Effect of nicotinamide treatment on the residual insulin secretion in type 1 (insulin-dependent) diabetic patients

Diabetologia. 1989 May;32(5):316-21. doi: 10.1007/BF00265549.


In vivo and in vitro experiments have shown that nicotinamide enhances the regeneration of rat B cells. Nicotinamide has been administered to human subjects at a dose of 3 g/day for more than one year without any serious side effects. A trial was conducted to study if nicotinamide could protect B cells in Type I (insulin-dependent) diabetic patients with established diabetes, but still with residual insulin secretion, the latter being evaluated throughout the study period. A randomized double-blind study was carried out on 26 Type I diabetic patients aged 15 to 40 years who had been treated with insulin for 1 to 5 years but who had a residual insulin secretion characterized by a glucagon stimulated C-peptide level higher than 0.1 nmol/l. They were given either 3 g/day of nicotinamide or a placebo for nine months. At baseline the treated and control groups did not differ according to age, diabetes duration, insulin dose, HbA1c or C-peptide levels. Three patients dropped out of the study. At 9 months there were no significant changes in the insulin doses required. However, HbA1c rose in the control group (8.1 +/- 0.4 vs 9.8 +/- 0.5%, p less than 0.05) but not in the nicotinamide treated group (7.5 +/- 0.5 vs 6.9 +/- 0.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • C-Peptide / blood
  • Diabetes Mellitus, Type 1 / blood*
  • Diabetes Mellitus, Type 1 / drug therapy
  • Female
  • Glucagon
  • Glycated Hemoglobin A / analysis
  • HLA-DR Antigens / analysis
  • Humans
  • Insulin / metabolism*
  • Insulin / therapeutic use
  • Insulin Secretion
  • Islets of Langerhans / drug effects
  • Islets of Langerhans / metabolism*
  • Male
  • Niacinamide / pharmacology*


  • C-Peptide
  • Glycated Hemoglobin A
  • HLA-DR Antigens
  • Insulin
  • Niacinamide
  • Glucagon