During the 2002 Winter Olympics in Salt Lake City, a cleaning lady finds blood transfusion materials used by the Austrian cross country ski team. In the aftermath of the incident, three cross country skiers are banned from the next two winter Olympics. Blood doping is also part of the reason Lance Armstrong was stripped of his seven Tour de France titles.
Illicitly boosting the number of red blood cells in order to enhance athletic performance has been termed blood doping. Typically, red blood cells are isolated from drawn blood and then stored. They are then reinjected a few days before a competitive event. When the stored red blood cells are reinfused, a temporary excess occurs. Injecting hormones that stimulate red blood cell formation is another method used for achieving the same results. Why would elevated RBC levels boost athletic performance?
The percentage of blood that is composed of red blood cells, called hematocrit, in a typical adult male hovers around 45 percent. Red blood cells are responsible for transporting oxygen throughout the body and for circulating carbon dioxide to the lungs where it can be exhaled. Thus, an excessive amount of them, as experienced with blood doping, should increase the oxygen carrying capacity of blood, which could translate into greater endurance and speed, reduce fatigue and give the athlete an edge.
Red blood cells are basically little bags of hemoglobin, a protein that gives them their color. Each hemoglobin molecule contains four iron atoms. It is these four iron atoms that combine with four molecules of oxygen. A single red blood cell contains 250 million hemoglobin molecules. As a result, one microscopic red blood cell can scoop up about one billion molecules of oxygen! As you might suspect, the mineral iron is an integral part of the oxygen-energy–athletic edge story.
About 65-70% of the body’s iron supply is in hemoglobin. When evaluating iron levels there are several substances in the blood that can be tested. The hemoglobin test is the most common because of its low cost, the speed of the procedure, and its better performance compared with hematocrit. However, hemoglobin only detects the late stages of iron deficiency. A mild iron deficiency may not affect the hemoglobin concentration.1
Anemia occurs when the body does not have enough healthy red blood cells. Although it can be attributed to a variety of factors, one thing is for certain, the blood’s ability to transport oxygen is reduced. More specifically, iron deficiency anemia occurs as a direct result of a lack of iron. “Iron deficiency is the most common micronutrient deficiency in both developing and developed countries, particularly among children and women of childbearing age.”2 When hemoglobin molecules are normal, but red blood cells contain fewer than the usual number, a nutritional anemia is suspected.
Your body doesn’t make iron. You must get it from your diet. Dietary sources of iron come in two forms: heme and non-heme. The only place you will find heme iron is in hemoglobin and as such can only be consumed in meat. It is efficiently absorbed, but comes combined with the negative side effects associated with meat consumption.
This leads us to wonder: where do cows and chickens get their iron? Naturally, their iron stores came from greens and grains. Humans can get meet their iron needs with plants too. However, because plant sources of iron come in the non-heme form, they are a bit touchier. They have to be dissolved and repackaged in order to be absorbed.
For example, lentils and beans are high in iron. But, they also contain iron inhibitors, called phytates. If simply cooked, legumes can retain up to 92 percent of these inhibitors. Reportedly, soaking legumes in very warm water overnight yields the best results in reducing phytates. After soaking, make sure legumes are rinsed before cooking. All of the minerals contained in legumes will be better absorbed.
Whole grains are also a good source of iron. However, they too contain iron inhibitors. In a Swedish study, it was found that soaking rolled oats before cooking them as a breakfast cereal significantly increased iron absorption. Soaking allows enzymes, and other helpful organisms, to break down and neutralize phytic acid. As little as seven hours of soaking in warm water will neutralize a large portion of phytic acid in grains. The simple practice of soaking cracked or rolled cereal grains overnight will vastly improve their nutritional benefits.
Green leafy vegetables are another excellent source of iron. One cup of cooked spinach has almost twice as much iron as the same caloric amount of sirloin steak! But remember it is not as absorbable. One study reported however, that adding 63 mg of vitamin C to a meal rich in non-heme iron yielded a 2.9-fold increase in iron absorption. Ascorbic acid “is the most efficient enhancer of nonheme iron absorption when its stability in the food vehicle is ensured.”3
Even more significant than ascorbic acid though is your own stomach acid. It is a secret ingredient for non-heme iron absorption. It has been observed that as stomach pH rises, becoming less acid, absorption of non-heme iron decreases. Studies have found deficient stomach acid in children and adults with chronic anemia. When supplementary hydrochloric acid is given to people with anemia and low stomach acid, their iron absorption improves and their anemia disappears.
As you can see, getting enough iron in your diet is very important and entirely possible while following a plant-based diet. Additionally, consuming foods high in iron will ensure a diet packed with other important vitamins and nutrients. These foods will provide you energy, boost your performance, and help you live a healthier life. And that’s better than blood doping in our book!
References:
[1] Zuguo Mei, Ibrahim Parvanta, Mary E. Cogswell, Elaine W. Gunter, Lawrence M. Grummer-Strawn. Erythrocyte protoporphyrin or hemoglobin: which is a better screening test for iron deficiency in children and women? http://www.ajcn.org/content/77/5/1229.full. [2] Ibid. [3] B. Teucher, M. Olivares, H. Cori, Enhancers of iron absorption: ascorbic acid and other organic acids. http://www.ncbi.nlm.nih.gov/pubmed/15743017