GlyCoBrain Observational Study

Condition(s) studied

Study summary

Breakfasts with a high glycaemic index (GI) resulting in sharp rises in blood glucose may adversely affect memory and attention, particularly in the late postprandial phase (i.e., 120-180 minutes after breakfast). Young adults may be particularly responsive to these adverse effects on cognition since they are prone to experience circadian misalignment because their midpoint of sleep (i.e., chronotype) is biologically most delayed in young adulthood. Our recent research suggests that persons with a later chronotype exhibit no diurnal difference in response to a high GI meal consumed in the morning and evening, suggesting that consumption of an early breakfast "against the inner clock" may be adverse for their glycaemic response and that consumption of an early breakfast may present a burden for those with a later chronotype. Indeed, persons with later chronotypes commonly tend to exhibit less favourable eating pattern. Hence, consuming an early breakfast, e.g. in preparation for an exam, may be more problematic for persons with later chronotypes and it may be more likely that these persons choose less favorable foods for breakfast.

Thus, it remains to be clarified whether persons with a later chronotype:

1. usually consume breakfasts with a higher dietary GI than those with an earlier chronotype. Addressing this hypothesis needs to consider both the first and second breakfast (i.e., all meals until noon), since breakfast skipping may be common particularly among persons with a later chronotype
2. are more prone to consume foods from higher GI sources in preparation for an exam in the morning than those with an earlier chronotype.
3. consume breakfasts of a higher energy density and a lower micronutrient adequacy than persons with an earlier chronotype.

In this study (GlyCoBrain (Glycaemic index Cognition Brain) observational study), 350 students from the University of Paderborn, aged between 18 and 25, will be recruited until the end of February 2025. A questionnaire-based screening will assess breakfast habits and chronotype using the Munich ChronoType Questionnaire (MCTQ). In addition, students will be asked to fill in two 24-h recalls (myFood24) to provide information on their habitual diet (including breakfast). The screening will be followed by two controlled intervention studies examining the effect of (i) a high GI breakfast (GlyCoBrain intervention study 1) and (ii) a breakfast causing an (isolated) reactive hypoglycaemia (GlyCoBrain intervention study 2) on the course of memory and attention in the postprandial phase.

Eligibility

Primary outcome measure(s)

• Breakfast quality, dietary GI and nutrient composition — At inclusion into the study and after 6 days
  2 times Computer-assisted 24-hour recall of consumed foods and beverages in the past 24 h
• Breakfast food choice in preparation of an exam — Assessed once at the beginning of the study
  Questionnaire inquiring selected food items, beverages and meal replacements

Trial sites (1)

Other trials for the same condition