet quality indices and their associations with all-cause mortality, CVD and type 2 diabetes mellitus: An umbrella review. Br J Nutr, 2023; 130(4):709–718; doi: 10.1017/S0007114522003701
10.
AntonioJP, SarmentoRA, de AlmeidaJC. Diet quality and glycemic control in patients with type 2 diabetes. J Acad Nutr Diet, 2019; 119(4):652–658; doi: 10.1016/j.jand.2018.11.006
11.
VinkePC, NavisG, KromhoutD, et al.Associations of diet quality and all-cause mortality across levels of cardiometabolic health and disease: A 7.6-Year prospective analysis from the Dutch lifelines cohort. Diabetes Care, 2021; 44(5):1228–1235; doi: 10.2337/dc20-2709
12.
SanjeeviN, Freeland-GravesJH. Low diet quality is associated with adverse levels of metabolic health markers and clustering of risk factors in adults with type 2 diabetes. J Hum Nutr Diet, 2023; 36(1):31–39; doi: 10.1111/jhn.13020
13.
EvertAB, DennisonM, GardnerCD, et al.Nutrition therapy for adults with diabetes or prediabetes: A consensus report. Diabetes Care, 2019; 42(5):731–754; doi: 10.2337/dci19-0014
14.
American Diabetes Association Professional Practice Committee. 5. Facilitating positive health behaviors and well-being to improve health outcomes: Standards of care in diabetes-2025. Diabetes Care, 2025; 48(Suppl 1):S86–S127; doi: 10.2337/dc25-S005
15.
WillisHJ, JohnsonE, JaKaM. A nutrition-focused approach during continuous glucose monitoring initiation in people with type 2 diabetes: Using a theoretical framework to unite continuous glucose monitoring and food choices. J Diabetes Sci Technol, 2025; 19(5):1400–1406; doi: 10.1177/19322968241247559
16.
ChoeHJ, RheeEJ, WonJC, et al.Effects of patient-driven lifestyle modification using intermittently scanned continuous glucose monitoring in patients with type 2 diabetes: Results from the randomized open-label PDF study. Diabetes Care, 2022; 45(10):2224–2230; doi: 10.2337/dc22-0764
17.
CoxDJ, BantonT, MoncriefM, et al.Glycemic excursion minimization in the management of type 2 diabetes: A novel intervention tested in a randomized clinical trial. BMJ Open Diabetes Res Care, 2020; 8(2):e001795; doi: 10.1136/bmjdrc-2020-001795
18.
CoxDJ, BantonT, MoncriefM, et al.Minimizing Glucose Excursions (GEM) with continuous glucose monitoring in type 2 diabetes: A randomized clinical trial. J Endocr Soc, 2020; 4(11):bvaa118; doi: 10.1210/jendso/bvaa118
19.
MartensT, BeckRW, BaileyR, et al.; MOBILE Study Group. Effect of continuous glucose monitoring on glycemic control in patients with type 2 diabetes treated with basal insulin: A randomized clinical trial. JAMA, 2021; 325(22):2262–2272; doi: 10.1001/jama.2021.7444
20.
AzadbakhtL, FardNR, KarimiM, et al.Effects of the Dietary Approaches to Stop Hypertension (DASH) eating plan on cardiovascular risks among type 2 diabetic patients: A randomized crossover clinical trial. Diabetes Care, 2011; 34(1):55–57; doi: 10.2337/dc10-0676
21.
BattelinoT, DanneT, BergenstalRM, et al.Clinical targets for continuous glucose monitoring data interpretation: Recommendations from the international consensus on time in range. Diabetes Care, 2019; 42(8):1593–1603; doi: 10.2337/dci19-0028
22.
MichieS, van StralenMM, WestR. The behaviour change wheel: A new method for characterising and designing behaviour change interventions. Implement Sci, 2011; 6:42; doi: 10.1186/1748-5908-6-42
23.
MichieS, RichardsonM, JohnstonM, et al.The behavior change technique taxonomy (v1) of 93 hierarchically clustered techniques: Building an international consensus for the reporting of behavior change interventions. Ann Behav Med, 2013; 46(1):81–95; doi: 10.1007/s12160-013-9486-6
24.
BellgAJ, BorrelliB, ResnickB, et al.; Treatment Fidelity Workgroup of the NIH Behavior Change Consortium. Enhancing treatment fidelity in health behavior change studies: Best practices and recommendations from the NIH Behavior Change Consortium. Health Psychol, 2004; 23(5):443–451; doi: 10.1037/0278-6133.23.5.443
25.
BattelinoT, AlexanderCM, AmielSA, et al.Continuous glucose monitoring and metrics for clinical trials: An international consensus statement. Lancet Diabetes Endocrinol, 2023; 11(1):42–57; doi: 10.1016/S2213-8587(22)00319-9
Turner-McGrievyG, HuttoB, BernhartJA, et al.Comparison of the diet ID platform to the Automated Self-Administered 24-hour (ASA24) Dietary assessment tool for assessment of dietary intake. J Am Nutr Assoc, 2022; 41(4):360–382; doi: 10.1080/07315724.2021.1887775
29.
