Effect of a Dietary Intervention on Insulin Requirements in Type 1 Diabetes

Diabetes Mellitus, Type 1 Clinical Trial

— T1D  

Official title:

Physicians Committee for Responsible Medicine - A Randomized, Controlled Study of the Effect of a Low-fat, Plant-based Diet on Insulin Requirements in Individuals With Type 1 Diabetes

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT04944316
• Other study ID #: Pro00048903
• Status: Completed
• Phase: N/A
• Start date: January 19, 2022
• Est. completion date: November 9, 2022

Study information

• Verified date: February 2024
• Source: Physicians Committee for Responsible Medicine
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to compare the effects of a low-fat, plant-based dietary intervention and a portion-controlled dietary intervention (compliant with current American Diabetes Association (ADA) guidelines) on the management of type 1 diabetes in adults. The primary outcome measure of this study is insulin requirements (measured as the total daily dose (TDD) of insulin or basal and bolus insulin units injected per day). The study duration is 12 weeks.

Description:

Type 1 diabetes is a chronic autoimmune disorder characterized by loss of β-cell mass and function in the pancreas, leading to reduced secretion of insulin and hyperglycemia. The management of type 1 diabetes requires the administration of exogeneous insulin. Total daily dose (TDD) of insulin, a measure of the total amount of exogeneous insulin utilized per day, can be affected by multiple factors including insulin resistance, carbohydrate intake, body weight, and body composition. While the pathogenesis of type 1 diabetes and type 2 diabetes differ, a low-fat, plant-based diet has been shown to reduce insulin resistance, reduce body weight, improve body composition, and improve glycemic control in individuals with type 2 diabetes. A low-fat, plant-based diet has also been shown to improve β-cell function in individuals who are overweight. This finding is consistent with other research that shows that therapies that reduce body fat, or modify the distribution of body fat, improve β-cell function and glucose homeostasis. To date, a low-fat, plant-based diet has never been adequately tested in adults with type 1 diabetes. The purpose of this study is to compare the effects of low-fat, plant-based dietary intervention and a portion-controlled dietary intervention (compliant with current American Diabetes Association (ADA) guidelines) on insulin requirements in adults with type 1 diabetes.

Using a parallel group design, participants with type 1 diabetes will be randomly assigned to follow a low-fat, plant-based diet or a portion-controlled diet (compliant with current ADA guidelines) for 12 weeks. The principal dependent measures of this study are TDD of insulin, hemoglobin A1c (HbA1c), interstitial fluid glucose levels, and 24-hour carbohydrate: insulin ratio. Secondary and tertiary dependent measures include inflammatory biomarkers, blood lipids, body weight, diet quality, diet acceptability, and medication use.

The investigators hypothesize that both the low-fat, plant-based dietary intervention and the portion-controlled dietary intervention will elicit changes in insulin requirements, HbA1c, variability in interstitial glucose levels, insulin sensitivity, and body weight in participants with type 1 diabetes. The investigators further hypothesize that the low-fat, plant-based dietary intervention will confer a more substantial effect on changes in insulin requirements, HbA1c, insulin sensitivity, variability in interstitial glucose levels, and body weight in participants with type 1 diabetes.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 35
• Est. completion date: November 9, 2022
• Est. primary completion date: November 9, 2022
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion criteria:

1. Type 1 diabetes

2. Men and women = 18 years of age

3. Stable insulin regimen for past 3 months

Exclusion criteria:

1. Type 2 or gestational diabetes

2. Body mass index = 40 kg/m2

3. HbA1c = 12.0%

4. Smoking or drug abuse during the past six months

5. Alcohol consumption of more than 2 drinks per day or the equivalent, episodic increased drinking (e.g., more than 2 drinks per day on weekends), or a history of alcohol abuse or dependency followed by any current use

6. Unstable medical or psychiatric illness

7. Already following a low-fat vegan diet

8. Pregnant or breastfeeding, or plans of pregnancy within the study period

9. Lack of English fluency

10. Unable or unwilling to participate in all components of the study

11. Evidence of an eating disorder

Related Conditions & MeSH terms

• Diabetes Mellitus
• Diabetes Mellitus, Type 1

Intervention

Behavioral:
• Dietary intervention
Low-fat, plant-based diet
• Dietary intervention
Portion-controlled diet (compliant with ADA guidelines)

Locations

Country	Name	City	State
United States	Physicians Committee for Responsible Medicine	Washington	District of Columbia

Sponsors (1)

Lead Sponsor	Collaborator
Physicians Committee for Responsible Medicine

Country where clinical trial is conducted

United States, 

References & Publications (11)

American Diabetes Association. Standards of Medical Care in Diabetes-2018 Abridged for Primary Care Providers. Clin Diabetes. 2018 Jan;36(1):14-37. doi: 10.2337/cd17-0119. No abstract available. — View Citation

American Dietetic Association; Dietitians of Canada. Position of the American Dietetic Association and Dietitians of Canada: Vegetarian diets. J Am Diet Assoc. 2003 Jun;103(6):748-65. doi: 10.1053/jada.2003.50142. — View Citation

Anderson JW, Zeigler JA, Deakins DA, Floore TL, Dillon DW, Wood CL, Oeltgen PR, Whitley RJ. Metabolic effects of high-carbohydrate, high-fiber diets for insulin-dependent diabetic individuals. Am J Clin Nutr. 1991 Nov;54(5):936-43. doi: 10.1093/ajcn/54.5.936. — View Citation

Barnard N, Scialli AR, Bertron P, Hurlock D, Edmonds K. Acceptability of a Therapeutic Low-Fat, Vegan Diet in Premenopausal Women. J Nutr Educ. 2000;32(6):314-319. doi:10.1016/S0022-3182(00)70590-5

Barnard ND, Akhtar A, Nicholson A. Factors that facilitate compliance to lower fat intake. Arch Fam Med. 1995 Feb;4(2):153-8. doi: 10.1001/archfami.4.2.153. — View Citation

Becker MH. The health belief model and personal health behavior. Health Educ Monogr. 1974;2:324-508.

