Randomized Control Trial of L-Alanine and Placebo in Fructose Intolerance

Investigation of Supplemental L-alanine in the Management of Dietary Fructose Intolerance: a Double-blind, Randomized Crossover Study

Data suggest that alanine may facilitate the intestinal absorption of fructose in patients with DFI and thereby may decrease GI symptoms.

We hypothesize that the ingestion of supplemental L-alanine along with mixed meals or snacks that contain foods with free fructose or high fructose content will decrease GI symptoms in subjects with dietary fructose intolerance by facilitating intestinal absorption of fructose.

Aim: To investigate the effects of co- administration of equi-molar doses of L-alanine or placebo on the occurrence of GI symptoms in subjects with dietary fructose intolerance, in a randomized, double blind, cross over study.

Methods: We propose to investigate the effects of co-administration of equi-molar doses of L-alanine or placebo on the occurrence of GI symptoms in 70 subjects with dietary fructose intolerance, in a randomized, double blind, cross over study.

Data Analysis: The primary outcome measure will be a comparison of baseline breath sample values and study visit breath sample values. Additionally, we will assess subject-reported occurence and severity of nine gastrointestinal symptoms during the test on a visual analog scale (VAS).

Expected Results: We anticipate that dietary fructose intolerance (DFI) symptoms will improve with ingestion of supplemental L-alanine (along with foods containing free fructose or high fructose content). We additionally expect treatment of DFI with administration of L-alanine powder to be more practical than co-ingestion of alanine-rich foods, and more convenient for patients.

Study Overview

• Status: Terminated
• Conditions: Dietary Fructose Intolerance
• Intervention / Treatment: Dietary supplement: supplemental L-alanine; Dietary supplement: Metamucil

• Study Type: Interventional
• Enrollment (Actual): 15
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • Iowa
    • Iowa City, Iowa, United States, 52246
      • University of Iowa Hospitals and Clinics

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

1. Age between 18-99 years
2. Diagnosis of fructose malabsorption (positive breath test after ingestion of 25 grams of fructose defined as either (a) ≥ 20 ppm rise of breath H2/CH4/both over baseline values or a successive rise of ≥ 5 ppm over baseline and in 3 consecutive breath samples)

Exclusion Criteria:

1. Cognitive impairment or any other inability to provide informed consent
2. Prisoners
3. GI surgery except appendectomy, cholecystectomy, caesarean section, hysterectomy
4. Antibiotics in the previous 6 weeks
5. History of bacterial overgrowth or lactose intolerance
6. Major co-morbid illnesses, including chronic pancreatitis, celiac disease, inflammatory bowel disease, diabetes, scleroderma, pseudo-obstruction syndromes etc.
7. Known food allergies
8. Medication use: opioids, Tegaserod, laxatives, enemas
9. An allergy or intolerance to any fiber supplements or other dietary nutritional supplements such as: psyllium (Metamucil), Maltodextrin, Citric Acid, and methylcellulose (Citrucel).
10. Difficulty swallowing

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: L-alanine; Subjects will consume l-alanine prior to eating fructose-containing foods.	Dietary supplement: supplemental L-alanine; Subjects will consume l-alanine prior to eating fructose-containing foods.
Placebo Comparator: Placebo; Subjects will consume the placebo prior to eating fructose-containing foods.	Dietary supplement: Metamucil; Subjects will consume the placebo prior to eating fructose-containing foods.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
GI symptom score	Change in GI symptom score with alanine & placebo, when compared to the baseline	4 weeks

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Fructose consumption	Estimated daily consumption of fructose during the alanine & placebo phases, when compared to baseline using prospective food diaries	4 weeks
Breath hydrogen and methane	Changes in Breath hydrogen and/or methane values with Alanine and Placebo when compared with baseline	4 weeks
Quality of life (SF-12)	Changes in SF-12 scores between baseline and after alanine and placebo	4 weeks

Collaborators and Investigators

• Sponsor: Augusta University

Study record dates

Study Major Dates

• Study Start: February 1, 2009
• Primary Completion (Actual): December 1, 2011
• Study Completion (Actual): December 1, 2011

Study Registration Dates

• First Submitted: January 31, 2011
• First Submitted That Met QC Criteria: January 31, 2011
• First Posted (Estimate): February 2, 2011

Study Record Updates

• Last Update Posted (Actual): April 15, 2020
• Last Update Submitted That Met QC Criteria: April 13, 2020
• Last Verified: April 1, 2020

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Metabolic Diseases; Genetic Diseases, Inborn; Carbohydrate Metabolism, Inborn Errors; Metabolism, Inborn Errors; Fructose Metabolism, Inborn Errors; Fructose Intolerance; Gastrointestinal Agents; Cathartics; Psyllium
• Other Study ID Numbers: Long Term Fructose