Meal effect on magnesium bioavailability from mineral water in healthy women.
BACKGROUND
Magnesium intakes in many industrialized countries are below recommended daily allowances. Magnesium-rich mineral water may contribute to coverage of magnesium requirements by providing significant amounts of natural, energy-free, bioavailable magnesium.


OBJECTIVE
The objectives were to determine magnesium bioavailability from magnesium-rich (110 mg/L) mineral water in healthy subjects when consumed alone and to evaluate the effect of simultaneous meal consumption.


METHODS
Magnesium bioavailability was measured in 10 healthy women with the use of a crossover design. Stable magnesium isotopes ((25)Mg and (26)Mg) were administered orally with mineral water, which was consumed with or without a meal. Apparent magnesium absorption was determined by fecal monitoring, and magnesium retention was determined from urinary excretion of magnesium isotopes.


RESULTS
The mean (+/-SD) magnesium absorption from mineral water consumed alone was 45.7 +/- 4.6% (range: 40.2-55.5%) and was significantly greater (P = 0.0001) when it was consumed with a meal (52.3 +/- 3.9%; 46.2-60.2%), a relative difference of 14.4%. Magnesium retention also was significantly greater (P = 0.0004) when mineral water was consumed with a meal (41.5 +/- 4.2%; 35.2-50.6%) than when consumed alone (37.4 +/- 4.0%; 33.1-47.0%), a relative difference of 11.0%.


CONCLUSIONS
In healthy young women, approximately 50% of the magnesium from magnesium-rich mineral water was absorbed when consumed alone. Magnesium bioavailability from mineral water is enhanced when the water is consumed with a meal, perhaps because of a slower gastrointestinal transit time, the presence of digestion products from the meal, or both. Regular consumption of magnesium-rich mineral water could make a valuable contribution to magnesium requirements.
Sabatier
Magalie
M
Perrier Vittel Water Institute, Vittel, France.
Arnaud
Maurice J
MJ
Kastenmayer
Peter
P
Rytz
Andreas
A
Barclay
Denis V
DV
D000328:Adult; D001682:Biological Availability; D018592:Cross-Over Studies; D005260:Female; D005502:Food; D006801:Humans; D008274:Magnesium / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D008875:Middle Aged; D008900:Mineral Waters
D008900:Mineral Waters; D008274:Magnesium