Carob-Enriched Breads Aid Glycemic Control

Fact checked

By Agata P. | Updated: Nov 29, 2023

Carob-Enriched Breads Aid Glycemic Control
General Information
  • 01 Jul 2018
  • Greece
  • Agricultural University of Athens
  • Papakonstantinou, E. et al
  • Clinical trial
  • 10 adults
  • 8 weeks

In recent years, nutritious flours that serve as wheat substitutes are in high demand. They are not only valuable to diabetics who are instructed to steer clear of foods with high glycemic index, but also to those wanting to prevent diseases and add more nutrients into their meals.

In terms of suitable low-glycemic ingredients, several studies point to carob.1,2 This Mediterranean native is known for its astounding amounts of polyphenol-rich fiber, recognized for its role in lowering glycemic response and increasing satiety.

The purpose of this study was to evaluate the effects of carob seed flour as well as bran particle size on glycemic index, load, and response.

The Study

Researchers from the Agricultural University of Athens in Greece conducted this randomized trial, involving 10 healthy volunteers. They were instructed to attend eight weekly visits, fasting for 10 to 14 hours.

There were four different bread formulations prepared for this trial:  

  • White bread
  • Bread enhanced with coarse wheat bran
  • Bread enhanced with fine wheat bran
  • Bread enhanced with fine wheat bran and 10% carob-seed flour

In random order, each participant consumed the following throughout the eight weeks of the trial: glucose (three visits), white bread (two visits), coarse wheat bran bread (one visit), fine wheat bran bread (one visit), and fine wheat bran bread with carob (one visit).

Measured outcomes included the glycemic index, glycemic load, and glycemic response to each of the four types of breads

The Results

Researchers observed that bread enhanced with coarse wheat bran produced lower glycemic index and lower glucose excursions (sudden spikes in blood sugar levels) than bread with fine wheat bran.

Additionally, bread with fine wheat bran and carob produced lower glycemic load and lower glucose excursions.

What Does this Mean?

The results of this study indicate that substituting white flour with carob helps improve glycemic control, even if it is used in small quantities. Enhancing breads with large-particle bran has shown to evoke such favorable effects. 

Authors of this trial believe that adding carob flour to breads helps control blood sugar thanks to its high soluble fiber content. However, they emphasize the need for other studies to understand these benefits in more depth, particularly the role of soluble fiber on glycemic index.

Other herbs that are beneficial for glycemic control include arracacha, oats, taro, and legumes like lentils, and beans.


  • Journal of Functional Foods, Effects of bran size and carob seed flour of optimized bread formulas on glycemic responses in humans: A randomized clinical trial, 2018


  1. Food and Bioprocess Technology. (2015). Jet Milling Effect on Functionality of Whole Wheat Flour and Bread. Retrieved August 25, 2021 from
  2. Nutrición Hospitalaria. (2015). Glycemic response to Carob (Ceratonia siliqua L) in healthy subjects and with the in vitro hydrolysis index. Retrieved August 25, 2021 from