Magnesium status and dietary intake of mid-old people in a rural area of China.

To evaluate the status and dietary intake of magnesium in mid-old people in a rural area of China, a total of 324 mid-old people (111 males and 213 females) aged 55-70 were randomly selected. All the subjects were divided into four groups: a normal group (N), a hypertension group (H), an impaired fasting glucose group (IFG) and a diabetic group (D). Magnesium, sodium, potassium, calcium, iron, zinc, and copper concentrations in red blood cells (RBC) were measured by emission spectroscopy (ICP-OES), and dietary intakes were surveyed by 24-hr recall questionnaires. The data were analyzed between groups and also between genders. The average body weight and BMI were 59.4 kg and 22.1 in subjects with IFG, and 62.4 kg and 23.5 in the diabetics, which were higher than those of the normal group (p < 0.05 and p < 0.01). The average magnesium concentration in RBC was significantly lower in the hypertension group than in the normal group (2.0 mmol/L vs. 2.2 mmol/L, p < 0.05). Groups H, IFG and D took less magnesium than group N (315.9 mg/d, 331.6 mg/d and 323.3 mg/d vs. 371.54 mg/d, p < 0.05). Women took less magnesium than men (326.2 mg/d vs. 373.7 mg/d, p < 0.05). There were no significant differences in other mineral concentrations in RBC and dietary intakes. Results of this study show that magnesium concentration in RBC is lower in mid-old people suffering hypertension as compared to healthy subjects. Dietary intakes of magnesium are lower in mid-old people suffering hypertension, IFG and diabetes as compared to healthy subjects. This indicates that an increase in the magnesium supply would be beneficial to mid-old people.