Craig CL, Marshall AL, Sjostrom M, Bauman AE, Booth ML, Ainsworth BE, Pratt M, Ekelund U, Yngve A, Sallis JF, Oja P. International physical activity questionnaire: 12-country reliability and validity. Med Sci Sports Exerc. 2003 Aug;35(8):1381-95. doi: 10.1249/01.MSS.0000078924.61453.FB. — View Citation

Kahleova H, Mari A, Nofrate V, Matoulek M, Kazdova L, Hill M, Pelikanova T. Improvement in beta-cell function after diet-induced weight loss is associated with decrease in pancreatic polypeptide in subjects with type 2 diabetes. J Diabetes Complications. 2012 Sep-Oct;26(5):442-9. doi: 10.1016/j.jdiacomp.2012.05.003. Epub 2012 Jun 4. — View Citation

Mari A, Tura A, Gastaldelli A, Ferrannini E. Assessing insulin secretion by modeling in multiple-meal tests: role of potentiation. Diabetes. 2002 Feb;51 Suppl 1:S221-6. doi: 10.2337/diabetes.51.2007.s221. — View Citation

Pastors JG, Franz MJ, Warshaw H, Daly A, Arnold MS. How effective is medical nutrition therapy in diabetes care? J Am Diet Assoc. 2003 Jul;103(7):827-31. doi: 10.1016/s0002-8223(03)00466-8. No abstract available. — View Citation

Riccardi G, Rivellese AA, Giacco R. Role of glycemic index and glycemic load in the healthy state, in prediabetes, and in diabetes. Am J Clin Nutr. 2008 Jan;87(1):269S-274S. doi: 10.1093/ajcn/87.1.269S. — View Citation

* Note: There are 11 references in all — Click here to view all references

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Medication Use	Participants will be asked to report changes in their medication use.	Change from week 0 to week 12
Other	Diet Quality	Dietary intake will be assessed using 3-day dietary records. Participants will be instructed to record all dietary intake for 3 consecutive days, including 2 weekdays and 1 weekend day. Records will be analyzed using Nutrition Data System for Research software version 2018, developed by the Nutrition Coordinating Center (NCC), University of Minnesota, Minneapolis, MN, US.	Change from week 0 to week 12
Other	Diet Acceptability	The Food Acceptability Questionnaire (FAQ), a self-reported measure, will be implemented to assess the subjective responses (palatability; satisfaction; ease of preparation; financial feasibility; and perceived physical benefits) of participants to their baseline diets and the intervention diet. The FAQ has twelve (12) total questions. Eleven (11) of the questions are scored on a Likert scale (1-7) and one (1) unscored question (physical benefits) will prompt the participant to "check all that apply." A higher FAQ score corresponds with a more positive subjective response.	Change from week 0 to week 12
Primary	Total Insulin Dose	A sum of basal and bolus insulin units (U) injected per day. An average from three (3) days (two (2) workdays and one (1) weekend day) will be utilized.	Change from week 0 to week 12
Primary	Glycemic Control	Hemoglobin A1c (HbA1c), an index of glycemic control, will be utilized.	Change from week 0 to week 12
Primary	Glycemic Variability	Glycemic variability will be assessed through use of a continuous glucose monitoring (CGM) system that will measure the concentration of glucose in the interstitial fluid. Participants will be instructed to wear a CGM (Dexcom g6 Platinum CGM System with an enhanced algorithm, software 505, Dexcom, Inc.) and record its readings at preset increments (after an overnight fast, before each meal, 2 hours after each meal, and before going to bed) daily. Participants will be prompted to submit CGM data to investigators on a weekly basis.	Change from week 0 to week 12
Primary	24-hour Carbohydrate to Insulin Ratio	Calculated as the total number of grams (g) of dietary carbohydrate to total units (U) of insulin administered.	Change from week 0 to week 12
Secondary	Body Weight	Change in body weight measured on a calibrated scale.	Change from week 0 to week 12
Secondary	Concentration of Plasma Lipids	Change in plasma cholesterol & triglycerides.	Change from week 0 to week 12
Secondary	High-sensitivity C-reactive Protein (hs-CRP)	Implemented as a biomarker for absolute cardiovascular disease risk prediction.	Change from week 0 to week 12
Secondary	Tumor necrosis factor - a (TNF-a)	Implemented to assess levels of systemic inflammation.	Change from week 0 to week 12
Secondary	Interleukin (IL) - 1 (IL-1) and interleukin-6 (IL-6)	Implemented to assess levels of systemic inflammation.	Change from week 0 to week 12