We report the effect of mild exercise on serum magnesium level. 36 healthy female subjects were examined. A bicycle ergometer was used. Amount of exercise corresponding to 30 and 40% of the maximum oxygen uptake were imposed for 10, 20 and 30 minutes, respectively, 3 times a week for 6 weeks. Serum magnesium levels decreased slightly but not significantly. There was no significant difference between serum magnesium levels of the inactive groups and more active groups. We speculated that mild exercise affects serum magnesium.
Molokhia (Corchorus olitorius) leaves used in Egypt for popular diets are rich in contents of minerals.@Evaluations of magnesium (Mg) and calcium (Ca) in molokhia powder (MP) for nutrient were examined.@Twenty four male Wister rats, 3 weeks old, were divided into 3 groups, and given 3 kinds of the synthetic diets; 1) 0% MP (control), 2) 10% MP, 3) 20% MP (minerals and vitamins concentrations of the diets were finally same, especially Mg concentration was high in 20% MP group) for 9 weeks.@Mg and Ca concentrations in plasma and tissues were determined by ICP-AES. The body weight gain in 20% MP group rats was significantly lower than these in other groups.@Mg concentration in tibia of the 20% MP group rats was high compared with that of the control group rats.@Mg concentration in plasma of the 20% MP group rats was higher than those of other groups rats.@Ca concentration of plasma of the 20% MP group rats was lower than that of the control group rats.@The body weight gain, and Mg and Ca concentrations in plasma and tissues of the rats fed the diet containing 10% MP were not significantly changed compared with these in rats fed the normal diet (0% MP).@These results suggest that Mg and Ca in molokhia leaves could be utilized as same as MgCO3 and CaHPO4 or CaCO3 in rats.
Three groups were compared about serum, erythrocyte or urine magnesium (Mg) and zinc (Zn) levels in this investigation, consisting of outpatients with essential hypertension, outpatients with diabetes mellitus and control healthy subjects (the controls). In total patients of both sexes serum Mg was lowest in diabetic outpatients (diabetics) and then lower in hypertensive outpatients (hypertensives) among these 3 groups. Even in either male or female patients, serum Mg lower in diabetics as compared to the controls. Serum Zn was lower in total hypertensives or diabetics as compared to the controls. Erythrocyte Mg in total patients and females was lower in diabetics compared to hypertensives, when erythrocyte Zn in total patients was lower in diabetics as compared to the controls. Erythrocyte Zn in total patients was lower in either diabetics or hypertensives as compared to the controls. In females erythrocyte Mg and Zn were lower in diabetics than in the controls. In addition, serum ionized Mg (Mg++) was lower in either totals or females with diabetes mellitus as compared to the controls or hypertensives. There were significantly positive correlation serum Mg and Zn in females (r=0.405), between serum Mg and erythrocyte Mg in both males and females (r=0.373 and 0.534, respectively) and between serum Zn and erythrocyte Zn in females (r=0.396). On the other hand Mg levels of 24-hour urine were lower in hypertensives as compared to the other groups. Diabetics showed both higher and lower levels of 24-hour urine, resulting in the almost same level of urine Mg on an average to that of the controls. Zn levels of 24-hour urine did not differ among 3 groups, indicating no increment of urine in diabetics.
In order to clarify the relationships among urine magnesium (Mg), potassium (K), catecholamines and aldosterone, 105 subjects aged 63.7+-10.7 years (M+-SD) were recruited in this study, consisting of 41 male patients with essential hypertension, 45 female patients with essential hypertension, 8 male healthy subjects and 11 female healthy subjects. Thereafter, the additional subjects were enrolled to confirm the relations between urine Mg and catecholamines, resulting in 178 subjects aged 62.1+-11.7 years who consisted of 69 male hypertensives, 64 female hypertensives, 21 male healthies and 24 female healthies. The collection of 24-hours urine was carried out in these subjects to measure Mg, K, catecholamine and aldosterone. There was found a significantly positive correlation between urine Mg and K concentrations. A positive correlation between urine Mg and aldosterone concentrations was also significant in hypertensives of both sexes, indicating an intimate relation of K to aldosterone compared to Mg. Furthermore, significantly positive correlations were found between urine K and norepinephrine, epinephrine or dopamine concentrations in male hypertensives. By increasing numbers of subjects the correlations between urine Mg and norepinephrine concentrations in both male hypertensives and male healthies became significant. On the other hand there were revealed significant correlations among norepinephrine, epinephrine and dopamine in hypertensives of both sexes, and also a positive correlation between urine dopamine and aldosterone concentrations, showing an intimate relation of dopamine to aldosterone. It is concluded from these findings that urine Mg and K relate to urine catecholamines and aldosterone.
