Effect of dietary magnesium on glucose tolerance and plasma lipid during oral contraceptive administration in female rats

Abstract

Studies that associated oestrogen-progestogen oral contraceptive (OC) use with altered glucose and lipid metabolisms in women did not account for possible influence in dietary magnesium. The use of OC and glucose and lipid metabolism seems to remain a broad public health concern since over 100 million women use OC worldwide for a prolonged period of time. The study, therefore, sought to investigate in a female rat model whether or not glucose intolerance and dyslipidaemia associated with OC are influenced by dietary magnesium status. Control and OC-treated rats were maintained on control diet, whereas OC+ Mg- treated rats were on high magnesium diet. OCtreated and OC+Mg treated rats also received a combination of OC steroids, ethinyl oestradiol and norgestrel (orally). When compared with the controls, OC treatment led to significant reduced glucose tolerance and plasma HDL-cholesterol and significant increases in plasma LDL-cholesterol and atherogenic indices in OC- treated rats. Treatment with OC did not result in significant attenuation in these parameters in OC+Mg- treated rats when compared with the controls. In conclusion, these results suggest that impaired glucose tolerance and dyslipidaemia associated with OC use may be prevented by increased dietary magnesium.