Sweet & Sour: Dietary Acid Load in Type 2 Diabetes and Kidney Disease Across Sex and Ethnic Groups

NCT07587918 | Not Yet Recruiting

• 1 other identifier: NL-010928
• Study Type: interventional
• Target: 80
• Locations: 1 country
• Sites: 1

Brief Summary

Chronic kidney disease (CKD) is a common condition and a major global cause of illness and mortality. The most common cause of kidney damage is diabetes, a condition that disrupts metabolism, leading to increased risk of damage to the kidneys and blood vessels. There is evidence suggesting that a diet with high acid load - consisting of acid-forming foods such as meat, cheese, and grain products - may contribute to this damage. People with such a diet often have poorer blood sugar control and more kidney damage. However, it is not yet well understood whether reducing dietary acid load can improve kidney function and diabetes management. Additionally, the role of ethnicity and sex in this process remains insufficiently explored. The goal of this clinical trial is to understand how diet affects kidney function and blood sugar regulation in individuals with diabetes type 2 and chronic kidney disease, as well as to explore the role of sex and ethnicity in these effects. The main questions it aims to answer are: Does a diet with lower acid load (e.g. less meat, cheese, and grain products) improve kidney function and blood sugar regulation in people with diabetes type 2 and chronic kidney disease? Does the effect of diet on kidney function and blood sugar differ between ethnic groups, specifically between White-Dutch and South-Asian Surinamese descent people? Participants will:

• be randomly assigned to follow either a high- or low-acid load diet for 8 weeks;
• Visit the study center four times (including screening)
• Complete food diaries three times per week and keep in regular contact with a dietitian;
• Collect 2x24-hour urine samples and morning feces at each visit ;
• Undergo blood sampling and an oral glucose tolerance test (OGTT).
• Spend a total of 8 hours at the study center (2 visits of 3 hours for OGTT and body composition tests, and 2 visits of 1 hour for additional assessments);
• Have up to 200 ml of blood collected during the study.

Conditions

Type 2 Diabetes; Chronic Kidney Disease

Keywords

sex differences; Ethnic; acid lowering diet; Sweet & Sour; kidney health

Outcome Measures

Primary Outcomes (1)

• Percentage change in urinary albumin-to-creatinine ratio (UACR)

  Log-transformed urinary albumin-to-creatinine ratio (UACR), following an 8-week dietary intervention.

  Change between baseline and 8 weeks

Secondary Outcomes (7)

• Change in estimated glomerular filtration rate (eGFR)

  Change between baseline and 8 weeks

• Change in serum bicarbonate

  Change between baseline and 8 weeks

• Change in urinary citrate

  Change between baseline and 8 weeks

• Glucose response during Oral Glucose Tolerance Test

  Change between baseline and 8 weeks

• Change in glucose variability (MAGE)

  Change between baseline and 8 weeks

Study Arms (2)

High Dietary Acid Load

NO INTERVENTION

This arm will follow their usual diet, which is between DAL\> 50 or \<120mEq H⁺/day (current western diets are generally all high DAL)

Low Dietary Acid Load

EXPERIMENTAL

This arm will follow a DAL lowering diet with the aim to reach \<25mEq H⁺/day

Other: Low Dietary Acid Load

Interventions

Low Dietary Acid Load OTHER

This arm will follow a DAL lowering diet with the aim to reach \<25mEq H⁺/day

Also known as: Low Acid Load Diet

Low Dietary Acid Load

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age \>18 years
• Presence of T2D and CKD stage G1-3a with albuminuria (\>10mg/mmol)
• BMI≥ 25kg/m2 - Use of metformin on a stable dose (i.e. no changes in the last three months)
• Adequate knowledge of the Dutch language to comprehend the provided study information
• If incretin therapy is used, then subject must have used that for a minimum of 6 months before starting with the trial
• Use of ACE inhibitors or angiotensin II receptor blokkers
• Of white European Dutch or South-Asian Surinamese descent

You may not qualify if:

• Use of insulin
• serum bicarbonate \< 20 mmol/L
• Vegetarian diet - Presence of inflammatory bowel disease or other chronic inflammatory disease
• Alcohol consumption of more than 14 units per week in women, or more than 21 units per week in men
• Active malignancy - bariatric or other weight loss surgery in the history
• patients diagnosed with eating disorders (such as bulimia nervosa, anorexia nervosa or binge-eating disorder)
• HbA1c \>9% (75mmol/mol) at screening
• Unmotivated or not able to adhere to a specific diet
• The subject is already currently involved in a clinical trial

Sponsors & Collaborators

• Erasmus Medical Center: lead

Study Sites (1)

Erasmus Medical Center

Rotterdam, Netherlands

Location

Related Links

• Current Clinical Trials of the Rotterdam Kidney Lab and more information about the team and our research

MeSH Terms

Conditions

Diabetes Mellitus, Type 2; Renal Insufficiency, Chronic

Condition Hierarchy (Ancestors)

Diabetes Mellitus; Glucose Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases; Endocrine System Diseases; Renal Insufficiency; Kidney Diseases; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Male Urogenital Diseases; Chronic Disease; Disease Attributes; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Ilias Attaye, Dr.

  Erasmus Medical Center

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Ilias Attaye, Dr.

CONTACT

+31 10 704 0704; i.attaye@erasmusmc.nl

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: Single-centre, non-blinded, randomized controlled 8-week isocaloric dietary intervention trial

Study Record Dates

• First Submitted: April 22, 2026
• First Posted: May 14, 2026
• Study Start (Estimated): June 1, 2026
• Primary Completion (Estimated): June 1, 2028
• Study Completion (Estimated): June 1, 2028
• Last Updated: May 14, 2026

Record last verified: 2026-05

Data Sharing

• IPD Sharing: Will share

Locations

NL (1)