To improve magnesium absorption through the reduction of phytic acid content, defatted soybean was fermented by aspergillus usami. After fermentation, phytate content was only trace and the phytase activity was detected in the fermented soybean. Apparent magnesium absorption was significantly higher in rats fed the fermented soybean diet than animals fed the intact soybean diet. In addition, even if sodium phytate was added to the fermented soybean diet, apparent magnesium absorption was as much as in rats fed the fermented soybean diet. Magnesium solubility in the lower small intestine was higher in rats fed the fermented soybean diet with or without adding phytate than that in rats fed the soybean diet. Magnesium concentrations in the femur of both of the fermented soybean groups were higher than that of the soybean group. These results suggested that fermentation of defatted soybean increased magnesium bioavailability. It is also possible that the fermented soybean can be used as phytase source.
Cytosolic free calcium ([Ca2+]i) and magnesium ([Mg2+]i) concentrations were estimated in the smooth muscle cells of thoracic aorta isolated from Mg-deficient and control rats using fura-2/AM and mag-fura-2/AM, respectively. Adult male Wister rats were fed with a Mg-deficient diet (0.001% Mg) for 30 days with control groups (0.07% Mg). The thoracic aortic strips without endothelium were loaded with fura-2/AM or mag-fura-2/AM in the presence of 0.5 or 1.0mM Mg2+, then [Ca2+]i or [Mg2+]i was measured in the same Mg2+ condition. [Ca2+]I of the thoracic aorta isolated from Mg-deficient rats (254.9±13.1nM) in the presence of 1.0mM Mg2+, however [Mg2+]I was not significantly different between two groups in both Mg2+ levels. These results suggest that [Ca2+]i, but not [Mg2+]i, of@thoracic aorta might be increased by hypomagnesemia during dietary Mg-deficiency.
We performed a nutritional survey in 801 middle-aged men and investigated total magnesium intake, magnesium density (mg/1000kcal), magnesium intake by food groups and the contribution ratio of food groups to total magnesium intake. The mean daily intake of magnesium was 237mg. Subjects with higher intake of magnesium or magnesium density took more magnesium from pulses, fishes and shellfishes to total magnesium intake were higher and that of cereals was lower in subjects with higher intake of magnesium. Subjects with higher intake of magnesium per energy intake showed higher intake of calcium, phosphorus, iron, potassium and copper and lower intake of total energy and lipid than those with lower intake.
The balance of magnesium (Mg), calcium (Ca), phosphorus (P) were studied in 10 healthy males (aged from 19 to 26 yrs) under a relatively low Mg diet with or without Mg supplement. Experimental period was 15-days composed of a balance period of 8 days (two consecutive 4-days periods), with a 4-days pre-balance and 3-days post-balance period. Throughout the experiment subjects ingested the diets contained 150mg/d of Mg as composition of common foods, five of them were additionally supplemented with 300mg/d Mg oxide (180mg/d as Mg). Daily Mg balances at dietary Mg intake of 150mg/d and 330mg/d were 4+-10mg/d and 11+-10mg/d respectively. Daily balance of Ca and P were not affected by dietary Mg levels. This study indicated that Mg balanced at wide range of dietary Mg levels.
This page was first uploaded to The Magnesium Web Site on February 17, 1996