Pooped after Pilates? Yawning during Yoga? If you find yourself dreading exercise because you just don’t have the physical or mental energy to run up that first hill, your body could be telling you it’s deficient in iron. Unfortunately symptoms of iron deficiency are often confused with the effects of overtraining, such as muscle stiffness, a racing heart, and the feeling of exhaustion during and after exercise. Iron deficiency often goes undiagnosed until you are having a hard time putting one foot in front of the other, and even when tested for, a more sensitive test than what is commonly used may be needed for detection.
Iron deficiency is the most common deficiency for women from adolescence to menopause due to menstruation and pregnancy, affecting at least one in four women. Women need 15-18 mgs. of iron per day and the average American diet only has 8-10 mgs. Unfortunately many women are unaware they are iron-deficient as iron stores are often not checked during a routine exam, and when they are, iron stores (checked with a test called serum ferritin) need to be almost completely depleted before a lower red blood cell count (anemia) will develop, meaning those with a mild iron deficiency are missed. More than half the women in a study of 136 women between 18 and 55 with unexplained fatigue were shown to have low serum ferritin levels, confirming that many exhausted women are being misdiagnosed. Women put up with the fatigue and associated symptoms thinking they are just the normal result of our modern-day, fast-paced lifestyle.
It has been well known that women endurance athletes commonly develop iron deficiency and that this deficiency can impair performance, but only recently have we discovered that even mild degrees of iron deficiency affect the ability to exercise. We are also now finding that not only heavy-duty training can lead to a deficiency but moderate workouts as well. Research is also showing that those new to exercise can easily develop iron deficiency, which could explain why you are having a hard time sticking to your new program. If you are also trying to control or lose weight through a calorie-restricted diet, you may be lowering your dietary iron intake at a time when the demands for iron have risen.
Why are the demands for iron higher when you are exercising? Iron is lost through sweat and from bleeding of the digestive tract caused when the body experiences repetitive jarring, as in aerobic exercise. Blood vessels are also broken in the feet while running. When we lose blood we lose iron. For women who exercise regularly while pregnant, maintaining a healthy level of iron in the body is even more important. Women's iron requirements double during pregnancy to 30 mgs. and, without proper diet and effective supplementation, iron stores can drop and continue to decline with each subsequent pregnancy. A pregnant women needs adequate iron not only to give them the energy they need to exercise, but to prevent low birth weight and pre-term babies, as well as provide the iron stores for the baby's first six months of life.
Why does iron deficiency make it hard to get through your work out? Iron's job is to carry oxygen around the body, so if you are low in iron, you are low on oxygen. Iron deficiency also reduces the muscles' ability to utilize oxygen. The good news is that iron supplementation has been shown to help improve exercise endurance and performance. A recent research study took forty-one women between the ages of 18 and 33 with a mild iron deficiency and supplemented their diets with 16 mgs. of iron per day. The results were improved iron levels and exercise endurance in only 6 weeks. During another study, women receiving 10 mgs. of iron twice per day improved in muscle endurance by 15% and muscle strength by 26.5%, compared to no improvement with the control group over a six week period. And yet another study with iron-deficient women just beginning a fitness routine showed that they had a reduced ability to do aerobic exercise.
Adding iron-rich foods such as leafy green vegetables like spinach, kale, or even seaweed, which can be added to soup, can also help you get the iron you need. Other foods high in iron are raisins, prunes, apricots, lean meats, and eggs. However, it is important to recognize that, even though iron is such a vital nutrient, too much of a good thing is also not beneficial. Animal-based iron, found in flesh foods, has no feedback mechanism to shut off its absorption once your body has enough iron. It continues to absorb at a rate of 20% even when your iron stores are at or above normal levels, as opposed to plant-based iron which can shut down its absorption to 2-3% when your body already has enough iron. Because of this it is important when supplementing for prevention to only use a plant-based formula and to not exceed dosages above 30 mgs. Research is showing that iron deficiency can be corrected with lower, safer doses of iron than used previously. The results of a recent study at the Heidelberg Women's University Clinic using Floradix Iron & Herbs, a plant-based supplement, showed that it was effective at normalizing iron levels, with 90% of the participants able to take it without side affects. 70% of the women in the study reported improved symptoms versus 28% in the control group which increased their consumption of iron-rich foods alone.
Iron deficiency is not something women need to live with. It is preventable and treatable, and with a healthy diet and the use of a high-quality supplement, symptoms diminish, normal energy levels return, and endurance levels improve, helping to ensure an effective fitness program.
Dr. Cathy Carlson-Rink Naturopathic Physician and registered Midwife recommends most to her patients Floradix Iron and Herbs which is available in most health food stores. www.florahealth.com
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