PolonskyWH, FisherL, EarlesJ, et al.Assessing psychosocial distress in diabetes: Development of the diabetes distress scale. Diabetes Care, 2005; 28(3):626–631; doi: 10.2337/diacare.28.3.626
30.
SullivanVK, JohnstonEA, FirestoneMJ, et al.Self-Rated diet quality and cardiometabolic health among U.S. adults, 2011-2018. Am J Prev Med, 2021; 61(4):563–575; doi: 10.1016/j.amepre.2021.04.033
KitabchiAE, UmpierrezGE, MilesJM, et al.Hyperglycemic crises in adult patients with diabetes. Diabetes Care, 2009; 32(7):1335–1343; doi: 10.2337/dc09-9032
33.
MartensTW, WillisHJ, BergenstalRM, et al.A Randomized Controlled Trial Using Continuous Glucose Monitoring to Guide Food Choices and Diabetes Self-Care in People with Type 2 Diabetes not Taking Insulin. Diabetes Technol Ther, 2025; 27(4):261–270; doi: 10.1089/dia.2024.0579, 39757879
34.
AronsonR, BrownRE, ChuL, et al.IMpact of flash glucose Monitoring in pEople with type 2 Diabetes Inadequately controlled with non-insulin Antihyperglycaemic ThErapy (IMMEDIATE): A randomized controlled trial. Diabetes Obes Metab, 2023; 25(4):1024–1031; doi: 10.1111/dom.14949
35.
American Diabetes Association Professional Practice Committee. 7. Diabetes technology: Standards of care in diabetes—2025. Diabetes Care, 2025; 48(Suppl 1):S146–S166; doi: 10.2337/dc25-S007
36.
AjjanRA, BattelinoT, CosX, et al.Continuous glucose monitoring for the routine care of type 2 diabetes mellitus. Nat Rev Endocrinol, 2024; 20(7):426–440; doi: 10.1038/s41574-024-00973-1
37.
UhlS, ChoureA, RouseB, et al.Effectiveness of continuous glucose monitoring on metrics of glycemic control in type 2 diabetes mellitus: A systematic review and meta-analysis of randomized controlled trials. J Clin Endocrinol Metab, 2024; 109(4):1119–1131; doi: 10.1210/clinem/dgad652
38.
FerreiraROM, TrevisanT, PasqualottoE, et al.Continuous glucose monitoring systems in noninsulin-treated people with type 2 diabetes: A systematic review and meta-analysis of randomized controlled trials. Diabetes Technol Ther, 2024; 26(4):252–262; doi: 10.1089/dia.2023.0390
39.
ReavenPD, MacwanS, NewellM, et al.Initiation of continuous glucose monitoring and mortality in type 2 diabetes. Diabetes Technol Ther, 2025; doi: 10.1089/dia.2025.0227
40.
FralickM, ColacciM, OdutayoA, et al.Lowering of hemoglobin A1C and risk of cardiovascular outcomes and all-cause mortality, a meta-regression analysis. J Diabetes Complications, 2020; 34(11):107704; doi: 10.1016/j.jdiacomp.2020.107704
41.
TaylorRM, HaslamRL, HerbertJ, et al.Diet quality and cardiovascular outcomes: A systematic review and meta-analysis of cohort studies. Nutr Diet, 2024; 81(1):35–50; doi: 10.1111/1747-0080.12860
42.
RothbergAE, ArdJD, GudzuneKA, et al.Obesity Management for the Treatment of Type 2 Diabetes. 2024 May 1. In: Diabetes in America (LawrenceJM, CasagrandeSS, HermanWH, et al. eds.). National Institute of Diabetes and Digestive and Kidney Diseases: Bethesda, MD; 2024.
43.
WillisHJ, HendersonMSG, ZibleyLJ, et al.Now I can see it works!” Perspectives on using a nutrition-focused approach when initiating continuous glucose monitoring in people with type 2 diabetes: Qualitative interview study. JMIR Diabetes, 2025; 10:e67636; doi: 10.2196/67636
44.
ClarkTL, PolonskyWH, SorianoEC. The potential impact of continuous glucose monitoring use on diabetes-related attitudes and behaviors in adults with type 2 diabetes: A qualitative investigation of the patient experience. Diabetes Technol Ther, 2024; 26(10):700–708; doi: 10.1089/dia.2023.0612
45.
ShinM, YangY, KangJH, et al.Exploring the initial encounter with continuous glucose monitoring among individuals with type 2 diabetes: A two-week trip. Diabetes Metab Syndr Obes, 2024; 17:3521–3534; doi: 10.2147/DMSO.S466734
46.
FritschiC, KimMJ, SrimoragotM, et al.“Something Tells Me I Can’t Do That No More”: Experiences with real-time glucose and activity monitoring among underserved black women with type 2 diabetes. Sci Diabetes Self Manag Care, 2022; 48(2):78–86; doi: 10.1177/26350106221076042
47.
NataleP, ChenS, ChowCK, et al.Patient experiences of continuous glucose monitoring and sensor-augmented insulin pump therapy for diabetes: A systematic review of qualitative studies. J Diabetes, 2023; 15(12):1048–1069; doi: 10.1111/1753-0407.13454
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