High levels of magnesium in the blood reduce the risk of fractures by 44 percent, according to a new study published in the European Journal of Epidemiology. The study followed 2,245 men aged between 42 and 61 over a 20-year period.
The findings showed that the men who had lower levels of magnesium in the blood had an increased risk of fractures, particularly fractures of the hip.
In contrast, none of the 22 men who had very high magnesium levels (> 2.3 mg/dl) experienced a fracture during the follow-up period.
The study states that for elderly people, eating more magnesium-rich food (walnuts, bananas, dark chocolate, wholegrain cereals, green vegetables, mineral water, etc.) may not necessarily increase magnesium levels in the blood.
Absorption of magnesium decreases with age, and older people are more likely to take medication or to have bowel disorders which interfere with its absorption. In these cases, magnesium supplementation may be useful.
One of the best tolerated forms of magnesium is magnesium bisglycinate which is the magnesium salt of glycine, an amino acid in chelated form. The bioavailability of this chelated form seems to be very good, according to studies undertaken in the US, and this type of magnesium does not seem to have any particular disadvantages.
Magnesium citrate also has a greater absorption rate than magnesium oxide and the chelated forms of magnesium. Citric acid helps with the absorption of magnesium by increasing its solubility. This is therefore considered to be a good choice suitable for everyone.
Lastly, magnesium glycerophosphate is a fat-soluble salt which several studies indicate is the least laxative form of magnesium.
Recommended magnesium intake is around 70 mg per day for children aged up to 3 years old, around 250 mg for the 9-13-year-old age range, and 350 mg for adult women and 420 mg for adult men.