High prevalence of lactose absorbers in Northern Sardinian patients with type 1 and type 2 diabetes mellitus

Am J Clin Nutr. 2001 Mar;73(3):582-5. doi: 10.1093/ajcn/73.3.582.

Abstract

Background: Increased intestinal lactase activity has been shown to occur in alloxan and streptozotocin diabetic rats.

Objective: The objective of this study was to determine whether increased intestinal lactase activity is present in humans with diabetes mellitus.

Design: We assessed the capacity to digest lactose by measuring breath-hydrogen production after oral administration of lactose in 50 patients with type 1 diabetes, 50 patients with type 2 diabetes, and 50 healthy control subjects from Sassari, Sardinia, Italy, a population characterized by a low prevalence of lactase persistence (lactose absorbers).

Results: Fourteen percent of control subjects were lactose absorbers, compared with 48% of patients with type 1 diabetes and 52% of patients with type 2 diabetes (P < 0.005). The odds ratio of lactase persistence in patients with type 1 diabetes was 5.3 (95% CI: 2.0, 14.0) and in patients with type 2 diabetes was 5.5 (95% CI: 2.1, 14.5).

Conclusions: Diabetes is associated with increased intestinal lactase activity in humans. Consequently, there is a greater exposure to glucose and galactose in diabetic patients with high lactose consumption. This may explain the association between diabetes and the risk of cataract.

MeSH terms

  • Adult
  • Breath Tests
  • Case-Control Studies
  • Cataract / etiology
  • Diabetes Mellitus, Type 1 / complications*
  • Diabetes Mellitus, Type 1 / metabolism
  • Diabetes Mellitus, Type 1 / physiopathology
  • Diabetes Mellitus, Type 2 / complications*
  • Diabetes Mellitus, Type 2 / metabolism
  • Diabetes Mellitus, Type 2 / physiopathology
  • Female
  • Humans
  • Intestinal Absorption
  • Italy / epidemiology
  • Lactase
  • Lactose / metabolism*
  • Lactose Intolerance / epidemiology*
  • Male
  • Middle Aged
  • Odds Ratio
  • Prevalence
  • Risk Factors
  • beta-Galactosidase / metabolism*

Substances

  • Lactase
  • beta-Galactosidase
  • Lactose