Effects of a large breakfast versus large dinner on blood glucose homeostasis during a day of inactivity
E.B. Parr Appl. Physiol. Nutr. Metab. Vol. 41, 2016 S379
Patterns of energy intake play a major role on glucose metabolism.
Postprandial glucose concentrations may be manipulated by reducing
energy consumption at dinner and increasing energy intake at breakfast.
The benefit of a smaller evening meal may largest for individuals
with disrupted glucose metabolism, a cohort who are largely inactive
on a daily basis.
We aim to test the hypothesis that increasing the
amount of energy consumed at breakfast would improve blood glucose
metabolism during periods of prolonged sitting in overweight/
obese men and women with prediabetes. To date, eight adults with
prediabetes (impaired fasting glucose: >6.0 mmol/L and/or impaired
glucose tolerance: >7.8-11.0 mmol/L, age: 57 ± 5 y, body mass: 90.5 ±
13.6 kg, mean ± SD) have completed two 10 h laboratory visits consisting
of sitting uninterrupted for breakfast (0900), lunch (1300) and
dinner (1700) meals of either 20%, 30% and 50% energy intake (Dinner
condition) or 50%, 30%, and 20% energy intake (Breakfast condition),
respectively, with the same meal composition (50% carbohydrate, 20%
protein, 30% fat). Continuous glucose monitors (CGM) measured interstitial
[glucose] from 0800 on the day of a trial to 0800 the morning
after. The total 24 h area under the curve (AUC) [glucose] was not
different between conditions (P=0.21). The incremental AUC (iAUC)
between breakfast and lunch tended to be higher in the Breakfast
condition (P=0.055). Due to a drop in blood [glucose] prior to lunch in
the Dinner condition, the iAUC from lunch to dinner was greater for
Dinner vs Breakfast conditions (P=0.002), but no difference in iAUC
between conditions from dinner to 0800 the following day (P=0.27)
was observed.
Our preliminary findings indicate that while the total
24 h AUC does not support a difference in blood glucose regulation
when having a large morning meal compared to a large evening meal,
a more consistent (i.e. diminished excursions) blood glucose concentration
profile was observed across a day in the Breakfast condition.
These findings suggest that a larger morning meal balanced by a
smaller evening meal could benefit pre-diabetic individuals in the
long term regulation of blood glucose concentrations.