Our intervention study starts on 4 April 2025!

Conditions of participation:

You will be invited by e-mail if you

• have taken part in the screening;
• you are an early or late chronotype;
• you are studying at Paderborn University.

Unfortunately, you cannot participate if you

• Have not taken part in the screening
• You are an intermediate chronotype
• You regularly smoke and/or consume cannabis
• Leave all other points as they are

We would like to invite you to take part in a 180-minute intervention study to investigate how the glucose response to different sugar solutions with different glycaemic indices or different potential to trigger reactive hypoglycaemia affects memory performance.

In the intervention studies described here, we would now like to find out

• what effects a high GI breakfast has on memory performance in young healthy students (study 1)
• the effects of (isolated) reactive hypoglycaemia on memory performance in young healthy students (Study 2).

Effects of the glycaemic index of breakfast and reactive hypoglycaemia on the course of memory performance and attention in young adults - relevance of chronotype.

If you participated in the screening and we were able to determine that you are a typical lark or owl, we will contact you again and invite you to our intervention studies 1 and 2 (controlled nutrition and cognition study). Here we briefly describe what we would then ask you to do.

In these two studies, we would like to find out what effects drinks with a high glycaemic index and/or (isolated) reactive ^{hypoglycaemia1} have on memory and attention performance in larks and owls.

^1Reactivehypoglycaemia, also known as postprandial hypoglycaemia, is a drop in blood glucose (blood sugar) levels to below fasting levels. This typically occurs within 1-3 hours after eating and is not related to diabetes.

Die Interventionsstudien 1 und 2 besitzen den gleichen Ablauf, sie unterscheiden sich lediglich in der Art des Getränks, das getestet werden soll. Die Interventionsstudie startet im April 2025.

Die Interventionsstudien umfassen jeweils 3 Untersuchungstage für jede*n Teilnehmer*in.

Wo­che 1

• Vorbereitungstag (Tag 1) i.d.R. Freitag
• Interventionstag (Tag 2) i.d.R. Montag-Donnerstag

Wo­che 2

• Interventionstag (Tag 3) i.d.R. Montag-Donnerstag

Wenn die o.g. Wochentage Feiertage sind, verschiebt sich der jeweilige Tag um einen Tag nach vorn.

In the course of the studies, we ask you to carry out the following measurements or have them carried out:

• Anthropometric measurements including body composition (on preparation days),
• Fasting blood sampling from the vein (on preparation days),
• Continuous glucose measurement using a sensor that you wear on your stomach or upper arm (sensor will be placed on preparation days ),
• Determination of your activity and night-time rest phases on preparation days and intervention days using a sensor that you wear on your wrist
• Drinking a test drink (on intervention days)
• Repeated measurements of attention and memory performance over the course of 180 minutes (on intervention days)
• manual blood glucose measurement from the earlobe (on intervention days)
• repeated saliva samples (on intervention days)
• heart rate determination using a pulse belt (on intervention days)

If you take part in the controlled nutrition study,

• you will receive an expense allowance of up to €200 (€100 per intervention study),
• you will receive a dinner from us on the preparation days and a test meal (drink) on the intervention days,
• you will receive an evaluation of your activity and rest phases as an example for one day,
• you will receive feedback on your glucose profile on 2 study days,
• you will again find out the composition of your body (water, fat, muscle mass percentage), which we determine using bioelectrical impedance analysis.