Effect of Lemon Juice and Apple Cider Vinegar on Postprandial Blood Glucose and Satiety in Healthy Individuals

Summary

This clinical study aims to examine how acidic drinks (lemon juice and apple cider vinegar) affect blood sugar when consumed with a starchy food. The study focuses on healthy individuals and aims to understand whether these drinks can slow the rise in blood sugar after meals and affect feelings of fullness.

The main questions this study aims to answer are:

Do lemon juice or apple cider vinegar lower the rise in blood sugar after a meal? Do these drinks increase feelings of fullness? Do different amounts change their effects?

Researchers will compare lemon juice and apple cider vinegar to see which one is more effective.

Participants will:

Consume white bread in the morning on an empty stomach with one of the following drinks:

Water only Water with lemon juice (50 g or 100 g) Water with apple cider vinegar (10 g or 20 g) Have a one-week break between each test. Have their blood sugar measured at regular intervals for 3 hours after eating. Report their level of fullness using a simple scale.

This study explores whether simple and practical dietary choices can help manage blood sugar levels. The findings may support new, easy-to-apply nutrition strategies for managing diabetes and weight.

Conditions

• Satiety
• Postprandial Glycemia

Interventions

DIETARY_SUPPLEMENT

Apple Cider Vinegar 20 g

Participants will consume 100 g of white bread together with 20 g of apple cider vinegar diluted in water. This intervention evaluates the potential dose-response effect of acetic acid on postprandial glycemic control, including glucose peak, incremental glucose response, and satiety perception over a 180-minute period.

DIETARY_SUPPLEMENT

Control (Water + White Bread)

Participants will consume 100 g of white bread together with plain water (no acidic additive). This condition serves as the control arm for assessing baseline postprandial glycemic response and satiety. Capillary blood glucose will be measured at baseline and at multiple time points up to 180 minutes following consumption. Satiety and appetite sensations will be assessed using a 100-mm visual analog scale (VAS).

DIETARY_SUPPLEMENT

Lemon Juice 50 g

Participants will consume 100 g of white bread together with 50 g of lemon juice diluted in water. This intervention is designed to evaluate the effect of a low-dose acidic beverage (citric acid source) on postprandial blood glucose response and satiety. Capillary blood glucose levels will be measured at predefined time points up to 180 minutes, and subjective appetite sensations will be assessed using a 100-mm VAS.

DIETARY_SUPPLEMENT

Lemon Juice 100 g

Participants will consume 100 g of white bread together with 100 g of lemon juice diluted in water. This condition evaluates the dose-dependent effect of citric acid intake on postprandial glycemic response, glucose peak, and satiety. Serial capillary blood glucose measurements and VAS-based appetite assessments will be conducted over a 180-minute postprandial period.

DIETARY_SUPPLEMENT

Apple Cider Vinegar 10 g

Participants will consume 100 g of white bread together with 10 g of apple cider vinegar diluted in water. This intervention aims to assess the effect of a low-dose acetic acid source on postprandial glucose regulation and satiety. Capillary blood glucose will be measured at multiple time points for 180 minutes, and subjective appetite ratings will be recorded using a visual analog scale.

Sponsors & Collaborators

• Alanya Alaaddin Keykubat University

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

NONE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

35 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-05-01

Primary Completion

2026-07-01

Completion

2026-07-01

Countries

• Turkey (Türkiye)

Study Locations