Breakfast glycaemic response in patients with type 2 diabetes: effects of bedtime dietary carbohydrates

Eur J Clin Nutr. 1999 Sep;53(9):706-10. doi: 10.1038/sj.ejcn.1600837.


Objectives: Bedtime carbohydrate (CHO) intake in patients with type-2 diabetes may improve glucose tolerance at breakfast the next morning. We examined the 'overnight second-meal effect' of bedtime supplements containing 'rapid' or 'slow' CHOs.

Design: Randomized cross-over study with three test-periods, each consisting of two days on a standardized diet, followed by a breakfast tolerance test on the third morning.

Setting: The Lundberg Laboratory for Diabetes Research, Sahlgrenska University Hospital, Göteborg, Sweden.

Subjects: Sixteen patients with type 2 diabetes on oral agents and/or diet.

Interventions: Two different bedtime (22.00 h) CHO supplements (0.46 g available CHO/kg body weight) were compared to a starch-free placebo ('normal' food regimen). The CHOs were provided as uncooked cornstarch (slow-release CHOs) or white bread (rapid CHOs).

Results: On the mornings after different bedtime meals we found similar fasting glucose, insulin, free fatty acid and lactate levels. However, the glycaemic response after breakfast was 21% less after uncooked cornstarch compared to placebo ingestion at bedtime (406 +/- 46 vs 511 +/- 61 mmol min l(-1), P < 0.01). In contrast, it did not differ when the evening meal consisted of white bread (451 +/- 57 mmol min l(-1)) compared to placebo. According to an in vitro analysis, uncooked cornstarch contained approximately 4 times more slowly digestible starch as compared to white bread.

Conclusions: A bedtime meal providing uncooked cornstarch improved breakfast tolerance the next morning while, in contrast, this was not found following a bedtime meal of white bread. The results are consistent, therefore, with the concept that an increased intake of slowly digestible carbohydrates exert an overnight second-meal effect in patients with type 2 diabetes.

Publication types

  • Clinical Trial
  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Blood Glucose / metabolism*
  • Cross-Over Studies
  • Diabetes Mellitus, Type 2 / blood*
  • Dietary Carbohydrates / administration & dosage*
  • Dietary Carbohydrates / metabolism*
  • Digestion
  • Fatty Acids, Nonesterified / blood
  • Female
  • Humans
  • Insulin / blood
  • Lactates / blood
  • Male
  • Middle Aged
  • Starch / administration & dosage
  • Starch / metabolism
  • Time Factors


  • Blood Glucose
  • Dietary Carbohydrates
  • Fatty Acids, Nonesterified
  • Insulin
  • Lactates
  • Starch