Magnesium-deficient high-fat diet: effects on adiposity, lipid profile and insulin sensitivity in growing rats

Clin Nutr. 2014 Oct;33(5):879-88. doi: 10.1016/j.clnu.2013.10.004. Epub 2013 Oct 16.


Background & aims: To determine if magnesium deficiency aggravates the effects of a high-fat diet in growing rats in terms of obesity, lipid profile and insulin resistance.

Methods: The study population comprised 48 newly weaned male Wistar Hannover rats distributed into four groups according to diet, namely, control group (CT; n = 8), control diet provided ad libitum; pair-feeding control group (PF; n = 16), control diet but in the same controlled amount as animals that received high-fat diets; high-fat diet group (HF; n = 12), and magnesium-deficient high-fat diet group (HFMg(-); n = 12). The parameters investigated were adiposity index, lipid profile, magnesium status, insulin sensitivity and the phosphorylation of proteins involved in the insulin-signaling pathway, i.e. insulin receptor β-subunit, insulin receptor substrate 1 and protein kinase B.

Results: The HF and HFMg(-) groups were similar regarding gain in body mass, adiposity index and lipid profile, but were significantly different from the PF group. The HFMg(-) group exhibited alterations in magnesium homeostasis as revealed by the reduction in urinary and bone concentrations of the mineral. No inter-group differences were observed regarding glucose homeostasis. Protein phosphorylation in the insulin-signaling pathway was significantly reduced in the high-fat groups compared with the control groups, demonstrating that the intake of fat-rich diets increased insulin resistance, a syndrome that was aggravated by magnesium deficiency.

Conclusions: Under the experimental conditions tested, the intake of a magnesium-deficient high-fat diet led to alterations in the insulin-signaling pathway and, consequently, increased insulin resistance.

Keywords: Glucose; Insulin; Lipid enriched diet; Magnesium; Obesity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adiposity*
  • Animals
  • Body Composition
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Diet, High-Fat / adverse effects*
  • Fasting
  • Insulin / blood
  • Insulin Receptor Substrate Proteins / genetics
  • Insulin Receptor Substrate Proteins / metabolism
  • Insulin Resistance*
  • Lipids / blood*
  • Magnesium / administration & dosage
  • Magnesium Deficiency / blood*
  • Male
  • Nutritional Status
  • Obesity / blood
  • Phosphorylation
  • Proto-Oncogene Proteins c-akt / genetics
  • Proto-Oncogene Proteins c-akt / metabolism
  • Rats
  • Rats, Wistar
  • Signal Transduction
  • Triglycerides / blood
  • Weaning


  • Cholesterol, HDL
  • Cholesterol, LDL
  • Insulin
  • Insulin Receptor Substrate Proteins
  • Irs1 protein, rat
  • Lipids
  • Triglycerides
  • Proto-Oncogene Proteins c-akt
  • Magnesium