The urge to get female athletes to eat red meat is based on the fact that beef contains ample quantities of haem iron, which is usually much more readily absorbed than the iron in plant products. Thus, a gram of iron in red meat actually represents a greater amount of available iron, compared to a gram of the mineral in leafy vegetables. For women with modest intakes of iron, red-meat iron might make a huge difference.

To determine the benefits of red-meat consumption, scientists at Ball State University recently compared two groups of female runners. Members of both groups were about the same age (38 years), weighed the same (128 pounds), possessed the same V02max (about 50 ml/kg/min), and ran the same number of miles per week (32). However, one group regularly consumed red meat (the RM runners), while the other group (the NO-RM runners) wolfed down poultry and fish but basically ate almost no red meat at all (less than 3 ounces per week).

Runners in both groups actually ate the same amount -14 mg of iron each day, but RM runners ate six times as much haem iron. In spite of the similarity in iron intakes, eight of the nine runners in the NO-RM group had serum ferritin levels below 12 ng/100 ml, which represents nearly complete depletion of iron stores, while only two of the nine runners in the RM group had iron levels which were that low. Serum ferritin averaged a miserly 7 ng/100 ml for the NO-RM runners but checked in at a low but normal level of 20 ng/100 ml for the RM harriers. Three of the NO-RM runners had stage-two iron deficiency (indicating that not enough iron was being 'packaged' with red blood cells), versus just one of the RM athletes.

In other words, slapping some red meat on to the plate seemed to help RM runners keep their ferritin levels normal and avoid the perils of iron deficiency. The RM runners fared better than the NO-RM runners, even though both groups were eating the same total amount of daily iron.

Does that mean that female athletes should eat more red meat? Well, not exactly. One problem was that both groups of runners were eating abnormally low quantities of total calories each day (each group tucked in only 1700-1800 daily calories, too low for people running around five miles each day). That created a bad situation, since iron consumption is related to caloric intake. There's usually only five to six mg of iron present per 1000 calories, so a grand total of 1700-1800 calories usually leaves athletes short of the iron RDA. True, both groups ended up with 14 mg of iron each day, just a little shy of the RDA, but this intake clearly wasn't enough for the NO-RM athletes, since their non-haem iron wasn't absorbed so well.

So, the answer for the NO-RM athletes could have been more red-meat on their plates if they were willing or a higher caloric consumption if they were willing or iron supplementation (about 325 mg of ferrous sulphate per day). Instead of gobbling up more red meat, the NO-RM individuals could also have employed the classic 'iron-gathering' strategies eating high-iron foods together with orange juice or vitamin C, cooking in iron pans, and avoiding products which hinder iron absorption (tea, wheat bran, antacids, calcium-phosphate supplements).

('Influence of Dietary Iron Source on Measures of Iron Status among Female Runners, '

Medicine and Science in Sports and Exercise, vol. 21(1), pp. 7-10, 1989)