Unidentified 'meat factor' enhances iron absorption

Dust off the barbie - a rare steak is the most concentrated form of iron available, according to a study commissioned by Meat New Zealand.

Dr Roger Purchas, of the Institute of Food, Nutrition and Human Health, said that advertising campaigns had made it known red meat was a more readily available source of iron than chicken or spinach on a weight basis.

But until recently little was known about how iron levels were affected by how meat was cooked or cut.

The study by Massey University and AgResearch found the amount of iron varied between cuts, and that long, slow cooking also reduced the iron available.

As expected, iron levels tended to be higher in beef than in lamb, and in darker red cuts rather than paler ones.

An as yet unidentified "meat factor" enhanced the body's ability to absorb not only the iron in meat, but other iron in the same meal.

Cooking meat at low temperatures for longer appeared to decrease the amount of available iron, because it turned soluble "haem" iron into the less desirable non-haem form through the loss of cooking juices.

Dr Purchas said iron was also found to be lost in juices released from meat that had been frozen over eight days and thawed.

- NZPA