The hope of improving blood sugar levels by simply switching from the usual bread to specially enriched oat bread has been dashed. An international research team involving Prof Dr Anette Buyken and her "Public Health Nutrition" group at Paderborn University has shown that simply changing the daily bread is not enough to improve blood sugar levels: Swapping your daily bread alone is not enough to sustainably improve blood sugar control in people at increased risk of type 2 diabetes. The results of the study have now been published in the "American Journal of Clinical Nutrition".

Beta-glucan: proven dietary fibre with a "health claim"

The effect of food on blood sugar levels is indicated by the so-called glycaemic index (GI). The GI describes how much the carbohydrates in a food cause blood sugar to rise. As part of the "CarbHealth" study, a special bread was developed in Norway that has a comparatively low GI - in other words, it raises blood sugar levels less than conventional bread.

The special thing about this bread is that it has also been enriched with beta-glucans. Prof. Buyken explains: "Beta-glucans occur naturally in oats and barley and have been shown to have favourable effects on blood sugar levels, cholesterol balance and body weight. Due to these effects, the European Food Safety Authority has authorised products containing beta-glucans to carry a so-called 'health claim', which refers to their scientifically proven health effects." The bread used in the study was specially developed by the "Nofima" research institute in Norway and is the first of its kind to contain the required amount of beta-glucans for such a "health claim".

Realistic nutritional study with surprising results

Around 200 adults from Germany (Paderborn and Leipzig), Norway and Sweden took part in the "CarbHealth" study. Over a period of 16 weeks, they replaced their usual bread with the specially developed oat bread with beta-glucans or a wholemeal bread that was also developed for the study. The aim was to examine the effects of this change in diet on long-term blood sugar levels and other health parameters such as cholesterol and insulin levels.

While previous controlled studies have shown positive effects of beta-glucan, these cannot easily be proven under everyday conditions. "Of course, small changes such as eating more fibre-rich bread make sense in principle. However, our study shows that a single food - even if it contains proven health-promoting ingredients such as beta-glucan - does not have a major effect on long-term blood sugar levels," summarises Prof Buyken. "The results emphasise the importance of a fully balanced diet. It's important to look at the whole package and life circumstances - for example, how easily people have access to healthy foods."

The study was conducted in collaboration with researchers from the University of Bergen (Norway, consortium leader), the Nofima Research Institute (Norway), Chalmers University of Technology in Gothenburg (Sweden) and Leipzig University. The joint project was funded by the European Union with a total of 1.6 million euros as part of the "A Healthy Diet for a Healthy Life" initiative of the European research network "Interrelation of the Intestinal Microbiome, Diet and Health". The funding for the German cooperation partners comes from the Federal Ministry of Education and Research (BMBF).

This text was translated automatically.