The study, published in Clinical Nutrition, finds that long-term hyperglycemia (a condition that leads to excess levels of magnesium in the urine) in patients with type-2 diabetes increases the risk of chronic complications such as nephropathy and may exacerbate and aggravate other clinical conditions associated with diabetes.
The authors said that an adequate magnesium intake is essential for subjects with type-2 diabetes, noting that magnesium intake was inadequate in most (82 percent) of the diabetic subjects studied.
“The results presented here show that magnesium intake by the study population was inadequate and that a high percentage of individuals presented alterations in the status of this mineral,” said the authors, led by Cristiane Hermes Sales from the Department of Food and Experimental Nutrition at the University of São Paulo, Brazil.
Magnesium is an essential in the regulation of many cellular processes and functions as a cofactor in a wide range of metabolic reactions.
Variations in the distribution of magnesium within the body are associated with several disease states, especially diabetes – a disorder which represents a global public health concern.
Sales and colleagues explained that the function of insulin is dependent on magnesium, as it is responsible for the activation of insulin receptors and for stimulation of proteins and substrates involved in insulin signaling.
Previous research has suggested the magnesium intake of patients with diabetes to often be below recommended levels. The researchers noted that there is also evidence that the magnesium status of patients with diabetes tends to alter, and that low levels may influence the evolution of the disease by generating further complications.
“Although some epidemiological studies have suggested that adequate magnesium intake reduces the risk of development of type 2 diabetes, there are still contradictions with respect to the role of low magnesium intake as a predictor factor for this disease,” said Sales and co workers.
The new research assessed magnesium intake status in patients with type 2 diabetes, in order to identify the parameters that best predict alterations in fasting glucose and plasma magnesium.
Sales and colleagues reported that 77 percent of participants presented one or more magnesium status parameters below the cut-off points for deficiency.
The glycemic levels of patients with type-2 diabetes were found to be influenced by magnesium levels.
The authors reported that concentrations of plasma magnesium were inversely correlated with fasting and 2-h post meal glucose levels, adding that levels of urine magnesium were directly associated with fasting glucose.
Within subjects evaluated, 63 percent were found to have low concentrations of plasma magnesium – indicating alterations in the compartmentalization of this mineral, according to the authors.
The authors said that since magnesium is essential, owing to its involvement in the magnesium-ATP complex that takes part in all transfer reactions that use and supply energy, it is not surprising that deficiency of the mineral is implicated in the impairment of metabolic control.
They concluded that impaired kidney function may lead to high levels of magnesium in the urine, which together with low magnesium intake can induce a rise of glucose in the blood.
Source: Clinical Nutrition
Published online ahead of print, doi: 10.1016/j.clnu.2010.12.011
“Influence of magnesium status and magnesium intake on the blood glucose control in patients with type 2 diabetes”
Authors: C.H. Sales, L.F.C. Pedrosa, J.G. Lima, T.M.A.M. Lemos, C. Colli