Aim: To investigate the effects of a low carbohydrate diet (<100 grams/day) and a high carbohydrate diet (>250 grams/day) on daytime (6:00-0:00) and nighttime (0:00-6:00) glucose dynamics in adults with type 1 diabetes.

Methods: Fourteen participants using sensor-augmented insulin pumps were included in a randomized crossover study with two 12-week intervention arms separated by a 12-week washout. Individual meal plans meeting the carbohydrate criteria were made for each study participant.

Results: Participant baseline characteristics were (mean ± SD): age 44 ± 12 years, BMI 24.8 ± 2.0 kg/m2, HbA1c 7.5 ± 0.4%, daily carbohydrate intake 152 ± 43 grams/day. Daily carbohydrate intake during the two intervention periods was (mean ± standard deviation) 98 ± 11 grams and 246 ± 34 grams, respectively. Distribution of glucose values are reported in the Table.

Discussion: Daytime hypoglycemia and nighttime hyperglycemia were lower during the low than the high carbohydrate diet. Further, more time was spent in normoglycemia at night during the low carbohydrate diet. These findings may be the results of smaller daytime meal boluses and fewer carbohydrates in the evening meal.


S. Schmidt: Speaker's Bureau; Self; Novo Nordisk A/S. A. Ranjan: None. M.B. Christensen: None. K. Nørgaard: Advisory Panel; Self; Abbott, Medtronic, Novo Nordisk A/S. Speaker's Bureau; Self; Bayer US, Medtronic, Roche Diabetes Care, Rubin Medical, Sanofi, Zealand Pharma A/S. Stock/Shareholder; Self; Novo Nordisk A/S.


Danish Diabetes Academy

Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. More information is available at