The following research papers have been selected and summarised by our Scientific Affairs Analyst at Nestlé, Jean Kim (PhD). They are designed to provide a topline overview and summary of the relevant research paper – they are not a scientific review. For further information and full details of the research paper, please read the relevant abstract by clicking on the links provided.

1. Effect of oat processing on glycaemic response

2. Breakfast consumption and childhood and adolescent Obesity

3. Personality and time-of-day preference as predictors of breakfast behaviours



1. Effect of oat processing on glycaemic response


A systematic literature review of the different processing methods of whole-grain oat cereals on glycaemic response.


Tosh SM and Chu YF (2015). Systematic review of the effect of processing of whole-grain oat cereals on glycaemic response. British Journal of Nutrition, 114, 1256-62.



There is evidence that whole grain oats have the ability to lower post-prandial blood glucose.1 However, the processing of oats may change their physical characteristics, leading to different glycaemic responses. The objective of the current review was to compare the GI of different whole grain oat food products to determine whether milling and cooking practices influenced glycaemic response.

Differences between products were discussed in terms of composition, processing history and product characteristics that influenced starch digestibility.


Summary of findings

The review identified 20 publications containing 56 individual tests. An additional 17 unpublished tests were found in an online database. Of the 72 measurements included in the review, two were for steel-cut oats, 11 for large flake oats, seven for quick cooking (small flake) oats, nine for instant oatmeal and 28 for muesli or granola. The effect of different processes on acute post-prandial glycaemic response was quantified using the Glycaemic Index (GI) for product comparisons, as GI was shown to be the most commonly used indicator of glycaemic response for whole oat foods.

A broad distribution of glycaemic responses was observed for different whole grain oat products. Steel-cut oats (GI=55), large flake oats (GI=53) and muesli and granola (GI=56) elicited low to medium glycaemic response, while quick cooking oats (GI=71) and instant oatmeal (GI=75) produced significantly higher glycaemic response. As the products only differed in the way they were milled and cooked, the range of glycaemic responses were most likely due to differences in processing, not composition. Smaller particle size and increased starch gelatinisation appeared to also increase the glycaemic response.



Many authors did not specify the cooking method, as a result there were insufficient data points in all of the categories to perform statistical analysis of whether the cooking method affected the GI.


The Bottom Line

Milling and cooking practices appear to produce significant changes in the digestibility of starch in wholegrain oatmeal products. Steel-cut and large flake hot oatmeal porridges, muesli and granola consistently demonstrated medium to low glycaemic responses, making them good options for people concerned about blood glucose response to foods.

“Differences in processing protocols and cooking practices modify the glycaemic response to foods made with whole grain oats”



  • Tosh SM (2013), Review of human studies investigating the post-prandial blood-glucose lowering ability of oat and barley food products. Eur J Clin Nutr 67, 310-17